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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoSTRUCTURAL
CHEMISTRY
ISSN: 2053-2296
Volume 61| Part 5| May 2005| Pages o276-o280
doi:10.1107/S0108270105007286

Supramolecular structures of four isomorphous anilinium 2-carb­­oxy-4-nitro­benzoate salts: 4-X-C6H4NH3+·C8H4NO6− (X = H, Cl, Br and I)

CROSSMARK_Color_square_no_text.svg
Christopher Glidewell,a* John N. Low,b Janet M. S. Skakleb and James L. Wardellc

aSchool of Chemistry, University of St Andrews, Fife KY16 9ST, Scotland, bDepartment of Chemistry, University of Aberdeen, Meston Walk, Old Aberdeen AB24 3UE, Scotland, and cInstituto de Química, Departamento de Química Inorgânica, Universidade Federal do Rio de Janeiro, 21945-970 Rio de Janeiro, RJ, Brazil
*Correspondence e-mail: cg@st-andrews.ac.uk

(Received 3 March 2005; accepted 7 March 2005; online 2 April 2005)

Anilinium 2-carb­oxy-4-nitro­benzoate, C6H8N+·C8H4NO6−, (I), 4-chloro­anilinium 2-carb­oxy-4-nitro­benzoate, C6H7ClN+·C8H4NO6−, (II), 4-bromo­anilinium 2-carb­oxy-4-nitro­benzoate, C6H7BrN+·C8H4NO6−, (III), and 4-iodo­anilinium 2-carb­oxy-4-nitro­benzoate, C6H7IN+·C8H4NO6−, (IV), are approximately isostructural. In each compound, the ions are linked into complex sheets by a combination of O—H⋯O and N—H⋯O hydrogen bonds. Within the sheets, two distinct one-dimensional substructures can be identified, viz. a chain of edge-fused R33(13) rings and a double helix of simple C22(9) chains. In (I)[link] and (IV)[link], the sheets are linked by a C—H⋯Onitro hydrogen bond and a two-centre C—I⋯Onitro inter­action, respectively, but the corresponding C—Cl⋯O and C—Br⋯O contact distances in (II)[link] and (III)[link] are not significantly shorter than the sum of the van der Waals radii.

Comment

We have recently reported the supramolecular structure of 4-iodo­anilinium 2-carboxy-6-nitrobenzoate (Glidewell et al., 2003[Glidewell, C., Low, J. N., Skakle, J. M. S. & Wardell, J. L. (2003). Acta Cryst. C59, o509-o511.]). We report here the structures of four closely related anilinium 2-carboxy-4-nitrobenzoate salts, 4-X-C6H4NH3+·C8H4NO6− [(I)[link] X = H, (II)[link] X = Cl, (III)[link] X = Br, and (IV)[link] X = I], where (IV)[link] differs from the previously reported compound in the location of the nitro group in the anion.

Compounds (I)–(IV)[link] all crystallize in space group C2/c, with unit cells of very similar size and shape; the only major differences between the unit-cell dimensions of (I)–(IV)[link] occur in the c dimension, which increases monotonically as the 4-substituent X changes from H, via Cl and Br, to I, with an overall change of nearly 7.4%. By contrast, the a and b dimensions show much smaller changes, and these are not monotonic in the same order as for c; thus, a shows its smallest value and b its largest value when X = Cl, i.e. compound (II)[link]. The β angle decreases monotonically from (I) to (IV)[link], and the unit-cell volumes increase likewise, with an overall increase from (I)[link] to (IV)[link] of nearly 9%.

[Scheme 1]

The title compounds (Figs. 1[link][link][link]–4[link]) are all salts, in which one carbox­yl group of the anion is fully ionized; the remaining carbox­yl H atom is fully ordered, as shown by the difference maps, and the C—O distances in the carbox­yl and carboxyl­ate units (Table 1[link]) are fully consistent with the H-atom locations deduced from the difference maps. While the nitro group and the un-ionized carbox­yl group show only modest displacements from the plane of the C1–C6 ar­yl ring, as shown by the relevant torsion angles (Table 5[link]), the carboxyl­ate group is almost orthogonal to the adjacent ar­yl ring, presumably for steric reasons. Consequently, there is no quinonoid-type bond fixation involving the nitro and carboxyl­ate substituents.

The hydrogen-bonded supramolecular structures of (I)–(IV)[link], which are determined primarily by a combination of O—H⋯O and N—H⋯O hydrogen bonds, reinforced by aromatic π–π stacking inter­actions, are all extremely similar and hence need be discussed in detail only for (I)[link]. The mol­ecular constitutions differ, of course, in respect of the nature of the 4-X substituent, but even here the supramolecular inter­actions are strikingly similar, with a C—H⋯Onitro hydrogen bond in (I)[link] closely echoed by two-centre X⋯Onitro contacts in (II)–(IV)[link] (Table 2[link]).

The two independent components in (I)[link] are linked into a single three-dimensional framework by a combination of O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonds (Tables 2[link] and 3[link]), reinforced by aromatic π–π stacking inter­actions. The formation of this framework is readily analysed in terms of its component one-dimensional substructures. The anions alone form chains running parallel to the [010] direction; carbox­yl atom O12 in the anion at (x, y, z) acts as a hydrogen-bond donor to carboxyl­ate atom O21 in the anion at ([{3\over 2}] − x, [{1\over 2}] + y, [{1\over 2}] − z), so forming a C(7) chain (Bernstein et al., 1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]) generated by the 21 screw axis along ([{3\over 4}], y, [{1\over 4}]) (Fig. 5[link]). In addition, atom N41 in the cation at (x, y, z) acts as a hydrogen-bond donor, via H41A and H41B, to carboxyl­ate atoms O22 at (x, y, z) and O21 at ([{3\over 2}] − x, −[{1\over 2}] + y, [{1\over 2}] − z), respectively, so enhancing the simple C(7) anion chain to form a chain of edge-fused R33(13) rings (Fig. 6[link]).

The third, and final, N—H⋯O hydrogen bond generates a second [010] motif; atom N41 at (x, y, z) acts as a hydrogen-bond donor, via H41C, to carbox­yl atom O11 in the anion at (1 − x, −1 + y, [{1\over 2}] − z), and atom N41 at (1 − x, −1 + y, [{1\over 2}] − z) in turn acts as a donor to atom O11 at (x, −2 + y, z), so forming a C22(9) chain running parallel to the [010] direction. Since the repeat period of this chain encompasses two unit cells, there must be two such chains to complete the structure; these two chains are related by the twofold rotation axis along ([{1\over 2}], y, [{1\over 4}]), so forming a double helix of C22(9) chains generated by the twofold rotation axis along ([{1\over 2}], y, [{1\over 4}]) (Fig. 7[link]). The combination of the two [010] motifs generated by the axes along ([{3\over 4}], y, [{1\over 4}]) and ([{1\over 2}], y, [{1\over 4}]), respectively, then generates a (001) sheet of some complexity. This sheet is reinforced by two independent π–π stacking inter­actions. The first of these inter­actions lies within the chain of R33(13) rings. The ar­yl rings of the cation at (x, y, z) and the anion at ([{3\over 2}] − x, −[{1\over 2}] + y, [{1\over 2}] − z) are nearly parallel, with a dihedral angle of only 3.4 (2)° between their planes; the inter­planar spacing is ca 3.46 Å and the ring-centroid separation is 3.705 (2) Å, corresponding to a ring offset of ca 1.33 Å. The second of these inter­actions lies within the double helix and involves the corresponding rings at (x, y, z) and (1 − x, y, [{1\over 2}] − z), with again a dihedral angle of only 3.4 (2)° between their planes; here the inter­planar spacing is ca 3.45 Å and the centroid separation is 3.752 (2) Å, giving a ring offset of ca 1.47 Å.

In each of (II)–(IV)[link], the formation of the hydrogen-bonded sheet and its two substructures is identical to that in (I)[link] (Tables 4[link][link]–6[link]). Two sheets of this type pass through each unit cell, in the domains 0 < z < 0.50 and 0.50 < z < 1; however, the inter­actions between adjacent sheets are not the same in the four structures (Table 2[link]). In (I)[link], atom C44 in the cation at (x, y, z) acts as a hydrogen-bond donor to nitro atom O51 in the anion at (x, 2 − y, −[{1\over 2}] + z), so producing a C22(15) chain running parallel to the [001] direction, generated by the c-glide plane at y = 1.0 (Fig. 8[link]), and linking the (001) sheets into a single framework. In a similar manner, in each of compounds (II)–(IV)[link], the halogen atoms X44 (X = Cl, Br and I) in the cation at (x, y, z) form a two-centre X⋯O contact with nitro atom O51 at (x, 2 − y, −[{1\over 2}] + z). The C—X⋯O units are all nearly linear (Table 2[link]) and the I⋯O distance in (IV)[link] is significantly shorter than the sum of the van der Waals radii (3.30 Å), taking into account the polar flattening of the I atom (Nyburg & Faerman, 1985[Nyburg, S. C. & Faerman, C. H. (1985). Acta Cryst. B41, 274-279.]). This iodo–nitro inter­action then generates a C22(15) chain (Starbuck et al., 1999[Starbuck, J., Norman, N. C. & Orpen, A. G. (1999). New J. Chem. 23, 969-972.]) along [001] (Fig. 9[link]). By contrast, the Cl⋯O and Br⋯O contact distances in (II)[link] and (III)[link] are not significantly shorter than the sum of the van der Waals radii (3.12 and 3.08 Å, respectively; Nyburg & Faerman, 1985[Nyburg, S. C. & Faerman, C. H. (1985). Acta Cryst. B41, 274-279.]), and so no structurally significant attractive inter­actions can be associated with these X⋯O contacts in (II)[link] and (III)[link].

It is of interest briefly to compare the structurally very similar series of salts (I)–(IV)[link] with the substituted anilinium salts (V)–(VII)[link] formed by 5-sulfosalicylic acid. These salts crystallize from aqueous ethanol as mono-, hemi- and monohydrates, respectively, in space groups P21 (Z = 2 and Z′ = 1), P21/c (Z = 8 and Z′ = 2) and Pbca (Z = 8 and Z′ = 1) (Smith et al., 2005[Smith, G., Wermuth, U. D. & White, J. M. (2005). Acta Cryst. C61, o105-o109.]). All three salts (V)–(VII)[link] form three-dimensional hydrogen-bonded structures in which the water mol­ecules play a key role. In (V)[link], the anions form chains generated by translation, whereas each of (VI)[link] and (VII)[link] contains the R22(8) dimer motif characteristic of simple carboxylic acids although absent from the structures of (I)–(IV)[link].

[Figure 1]
Figure 1
The independent components in (I)[link], showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2]
Figure 2
The independent components in (II)[link], showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 3]
Figure 3
The independent components in (III)[link], showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 4]
Figure 4
The independent components in (IV)[link], showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 5]
Figure 5
Part of the crystal structure of (I)[link], showing the formation of a hydrogen-bonded C(7) chain of anions along [010]. For clarity, H atoms bonded to C atoms have been omitted. Atoms marked with an asterisk (*), a hash (#) or a dollar sign ($) are at the symmetry positions (1 − x, [{1\over 2}] + y, [{3\over 2}] − z), (x, −1 + y, z) and (1 − x, −[{1\over 2}] + y, [{3\over 2}] − z), respectively.
[Figure 6]
Figure 6
A stereoview of part of the crystal structure of (I), showing the formation of a [010] chain of R33(13) rings. For clarity, H atoms bonded to C atoms have been omitted.
[Figure 7]
Figure 7
A stereoview of part of the crystal structure of (I)[link], showing the formation of a double helix of C22(9) chains along [010]. For clarity, H atoms bonded to C atoms have been omitted.
[Figure 8]
Figure 8
A stereoview of part of the crystal structure of (I)[link], showing the formation of a hydrogen-bonded C22(15) chain along [001]. For clarity, H atoms bonded to O or C atoms and not taking part in the motif shown have been omitted.
[Figure 9]
Figure 9
A stereoview of part of the crystal structure of (IV)[link], showing the formation of a C22(15) chain along [001] generated by the iodo–nitro inter­action. For clarity, H atoms bonded to C atoms have been omitted.

Experimental

A solution of 4-nitro­phthalic acid (0.42 g, 2 mmol) in hot ethanol (20 ml) was added to a solution of the appropriate aniline (2 mmol), also in ethanol (10 ml). The mixture was heated under reflux for 30 min and then allowed to cool to room temperature. The products, which precipitated after 24–48 h, were collected by filtration and recrystallized from methanol. Each product exhibited strong broad absorptions in the IR region 3000–2500 cm−1. Strong absorptions in the 1720–1490 cm−1 range were at 1716, 1610, 1529 and 1496 cm−1 for (I)[link]; 1716, 1612, 1536 and 1495 cm−1 for (II)[link]; 1698, 1610, 1529 and 1488 cm−1 for (III)[link]; and 1704, 1610, 1529 and 1489 cm−1 for (IV)[link].

Compound (I)[link]

Crystal data

  • C6H8N+·C8H4NO6−

  • Mr = 304.26

  • Monoclinic, C 2/c

  • a = 12.8131 (10) Å

  • b = 7.5521 (6) Å

  • c = 28.114 (2) Å

  • β = 98.13 (3)°

  • V = 2693.1 (4) Å3

  • Z = 8

  • Dx = 1.501 Mg m−3

  • Mo Kα radiation

  • Cell parameters from 2656

  • θ = 3.1–26.1°

  • μ = 0.12 mm−1

  • T = 120 (2) K

  • Plate, colourless

  • 0.14 × 0.10 × 0.02 mm
Data collection

  • Nonius KappaCCD diffractometer

  • φ and ω scans

  • Absorption correction: multi-scan(SADABS; Sheldrick, 2003[Sheldrick, G. M. (2003). SADABS. Version 2.10. University of Göttingen, Germany.])Tmin = 0.980, Tmax = 0.998

  • 13 132 measured reflections

  • 2656 independent reflections

  • 1474 reflections with I > 2σ(I)

  • Rint = 0.097

  • θmax = 26.1°

  • h = −15 → 15

  • k = −9 → 9

  • l = −33 → 34
Refinement

  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.077

  • wR(F2) = 0.210

  • S = 1.03

  • 2656 reflections

  • 200 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(Fo2) + (0.0871P)2 + 5.7738P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max = 0.001

  • Δρmax = 0.43 e Å−3

  • Δρmin = −0.30 e Å−3

Table 3
Hydrogen-bond geometry (Å, °) for (I)[link]

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O12—H12⋯O21i 1.00 1.48 2.476 (4) 176
N41—H41A⋯O22 0.91 1.89 2.799 (4) 173
N41—H41B⋯O21ii 0.91 1.92 2.828 (4) 172
N41—H41C⋯O11iii 0.91 2.02 2.884 (4) 158
Symmetry codes: (i) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iii) -x+1, [y-1, -z+{\script{1\over 2}}].

Compound (II)[link]

Crystal data

  • C6H7ClN+·C8H4NO6−

  • Mr = 338.70

  • Monoclinic, C 2/c

  • a = 12.7725 (16) Å

  • b = 7.5825 (7) Å

  • c = 29.595 (3) Å

  • β = 97.202 (5)°

  • V = 2843.6 (5) Å3

  • Z = 8

  • Dx = 1.582 Mg m−3

  • Mo Kα radiation

  • Cell parameters from 2342 reflections

  • θ = 3.1–25.0°

  • μ = 0.30 mm−1

  • T = 120 (2) K

  • Needle, colourless

  • 0.36 × 0.09 × 0.02 mm
Data collection

  • Nonius KappaCCD diffractometer

  • φ and ω scans

  • Absorption correction: multi-scan(SADABS; Sheldrick, 2003[Sheldrick, G. M. (2003). SADABS. Version 2.10. University of Göttingen, Germany.])Tmin = 0.910, Tmax = 0.994

  • 7613 measured reflections

  • 2342 independent reflections

  • 1887 reflections with I > 2σ(I)

  • Rint = 0.052

  • θmax = 25.0°

  • h = −14 → 14

  • k = −8 → 8

  • l = −34 → 35
Refinement

  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.072

  • wR(F2) = 0.190

  • S = 1.13

  • 2342 reflections

  • 208 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(Fo2) + (0.0614P)2 + 21.7547P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max < 0.001

  • Δρmax = 0.75 e Å−3

  • Δρmin = −0.40 e Å−3

Table 4
Hydrogen-bond geometry (Å, °) for (II)[link]

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O12—H12⋯O21i 0.92 1.58 2.484 (4) 169
N41—H41A⋯O22 0.83 1.99 2.806 (4) 166
N41—H41B⋯O21ii 0.84 1.97 2.804 (5) 173
N41—H41C⋯O11iii 0.84 2.07 2.888 (5) 166
Symmetry codes: (i) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iii) -x+1, [y-1, -z+{\script{1\over 2}}].

Compound (III)[link]

Crystal data

  • C6H7BrN+·C8H4NO6−

  • Mr = 383.16

  • Monoclinic, C 2/c

  • a = 12.8292 (6) Å

  • b = 7.5750 (3) Å

  • c = 29.8202 (13) Å

  • β = 97.0270 (11)°

  • V = 2876.2 (2) Å3

  • Z = 8

  • Dx = 1.770 Mg m−3

  • Mo Kα radiation

  • Cell parameters from 3305 reflections

  • θ = 3.1–27.6°

  • μ = 2.89 mm−1

  • T = 120 (2) K

  • Plate, yellow

  • 0.26 × 0.04 × 0.02 mm
Data collection

  • Nonius KappaCCD diffractometer

  • φ and ω scans

  • Absorption correction: multi-scan(SADABS; Sheldrick, 2003[Sheldrick, G. M. (2003). SADABS. Version 2.10. University of Göttingen, Germany.])Tmin = 0.520, Tmax = 0.944

  • 16 011 measured reflections

  • 3305 independent reflections

  • 2941 reflections with I > 2σ(I)

  • Rint = 0.041

  • θmax = 27.6°

  • h = −16 → 16

  • k = −9 → 9

  • l = −38 → 38
Refinement

  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.114

  • S = 1.08

  • 3304 reflections

  • 208 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(Fo2) + (0.0524P)2 + 13.8988P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max < 0.001

  • Δρmax = 2.36 e Å−3

  • Δρmin = −0.76 e Å−3

Table 5
Hydrogen-bond geometry (Å, °) for (III)[link]

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O12—H12⋯O21i 0.92 1.57 2.481 (3) 169
N41—H41A⋯O22 0.84 1.98 2.806 (3) 166
N41—H41B⋯O21ii 0.84 1.97 2.811 (3) 173
N41—H41C⋯O11iii 0.84 2.06 2.888 (3) 167
Symmetry codes: (i) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iii) -x+1, [y-1, -z+{\script{1\over 2}}].

Compound (IV)[link]

Crystal data

  • C6H7IN+·C8H4NO6−

  • Mr = 430.15

  • Monoclinic, C 2/c

  • a = 12.9459 (3) Å

  • b = 7.5576 (1) Å

  • c = 30.1790 (6) Å

  • β = 96.784 (1)°

  • V = 2932.04 (10) Å3

  • Z = 8

  • Dx = 1.949 Mg m−3

  • Mo Kα radiation

  • Cell parameters from 3354 reflections

  • θ = 3.1–27.5°

  • μ = 2.22 mm−1

  • T = 120 (2) K

  • Plate, colourless

  • 0.40 × 0.10 × 0.02 mm
Data collection

  • Nonius KappaCCD diffractometer

  • φ and ω scans

  • Absorption correction: multi-scan(SADABS; Sheldrick, 2003[Sheldrick, G. M. (2003). SADABS. Version 2.10. University of Göttingen, Germany.])Tmin = 0.471, Tmax = 0.957

  • 16 634 measured reflections

  • 3354 independent reflections

  • 2941 reflections with I > 2σ(I)

  • Rint = 0.051

  • θmax = 27.5°

  • h = −16 → 16

  • k = −9 → 9

  • l = −39 → 39
Refinement

  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.039

  • wR(F2) = 0.160

  • S = 1.13

  • 3354 reflections

  • 210 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(Fo2) + (0.104P)2 + 15.6247P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max < 0.001

  • Δρmax = 2.65 e Å−3

  • Δρmin = −1.79 e Å−3

Table 6
Hydrogen-bond geometry (Å, °) for (IV)[link]

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O12—H12⋯O21i 0.84 1.69 2.479 (5) 156
N41—H41A⋯O22 0.91 1.91 2.812 (5) 173
N41—H41B⋯O21ii 0.91 1.92 2.826 (5) 174
N41—H41C⋯O11iii 0.91 2.03 2.896 (5) 159
Symmetry codes: (i) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iii) -x+1, y-1, [-z+{\script{1\over 2}}].

Table 1
Selected geometric parameters (Å, °) for compounds (I)–(IV)

  (I) (II) (III) (IV)
C11—O11 1.211 (5) 1.210 (5) 1.220 (4) 1.277 (6)
C11—O12 1.308 (5) 1.306 (5) 1.310 (3) 1.302 (6)
C21—O21 1.283 (4) 1.280 (5) 1.286 (3) 1.289 (6)
C21—O22 1.277 (5) 1.231 (5) 1.236 (3) 1.235 (6)
         
C2—C1—C11—O11 163.1 (4) 162.1 (5) 162.4 (3) 161.0 (5)
C1—C2—C21—O21 101.1 (4) 99.4 (5) 100.2 (3) 100.0 (5)
C4—C5—N51—O51 173.5 (4) −176.4 (5) −175.1 (3) −172.9 (5)

Table 2
Short intermolecular C44—X44⋯O51iv contacts (Å, °) for compounds (I)–(IV)

Compound C—X X⋯Oiv C⋯Oiv C—X⋯Oiv X⋯Oiv—Niv
(I) (X = H) 0.95 2.55 3.477 (6) 167 103
(II) (X = Cl) 1.751 (5) 3.109 (4) 4.849 (6) 171.8 (2) 111.0 (3)
(III) (X = Br) 1.904 (3) 3.108 (3) 5.001 (4) 172.0 (2) 111.2 (2)
(IV) (X = I) 2.115 (5) 3.168 (4) 5.270 (4) 171.8 (2) 110.9 (3)
Symmetry code: (iv) [x, 2-y, -{1 \over 2}+z].

For each of (I)–(IV), the systematic absences permitted C2/c and Cc as possible space groups; C2/c was selected in each case and confirmed by the subsequent analyses. All H atoms were located from difference maps. H atoms bonded to C atoms were then treated as riding atoms, with C—H distances of 0.95 Å and Uiso(H) values of 1.2Ueq(C). H atoms bonded to N or O atoms were allowed to ride at the distances deduced from the difference maps and with Uiso(H) = 1.2Ueq(N) or 1.5Ueq(O); the resulting N—H distances were 0.83–0.91 Å and the O—H distances were 0.84–0.92 Å. For (III)[link], the highest difference peak was located 0.88 Å from atom Br44, while the deepest hole was located 0.64 Å from Br44.

For all compounds, data collection: COLLECT (Hooft, 1999[Hooft, R. W. W. (1999). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]) and COLLECT; data reduction: DENZO and COLLECT; structure solution: OSCAIL (McArdle, 2003[McArdle, P. (2003). OSCAIL for Windows. Version 10. Crystallography Centre, Chemistry Department, NUI Galway, Ireland.]) and SHELXS97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); structure refinement: OSCAIL and SHELXL97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); mol­ecular graphics: PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]); software used to prepare material for publication: SHELXL97 and PRPKAPPA (Ferguson, 1999[Ferguson, G. (1999). PRPKAPPA. University of Guelph, Canada.]).

Supporting information

Crystal structure: contains datablocks global, I, II, III, IV. DOI: 10.1107/S0108270105007286/sk1823sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S0108270105007286/sk1823Isup2.hkl

Structure factors: contains datablock II. DOI: 10.1107/S0108270105007286/sk1823IIsup3.hkl

Structure factors: contains datablock III. DOI: 10.1107/S0108270105007286/sk1823IIIsup4.hkl

Structure factors: contains datablock IV. DOI: 10.1107/S0108270105007286/sk1823IVsup5.hkl


Comment top

We have recently reported the supramolecular structure of 4-iodoanilinium 3-nitro-(hydrogenphthalate) (Glidewell et al., 2003). We report here the structures of four closely related anilinium 5-nitro-(hydrogenphthalate) salts [4-XC6H4NH3]+·[C8H4NO6]− [(I) X = H; (II) X = Cl; (III) X = Br; and (IV) X = I], where (IV) differs from the previously reported compound in the location of the nitro group in the anion

Compounds (I)–(IV) all crystallize in space group C2/c, with unit cells of very similar size and shape: the only major differences between the unit-cell dimensions of (I)–(IV) occur in the c dimension, which increases monotonically as the 4-substituent X changes from H, via Cl and Br, to I, with an overall change of nearly 7.4%. By contrast, the dimensions a and b show much smaller changes, and these are not monotonic in the same order as for c: thus a shows its smallest value and b its largest value when X = Cl, i.e. compound (II). The β angle decreases monotonically from (I)–(IV), and the unit-cell volumes increase likewise, with an overall increase from (I) to (IV) of nearly 9%.

The compounds (Figs. 1–4) are all salts, in which one carboxyl group of the anion is fully ionized; the remaining carboxyl H atom is fully ordered, as shown by the difference maps, and the C—O distances in the carboxyl and carboxylate units (Table 1) are fully consistent with the H-atom locations deduced from the difference maps. While the nitro group and the un-ionized carboxyl group show only modest displacements from the plane of the aryl ring C1–C6, as shown by the relevant torsion angles (Table 1), the carboxylate group is almost orthogonal to the adjacent aryl ring, presumably for steric reasons. Consequently, there is no quinonoid-type bond fixation involving the nitro and carboxylate substituents.

The hydrogen-bonded supramolecular structures of (I)–(IV), which are determined primarily by a combination of O—H···O and N—H···O hydrogen bonds, reinforced by aromatic π–π stacking interactions, are all extremely similar, and hence need be discussed in detail only for (I). The molecular constitutions differ, of course, in respect of the nature of the 4-X substituent, but even here, the supramolecular interactions are strikingly similar, with a C—H···O(nitro) hydrogen bond in compound (I) closely echoed by two-centre X···O(nitro) contacts in compounds (II)–(IV) (Table 2).

The two independent components in compound (I) are linked into a single three-dimensional framework by a combination of O—H···O, N—H···O and C—H···O hydrogen bonds (Table 3), reinforced by aromatic π–π stacking interactions. The formation of this framework is readily analysed in terms of its component one-dimensional substructures. The anions alone form chains running parallel to the [010] direction; carboxyl atom O12 in the anion at (x, y, z) acts as a hydrogen-bond donor to carboxylate atom O21 in the anion at (3/2 − x, 1/2 + y, 1/2 − z), so forming a C(7) chain (Bernstein et al., 1995) generated by the 21 screw axis along (3/4, y, 1/4) (Fig. 5). In addition, atom N41 in the cation at (x, y, z) acts as a hydrogen-bond donor, via H41A and H41B, respectively, to carboxylate atoms O22 at (x, y, z) and O21 at (3/2 − x, −1/2 + y, 1/2 − z), so enhancing the simple C(7) anion chain to form a chain of edge-fused R33(13) rings (Fig. 6).

The third, and final, N—H···O hydrogen bond generates a second [010] motif; atom N41 at (x, y, z) acts as a hydrogen-bond donor, via H41C, to carboxyl atom O11 in the anion at (1 − x, −1 + y, 1/2 − z), and atom N41 at (1 − x, −1 + y, 1/2 − z) in turn acts as a donor to atom O11 at (x, −2 + y, z), so forming a C22(9) chain running parallel to the [010] direction. Since the repeat period of this chain encompasses two unit cells, there must be two such chains to complete the structure; these two chains are related by the twofold rotation axis along (1/2, y, 1/4), so forming a double helix of C22(9) chains generated by the twofold rotation axis along (1/2, y, 1/4) (Fig. 7). The combination of the two [010] motifs generated by the axes along (3/4, y, 1/4) and (1/2, y, 1/4), respectively, then generates a (001) sheet of some complexity. This sheet is reinforced by two independent π–π stacking interactions. The first of these interactions lies within the chain of R33(13) rings. The aryl rings of the cation at (x, y, z) and the anion at (3/2 − x, −1/2 + y, 1/2 − z) are nearly parallel, with a dihedral angle of only 3.4 (2)° between their planes; the interplanar spacing is ca 3.46 Å and the ring-centroid separation is 3.705 (2) Å, corresponding to a ring offset of ca 1.33 Å. The second of these interactions lies within the double helix, and involves the corresponding rings at (x, y, z) and (1 − x, y, 1/2 − z), with again a dihedral angle of only 3.4 (2)° between their planes; here the interplanar spacing is ca 3.45 Å and the centroid separation is 3.752 (2) Å, giving a ring offset of ca 1.47 Å.

In each of (II)–(IV), the formation of the hydrogen-bonded sheet and its two substructures is identical to that in (I) (Tables 3–6). Two sheets of this type pass through each unit cell, in the domains 0 < z < 0.50 and 0.50 < z < 1; however, the interactions between adjacent sheets are not the same in the four structures (Table 2). In (I), atom C44 in the cation at (x, y, z) acts as a hydrogen-bond donor to nitro atom O51 in the anion at (x, 2 − y, −1/2 + z), so producing a C22(15) chain running parallel to the [001] direction, generated by the c-glide plane at y = 1.0 (Fig. 8), and linking the (001) sheets into a single framework. In a similar manner, in each of compounds (II)–(IV), the halogen atoms X44 (X = Cl, Br and I) in the cation at (x, y, z) form a two-centre X···O contact with nitro atom O51 at (x, 2 − y, −1/2 + z). The C—X···O units are all nearly linear (Table 2), and the I···O distance in (IV) is significantly shorter than the sum of van der Waals radii (3.30 Å), taking into account the polar flattening of the I atom (Nyburg & Faerman, 1985). This iodo–nitro interaction then generates a C22(15) chain (Starbuck et al., 1999) along [001] (Fig. 9). By contrast, the Cl···O and Br···O contact distances in (II) and (III) are not significantly shorter than the sum of van der Waals radii (3.12 Å and 3.08 Å, respectively; Nyburg & Faerman, 1985), and so no structurally significant attractive interactions can be associated with these X···O contacts in (II) and (III).

It is of interest briefly to compare the structurally very similar series of salts (I)–(IV) with the substituted anilinium salts (V)–(VII) formed by 5-sulfosalicylic acid. These salts crystallize from aqueous ethanol as mono-, hemi- and monohydrates respectively, in space groups P21 (Z = 2 and Z' = 1), P21/c (Z = 8 and Z' = 2) and Pbca (Z = 8 and Z' = 1) (Smith et al., 2005). All three salts (V)–(VII) form three-dimensional hydrogen-bonded structures in which the water molecules play a key role. In (V), the anions form chains generated by translation, whereas each of (VI) and (VII) contains the R22(8) dimer motif characteristic of simple carboxylic acids, although absent from the structures of (I)–(IV).

Experimental top

A solution of 4-nitrophthalic acid (0.42 g, 2 mmol) in hot ethanol (20 ml) was added to a solution of the appropriate aniline (2 mmol), also in ethanol (10 ml) The mixture was heated under reflux for 30 min and then allowed to cool to room temperature. The products which precipitated after 24–48 h were collected by filtration and recrystallized from methanol. Each product exhibited strong broad absorptions in the IR region, from 3000–2500 cm−1. Strong absorptions in the 1720–1490 cm−1 range were at 1716, 1610, 1529 and 1496 cm−1 for (I); 1716, 1612, 1536 and 1495 cm−1 for (II); 1698, 1610, 1529 and 1488 cm−1 for (III); and 1704, 1610, 1529 and 1489 cm−1 for (IV).

Refinement top

For each of (I)–(IV), the systematic absences permitted C2/c and Cc as possible space groups; C2/c was selected in each case and confirmed by the subsequent analyses. All H atoms were located from difference maps. H atoms bonded to C atoms were then treated as riding atoms, with C—H distances of 0.95 Å and Uiso(H) values of 1.2Ueq(C). H atoms bonded to N or O atoms were allowed to ride at the distances deduced from the difference maps and with Uiso(H) = 1.2Ueq(N) or 1.5Ueq(O); the resulting N—H distances were 0.83–0.91 Å and the O—H distances were 0.84–0.92 Å. For compound (III), the highest difference peak was located 0.88 Å from Br44, while the deepest hole was located 0.64 Å from Br44.

Computing details top

For all compounds, data collection: COLLECT (Hooft, 1999); cell refinement: DENZO (Otwinowski & Minor, 1997) and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: OSCAIL (McArdle, 2003) and SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: OSCAIL and SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 and PRPKAPPA (Ferguson, 1999).

Figures top
[Figure 1] Fig. 1. The independent components in (I), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. The independent components in (II), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 3] Fig. 3. The independent components in (III), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 4] Fig. 4. The independent components in (IV), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 5] Fig. 5. Part of the crystal structure of (I), showing the formation of a hydrogen-bonded C(7) chain of anions along [010]. For clarity, H atoms bonded to C atoms have been omitted. Atoms marked with an asterisk (*), a hash (#) or a dollar sign ($) are at the symmetry positions (1 − x, 1/2 + y, 3/2 − z), (x, −1 + y, z) and (1 − x, −1/2 + y, 3/2 − z), respectively.
[Figure 6] Fig. 6. Part of the crystal structure of (I), showing the formation of a [010] chain of R33(13) rings. For clarity, H atoms bonded to C atoms have been omitted. Atoms marked with an asterisk (*), a hash (#) or a dollar sign ($) are at the symmetry positions (3/2 − x, 1/2 + y, 1/2 − z), (x, −1 + y, z) and (3/2 − x, −1/2 + y, 1/2 − z), respectively.
[Figure 7] Fig. 7. A stereoview of part of the crystal structure of (I), showing the formation of a double helix of C22(9) chains along [010]. For clarity, H atoms bonded to C atoms have been omitted.
[Figure 8] Fig. 8. A stereoview of part of the crystal structure of (I), showing the formation of a hydrogen-bonded C22(15) chain along [001]. For clarity, H atoms bonded to O or C atoms, and not taking part in the motif shown, have been omitted.
[Figure 9] Fig. 9. A stereoview of part of the crystal structure of (IV), showing the formation of a C22(15) chain along [001] generated by the iodo–nitro interaction.
(I) Anilinium 2-carboxy-4-nitrobenzoate top
Crystal data top
C6H8N+·C8H4NO6−F(000) = 1264
Mr = 304.26Dx = 1.501 Mg m−3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 26892 reflections
a = 12.8131 (10) Åθ = 3.1–26.1°
b = 7.5521 (6) ŵ = 0.12 mm−1
c = 28.114 (2) ÅT = 120 K
β = 98.13 (3)°Plate, colourless
V = 2693.1 (4) Å30.14 × 0.10 × 0.02 mm
Z = 8
Data collection top
Nonius KappaCCD
diffractometer		2656 independent reflections
Radiation source: Bruker–Nonius FR591 rotating anode1474 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.097
Detector resolution: 9.091 pixels mm-1θmax = 26.1°, θmin = 3.1°
ϕ and ω scansh = −15→15
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		k = −9→9
Tmin = 0.980, Tmax = 0.998l = −33→34
13132 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.077Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.210H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0871P)2 + 5.7738P]
where P = (Fo2 + 2Fc2)/3
2656 reflections(Δ/σ)max = 0.001
200 parametersΔρmax = 0.43 e Å−3
0 restraintsΔρmin = −0.30 e Å−3
Crystal data top
C6H8N+·C8H4NO6−V = 2693.1 (4) Å3
Mr = 304.26Z = 8
Monoclinic, C2/cMo Kα radiation
a = 12.8131 (10) ŵ = 0.12 mm−1
b = 7.5521 (6) ÅT = 120 K
c = 28.114 (2) Å0.14 × 0.10 × 0.02 mm
β = 98.13 (3)°
Data collection top
Nonius KappaCCD
diffractometer		2656 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		1474 reflections with I > 2σ(I)
Tmin = 0.980, Tmax = 0.998Rint = 0.097
13132 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0770 restraints
wR(F2) = 0.210H-atom parameters constrained
S = 1.03Δρmax = 0.43 e Å−3
2656 reflectionsΔρmin = −0.30 e Å−3
200 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O110.6067 (2)1.1176 (4)0.28978 (10)0.0396 (8)
O120.6964 (2)0.8853 (4)0.26773 (10)0.0334 (7)
O210.78397 (19)0.5446 (3)0.30747 (9)0.0305 (7)
O220.6094 (2)0.5228 (4)0.28500 (10)0.0329 (7)
O510.6220 (3)1.1806 (5)0.46471 (12)0.0624 (10)
O520.6227 (3)0.9472 (5)0.50986 (12)0.0602 (10)
N410.5756 (2)0.3294 (4)0.19925 (11)0.0301 (8)
N510.6279 (3)1.0183 (6)0.47091 (15)0.0472 (10)
C10.6503 (3)0.8831 (5)0.34551 (14)0.0280 (9)
C20.6713 (3)0.7025 (5)0.35178 (14)0.0275 (9)
C30.6751 (3)0.6271 (6)0.39751 (15)0.0322 (10)
C40.6588 (3)0.7303 (6)0.43643 (16)0.0376 (11)
C50.6413 (3)0.9091 (6)0.42916 (15)0.0333 (10)
C60.6361 (3)0.9866 (6)0.38494 (15)0.0302 (10)
C110.6472 (3)0.9738 (5)0.29785 (15)0.0299 (10)
C210.6873 (3)0.5812 (5)0.31052 (15)0.0293 (10)
C410.5828 (3)0.4371 (5)0.15697 (15)0.0295 (10)
C420.5724 (3)0.3551 (6)0.11266 (15)0.0355 (11)
C430.5815 (3)0.4571 (6)0.07225 (15)0.0380 (11)
C440.6011 (3)0.6363 (6)0.07642 (17)0.0404 (11)
C450.6118 (3)0.7149 (6)0.12095 (16)0.0368 (11)
C460.6020 (3)0.6152 (6)0.16155 (16)0.0326 (10)
H30.68910.50420.40180.039*
H40.65960.67930.46740.045*
H60.62291.10990.38120.036*
H120.70220.94580.23660.050*
H41A0.59110.39700.22610.045*
H41B0.62220.23800.20030.045*
H41C0.50900.28580.19780.045*
H420.55920.23140.10980.043*
H430.57410.40280.04150.046*
H440.60720.70510.04870.048*
H450.62600.83820.12390.044*
H460.60850.67000.19220.039*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O110.0354 (16)0.0396 (18)0.046 (2)0.0092 (14)0.0139 (14)0.0019 (15)
O120.0345 (15)0.0368 (16)0.0310 (17)0.0025 (13)0.0114 (13)−0.0009 (13)
O210.0246 (14)0.0344 (16)0.0339 (17)0.0009 (12)0.0086 (12)−0.0028 (13)
O220.0245 (14)0.0398 (17)0.0343 (17)−0.0047 (12)0.0036 (13)−0.0048 (14)
O510.085 (3)0.050 (2)0.051 (2)0.0206 (19)0.0033 (19)−0.0100 (18)
O520.073 (2)0.085 (3)0.0235 (19)0.021 (2)0.0093 (17)−0.0006 (19)
N410.0242 (17)0.0319 (19)0.035 (2)−0.0013 (14)0.0074 (15)−0.0019 (16)
N510.046 (2)0.059 (3)0.036 (3)0.017 (2)0.0032 (19)−0.008 (2)
C10.024 (2)0.035 (2)0.027 (2)−0.0009 (17)0.0080 (17)−0.0003 (19)
C20.0196 (19)0.034 (2)0.030 (2)−0.0012 (17)0.0070 (17)−0.0023 (19)
C30.030 (2)0.037 (2)0.031 (3)0.0002 (18)0.0093 (19)0.003 (2)
C40.031 (2)0.047 (3)0.036 (3)−0.002 (2)0.008 (2)0.002 (2)
C50.026 (2)0.047 (3)0.028 (2)0.0042 (19)0.0079 (18)−0.010 (2)
C60.019 (2)0.038 (2)0.035 (3)0.0030 (17)0.0073 (18)−0.003 (2)
C110.0198 (19)0.032 (2)0.039 (3)0.0000 (18)0.0061 (18)−0.003 (2)
C210.028 (2)0.029 (2)0.033 (2)0.0016 (18)0.011 (2)0.0067 (19)
C410.0172 (19)0.040 (3)0.032 (3)−0.0008 (17)0.0066 (18)0.004 (2)
C420.030 (2)0.041 (3)0.038 (3)−0.0027 (19)0.010 (2)0.000 (2)
C430.029 (2)0.060 (3)0.025 (2)0.000 (2)0.0076 (19)−0.004 (2)
C440.033 (2)0.049 (3)0.040 (3)0.000 (2)0.009 (2)0.008 (2)
C450.028 (2)0.040 (3)0.043 (3)0.0009 (19)0.007 (2)0.008 (2)
C460.026 (2)0.037 (2)0.035 (3)0.0008 (18)0.0075 (19)0.000 (2)
Geometric parameters (Å, º) top
C1—C61.389 (5)N51—O511.239 (5)
C1—C21.396 (6)C6—H60.95
C1—C111.500 (6)C41—C461.371 (6)
C11—O111.211 (5)C41—C421.381 (6)
C11—O121.308 (5)C41—N411.454 (5)
O12—H121.00N41—H41A0.91
C2—C31.401 (5)N41—H41B0.91
C2—C211.515 (6)N41—H41C0.91
C21—O221.227 (5)C42—C431.391 (6)
C21—O211.283 (4)C42—H420.95
C3—C41.383 (6)C43—C441.378 (6)
C3—H30.95C43—H430.95
C4—C51.379 (6)C44—C451.375 (6)
C4—H40.95C44—H440.95
C5—C61.367 (6)C45—C461.388 (6)
C5—N511.465 (5)C45—H450.95
N51—O521.230 (5)C46—H460.95
C6—C1—C2119.6 (4)C5—C6—H6120.3
C6—C1—C11117.8 (4)C1—C6—H6120.3
C2—C1—C11122.6 (4)C46—C41—C42121.2 (4)
O11—C11—O12124.7 (4)C46—C41—N41120.2 (4)
O11—C11—C1122.2 (4)C42—C41—N41118.5 (4)
O12—C11—C1113.0 (3)C41—N41—H41A109.5
C11—O12—H12115.9C41—N41—H41B109.5
C1—C2—C3119.6 (4)H41A—N41—H41B109.5
C1—C2—C21122.6 (4)C41—N41—H41C109.5
C3—C2—C21117.8 (3)H41A—N41—H41C109.5
O22—C21—O21126.7 (4)H41B—N41—H41C109.5
O22—C21—C2118.5 (3)C41—C42—C43118.7 (4)
O21—C21—C2114.7 (3)C41—C42—H42120.7
C4—C3—C2120.5 (4)C43—C42—H42120.7
C4—C3—H3119.8C44—C43—C42120.7 (4)
C2—C3—H3119.8C44—C43—H43119.7
C5—C4—C3118.3 (4)C42—C43—H43119.7
C5—C4—H4120.9C45—C44—C43119.7 (4)
C3—C4—H4120.9C45—C44—H44120.2
C6—C5—C4122.7 (4)C43—C44—H44120.2
C6—C5—N51119.4 (4)C44—C45—C46120.4 (4)
C4—C5—N51117.9 (4)C44—C45—H45119.8
O52—N51—O51123.2 (4)C46—C45—H45119.8
O52—N51—C5119.7 (4)C41—C46—C45119.4 (4)
O51—N51—C5117.1 (4)C41—C46—H46120.3
C5—C6—C1119.3 (4)C45—C46—H46120.3
C6—C1—C11—O11−19.8 (5)C6—C5—N51—O52173.3 (4)
C2—C1—C11—O11163.1 (4)C4—C5—N51—O52−6.7 (6)
C6—C1—C11—O12157.3 (3)C6—C5—N51—O51−6.5 (6)
C2—C1—C11—O12−19.8 (5)C4—C5—N51—O51173.5 (4)
C6—C1—C2—C31.6 (5)C4—C5—C6—C1−0.9 (6)
C11—C1—C2—C3178.6 (3)N51—C5—C6—C1179.1 (3)
C6—C1—C2—C21179.8 (3)C2—C1—C6—C5−1.0 (6)
C11—C1—C2—C21−3.1 (6)C11—C1—C6—C5−178.2 (3)
C1—C2—C21—O22−81.7 (5)C46—C41—C42—C43−0.2 (6)
C3—C2—C21—O2296.5 (4)N41—C41—C42—C43−178.6 (3)
C1—C2—C21—O21101.1 (4)C41—C42—C43—C440.4 (6)
C3—C2—C21—O21−80.7 (4)C42—C43—C44—C450.0 (6)
C1—C2—C3—C4−0.3 (6)C43—C44—C45—C46−0.6 (6)
C21—C2—C3—C4−178.6 (3)C42—C41—C46—C45−0.4 (6)
C2—C3—C4—C5−1.6 (6)N41—C41—C46—C45178.0 (3)
C3—C4—C5—C62.2 (6)C44—C45—C46—C410.8 (6)
C3—C4—C5—N51−177.8 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O12—H12···O21i1.001.482.476 (4)176
N41—H41A···O220.911.892.799 (4)173
N41—H41B···O21ii0.911.922.828 (4)172
N41—H41C···O11iii0.912.022.884 (4)158
C44—H44···O51iv0.952.553.477 (6)167
Symmetry codes: (i) −x+3/2, y+1/2, −z+1/2; (ii) −x+3/2, y−1/2, −z+1/2; (iii) −x+1, y−1, −z+1/2; (iv) x, −y+2, z−1/2.
(II) 4-Chloroanilinium 2-carboxy-4-nitrobenzoate top
Crystal data top
C6H7ClN+·C8H4NO6−F(000) = 1392
Mr = 338.70Dx = 1.582 Mg m−3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 2342 reflections
a = 12.7725 (16) Åθ = 3.1–25.0°
b = 7.5825 (7) ŵ = 0.30 mm−1
c = 29.595 (3) ÅT = 120 K
β = 97.202 (5)°Needle, colourless
V = 2843.6 (5) Å30.36 × 0.09 × 0.02 mm
Z = 8
Data collection top
Nonius KappaCCD
diffractometer		2342 independent reflections
Radiation source: Bruker-Nonius FR91 rotating anode1887 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.052
Detector resolution: 9.091 pixels mm-1θmax = 25.0°, θmin = 3.1°
ϕ and ω scansh = −14→14
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		k = −8→8
Tmin = 0.910, Tmax = 0.994l = −34→35
7613 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.072Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.190H-atom parameters constrained
S = 1.13 w = 1/[σ2(Fo2) + (0.0614P)2 + 21.7547P]
where P = (Fo2 + 2Fc2)/3
2342 reflections(Δ/σ)max < 0.001
208 parametersΔρmax = 0.75 e Å−3
0 restraintsΔρmin = −0.40 e Å−3
Crystal data top
C6H7ClN+·C8H4NO6−V = 2843.6 (5) Å3
Mr = 338.70Z = 8
Monoclinic, C2/cMo Kα radiation
a = 12.7725 (16) ŵ = 0.30 mm−1
b = 7.5825 (7) ÅT = 120 K
c = 29.595 (3) Å0.36 × 0.09 × 0.02 mm
β = 97.202 (5)°
Data collection top
Nonius KappaCCD
diffractometer		2342 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		1887 reflections with I > 2σ(I)
Tmin = 0.910, Tmax = 0.994Rint = 0.052
7613 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0720 restraints
wR(F2) = 0.190H-atom parameters constrained
S = 1.13 w = 1/[σ2(Fo2) + (0.0614P)2 + 21.7547P]
where P = (Fo2 + 2Fc2)/3
2342 reflectionsΔρmax = 0.75 e Å−3
208 parametersΔρmin = −0.40 e Å−3
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl440.61546 (12)0.68804 (18)0.04099 (4)0.0391 (4)
O110.6049 (3)1.0273 (4)0.28725 (11)0.0279 (8)
O120.6949 (3)0.7956 (4)0.26645 (10)0.0225 (8)
O210.7832 (2)0.4576 (4)0.30470 (10)0.0204 (7)
O220.6085 (3)0.4339 (4)0.28400 (10)0.0234 (8)
O510.6030 (3)1.0940 (5)0.45151 (12)0.0450 (11)
O520.6394 (3)0.8740 (5)0.49757 (11)0.0405 (10)
N410.5783 (3)0.2400 (5)0.20265 (11)0.0195 (8)
N510.6257 (3)0.9394 (6)0.45953 (13)0.0291 (10)
C10.6481 (4)0.7952 (6)0.34041 (14)0.0184 (10)
C20.6682 (4)0.6139 (6)0.34701 (15)0.0199 (10)
C30.6721 (4)0.5426 (6)0.39027 (15)0.0241 (10)
C40.6576 (4)0.6463 (6)0.42737 (15)0.0245 (11)
C50.6378 (4)0.8240 (6)0.42008 (15)0.0237 (11)
C60.6334 (4)0.9002 (6)0.37762 (15)0.0229 (10)
C110.6457 (4)0.8847 (6)0.29513 (15)0.0203 (10)
C210.6864 (4)0.4924 (6)0.30806 (14)0.0184 (10)
C410.5860 (4)0.3518 (6)0.16311 (15)0.0198 (10)
C420.5761 (4)0.2752 (6)0.12067 (15)0.0225 (10)
C430.5836 (4)0.3782 (6)0.08268 (15)0.0246 (11)
C440.6039 (4)0.5563 (7)0.08869 (16)0.0276 (11)
C450.6148 (4)0.6341 (6)0.13114 (15)0.0250 (11)
C460.6048 (4)0.5303 (6)0.16881 (15)0.0221 (10)
H30.68490.42000.39450.029*
H40.66120.59700.45700.029*
H60.62051.02300.37380.027*
H120.69630.84810.23860.034*
H41A0.59730.28940.22750.023*
H41B0.62310.15920.20230.023*
H41C0.51940.19250.20330.023*
H420.56420.15190.11750.027*
H430.57490.32770.05310.030*
H450.62900.75670.13450.030*
H460.61080.58140.19830.027*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl440.0452 (9)0.0429 (8)0.0292 (7)−0.0041 (6)0.0048 (6)0.0149 (6)
O110.031 (2)0.0230 (18)0.0303 (18)0.0099 (15)0.0079 (15)0.0043 (14)
O120.029 (2)0.0197 (16)0.0197 (15)0.0030 (14)0.0082 (14)0.0013 (12)
O210.0236 (19)0.0166 (16)0.0213 (15)0.0014 (13)0.0036 (14)0.0003 (12)
O220.0241 (19)0.0225 (17)0.0223 (16)−0.0033 (14)−0.0013 (15)−0.0045 (13)
O510.066 (3)0.036 (2)0.032 (2)0.018 (2)0.0029 (19)−0.0086 (17)
O520.058 (3)0.045 (2)0.0186 (18)−0.0001 (19)0.0042 (17)−0.0026 (16)
N410.017 (2)0.0226 (19)0.0195 (18)0.0002 (16)0.0043 (15)−0.0006 (15)
N510.032 (3)0.035 (2)0.021 (2)0.0022 (19)0.0040 (18)−0.0061 (18)
C10.016 (2)0.020 (2)0.019 (2)0.0021 (18)−0.0001 (19)−0.0026 (17)
C20.013 (2)0.024 (2)0.022 (2)−0.0004 (18)−0.0012 (19)−0.0018 (18)
C30.023 (3)0.025 (2)0.025 (2)0.000 (2)0.004 (2)0.0027 (19)
C40.019 (3)0.038 (3)0.017 (2)−0.003 (2)0.0051 (19)−0.0012 (19)
C50.018 (3)0.034 (3)0.020 (2)−0.004 (2)0.0073 (19)−0.0085 (19)
C60.019 (3)0.024 (2)0.026 (2)0.003 (2)0.002 (2)−0.0034 (19)
C110.018 (3)0.018 (2)0.025 (2)−0.0019 (19)0.004 (2)−0.0032 (18)
C210.020 (3)0.018 (2)0.017 (2)−0.0011 (19)0.0033 (19)0.0067 (17)
C410.015 (3)0.023 (2)0.021 (2)0.0011 (19)−0.0008 (19)0.0027 (18)
C420.020 (3)0.022 (2)0.025 (2)0.0016 (19)−0.001 (2)−0.0034 (19)
C430.022 (3)0.033 (3)0.019 (2)0.000 (2)0.005 (2)−0.0027 (19)
C440.019 (3)0.036 (3)0.028 (2)0.003 (2)0.002 (2)0.008 (2)
C450.028 (3)0.016 (2)0.030 (2)0.001 (2)−0.002 (2)0.0041 (19)
C460.022 (3)0.022 (2)0.023 (2)−0.0009 (19)0.002 (2)−0.0012 (18)
Geometric parameters (Å, º) top
C1—C61.391 (6)N51—O511.224 (5)
C1—C21.408 (6)C6—H60.95
C1—C111.499 (6)C41—C421.375 (6)
C11—O111.210 (5)C41—C461.381 (6)
C11—O121.306 (5)C41—N411.458 (5)
O12—H120.92N41—H41A0.8340
C2—C31.385 (6)N41—H41B0.8394
C2—C211.516 (6)N41—H41C0.8375
C21—O221.231 (5)C42—C431.382 (6)
C21—O211.280 (5)C42—H420.95
C3—C41.381 (6)C43—C441.382 (7)
C3—H30.95C43—H430.95
C4—C51.383 (7)C44—C451.379 (7)
C4—H40.95C44—Cl441.751 (5)
C5—C61.378 (6)C45—C461.383 (6)
C5—N511.482 (6)C45—H450.95
N51—O521.222 (5)C46—H460.95
C6—C1—C2119.3 (4)C5—C6—H6120.4
C6—C1—C11117.3 (4)C1—C6—H6120.4
C2—C1—C11123.3 (4)C42—C41—C46121.3 (4)
O11—C11—O12124.6 (4)C42—C41—N41118.7 (4)
O11—C11—C1122.5 (4)C46—C41—N41120.0 (4)
O12—C11—C1112.9 (4)C41—N41—H41A113.9
C11—O12—H12115.1C41—N41—H41B107.4
C3—C2—C1119.6 (4)H41A—N41—H41B102.4
C3—C2—C21118.4 (4)C41—N41—H41C114.9
C1—C2—C21122.0 (4)H41A—N41—H41C109.6
O22—C21—O21126.8 (4)H41B—N41—H41C107.6
O22—C21—C2118.0 (4)C41—C42—C43119.8 (4)
O21—C21—C2115.2 (4)C41—C42—H42120.1
C4—C3—C2121.3 (4)C43—C42—H42120.1
C4—C3—H3119.3C42—C43—C44118.6 (4)
C2—C3—H3119.3C42—C43—H43120.7
C3—C4—C5118.1 (4)C44—C43—H43120.7
C3—C4—H4121.0C45—C44—C43122.1 (4)
C5—C4—H4121.0C45—C44—Cl44118.8 (4)
C6—C5—C4122.4 (4)C43—C44—Cl44119.1 (4)
C6—C5—N51118.3 (4)C44—C45—C46118.8 (4)
C4—C5—N51119.2 (4)C44—C45—H45120.6
O52—N51—O51124.7 (4)C46—C45—H45120.6
O52—N51—C5118.0 (4)C41—C46—C45119.4 (4)
O51—N51—C5117.3 (4)C41—C46—H46120.3
C5—C6—C1119.2 (4)C45—C46—H46120.3
C6—C1—C11—O11−20.3 (7)C4—C5—N51—O523.8 (7)
C2—C1—C11—O11162.1 (5)C6—C5—N51—O516.4 (7)
C6—C1—C11—O12157.5 (4)C4—C5—N51—O51−176.4 (5)
C2—C1—C11—O12−20.1 (6)C4—C5—C6—C10.8 (8)
C6—C1—C2—C30.6 (7)N51—C5—C6—C1177.9 (4)
C11—C1—C2—C3178.1 (4)C2—C1—C6—C5−0.6 (7)
C6—C1—C2—C21−179.2 (4)C11—C1—C6—C5−178.3 (4)
C11—C1—C2—C21−1.6 (7)C46—C41—C42—C43−0.9 (7)
C3—C2—C21—O2297.7 (5)N41—C41—C42—C43−179.7 (4)
C1—C2—C21—O22−82.6 (6)C41—C42—C43—C441.8 (7)
C3—C2—C21—O21−80.3 (5)C42—C43—C44—C45−1.3 (8)
C1—C2—C21—O2199.4 (5)C42—C43—C44—Cl44179.1 (4)
C1—C2—C3—C4−0.6 (7)C43—C44—C45—C46−0.2 (8)
C21—C2—C3—C4179.1 (4)Cl44—C44—C45—C46179.5 (4)
C2—C3—C4—C50.7 (7)C42—C41—C46—C45−0.5 (7)
C3—C4—C5—C6−0.8 (8)N41—C41—C46—C45178.2 (4)
C3—C4—C5—N51−177.9 (4)C44—C45—C46—C411.1 (7)
C6—C5—N51—O52−173.4 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O12—H12···O21i0.921.582.484 (4)169
N41—H41A···O220.831.992.806 (4)166
N41—H41B···O21ii0.841.972.804 (5)173
N41—H41C···O11iii0.842.072.888 (5)166
Symmetry codes: (i) −x+3/2, y+1/2, −z+1/2; (ii) −x+3/2, y−1/2, −z+1/2; (iii) −x+1, y−1, −z+1/2.
(III) 4-Bromoanilinium 2-carboxy-4-nitrobenzoate top
Crystal data top
C6H7BrN+·C8H4NO6−F(000) = 1536
Mr = 383.16Dx = 1.770 Mg m−3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 3305 reflections
a = 12.8292 (6) Åθ = 3.1–27.6°
b = 7.5750 (3) ŵ = 2.89 mm−1
c = 29.8202 (13) ÅT = 120 K
β = 97.0270 (11)°Plate, yellow
V = 2876.2 (2) Å30.26 × 0.04 × 0.02 mm
Z = 8
Data collection top
Nonius KappaCCD
diffractometer		3305 independent reflections
Radiation source: Bruker-Nonius FR91 rotating anode2941 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.041
Detector resolution: 9.091 pixels mm-1θmax = 27.6°, θmin = 3.1°
ϕ and ω scansh = −16→16
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		k = −9→9
Tmin = 0.520, Tmax = 0.944l = −38→38
16011 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.043Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.114H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.0524P)2 + 13.8988P]
where P = (Fo2 + 2Fc2)/3
3304 reflections(Δ/σ)max < 0.001
208 parametersΔρmax = 2.36 e Å−3
0 restraintsΔρmin = −0.76 e Å−3
Crystal data top
C6H7BrN+·C8H4NO6−V = 2876.2 (2) Å3
Mr = 383.16Z = 8
Monoclinic, C2/cMo Kα radiation
a = 12.8292 (6) ŵ = 2.89 mm−1
b = 7.5750 (3) ÅT = 120 K
c = 29.8202 (13) Å0.26 × 0.04 × 0.02 mm
β = 97.0270 (11)°
Data collection top
Nonius KappaCCD
diffractometer		3305 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		2941 reflections with I > 2σ(I)
Tmin = 0.520, Tmax = 0.944Rint = 0.041
16011 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0430 restraints
wR(F2) = 0.114H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.0524P)2 + 13.8988P]
where P = (Fo2 + 2Fc2)/3
3304 reflectionsΔρmax = 2.36 e Å−3
208 parametersΔρmin = −0.76 e Å−3
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Br440.61674 (3)0.69202 (5)0.038369 (11)0.02552 (13)
O110.60484 (17)1.0181 (3)0.28699 (7)0.0212 (5)
O120.69556 (16)0.7854 (3)0.26621 (7)0.0153 (4)
O210.78231 (15)0.4467 (3)0.30440 (7)0.0133 (4)
O220.60830 (16)0.4242 (3)0.28361 (7)0.0163 (4)
O510.6037 (2)1.0871 (4)0.45001 (8)0.0337 (6)
O520.6436 (2)0.8682 (4)0.49603 (8)0.0302 (6)
N410.57854 (19)0.2288 (3)0.20312 (8)0.0131 (5)
N510.6276 (2)0.9318 (4)0.45811 (9)0.0219 (6)
C10.6477 (2)0.7852 (4)0.33989 (9)0.0133 (6)
C20.6679 (2)0.6045 (4)0.34655 (9)0.0123 (5)
C30.6721 (2)0.5335 (4)0.38978 (10)0.0167 (6)
C40.6579 (2)0.6384 (5)0.42661 (10)0.0180 (6)
C50.6390 (2)0.8162 (4)0.41918 (10)0.0178 (6)
C60.6328 (2)0.8919 (4)0.37662 (10)0.0155 (6)
C110.6458 (2)0.8742 (4)0.29474 (9)0.0135 (6)
C210.6857 (2)0.4830 (4)0.30779 (9)0.0115 (5)
C410.5863 (2)0.3418 (4)0.16380 (10)0.0134 (6)
C420.5773 (2)0.2643 (4)0.12130 (10)0.0160 (6)
C430.5858 (2)0.3691 (5)0.08350 (10)0.0186 (6)
C440.6050 (2)0.5476 (4)0.08977 (10)0.0182 (6)
C450.6143 (2)0.6252 (4)0.13219 (11)0.0185 (6)
C460.6047 (2)0.5202 (4)0.16979 (10)0.0157 (6)
H30.68500.41080.39410.020*
H40.66100.58950.45610.022*
H60.61861.01430.37260.019*
H120.69700.83790.23830.023*
H41A0.59760.27820.22800.016*
H41B0.62340.14800.20280.016*
H41C0.51960.18120.20380.016*
H420.56530.14090.11800.019*
H430.57870.31900.05410.022*
H450.62710.74830.13560.022*
H460.61080.57060.19920.019*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br440.02766 (19)0.0304 (2)0.01862 (18)−0.00220 (14)0.00347 (12)0.00980 (13)
O110.0244 (11)0.0198 (12)0.0202 (11)0.0106 (9)0.0067 (9)0.0060 (9)
O120.0180 (10)0.0165 (11)0.0126 (10)0.0032 (8)0.0060 (8)0.0021 (8)
O210.0124 (9)0.0148 (11)0.0129 (9)0.0011 (8)0.0027 (7)−0.0005 (8)
O220.0146 (10)0.0199 (11)0.0142 (10)−0.0038 (8)0.0010 (8)−0.0034 (8)
O510.0473 (16)0.0292 (15)0.0236 (12)0.0161 (12)0.0004 (11)−0.0077 (11)
O520.0404 (14)0.0383 (15)0.0118 (11)−0.0004 (12)0.0023 (10)−0.0025 (10)
N410.0132 (11)0.0139 (13)0.0121 (11)0.0000 (9)0.0013 (9)0.0001 (9)
N510.0218 (13)0.0277 (16)0.0159 (13)0.0025 (11)0.0018 (10)−0.0036 (11)
C10.0099 (12)0.0183 (15)0.0114 (13)0.0012 (11)0.0005 (10)−0.0001 (11)
C20.0083 (11)0.0159 (15)0.0127 (13)−0.0005 (10)0.0011 (9)−0.0014 (11)
C30.0143 (13)0.0212 (16)0.0147 (13)−0.0005 (12)0.0028 (10)0.0004 (12)
C40.0178 (14)0.0260 (17)0.0103 (13)−0.0019 (12)0.0020 (11)−0.0003 (12)
C50.0147 (13)0.0264 (17)0.0126 (14)−0.0020 (12)0.0029 (11)−0.0062 (12)
C60.0120 (12)0.0171 (15)0.0173 (14)0.0026 (11)0.0007 (10)−0.0042 (12)
C110.0119 (12)0.0155 (15)0.0130 (13)0.0000 (11)0.0012 (10)−0.0015 (11)
C210.0145 (12)0.0103 (13)0.0101 (12)−0.0008 (10)0.0028 (10)0.0012 (10)
C410.0099 (12)0.0174 (15)0.0128 (13)0.0015 (10)0.0009 (10)0.0037 (11)
C420.0160 (13)0.0165 (15)0.0153 (14)0.0001 (11)0.0011 (11)−0.0020 (12)
C430.0172 (14)0.0262 (17)0.0127 (13)0.0000 (12)0.0027 (11)−0.0011 (12)
C440.0147 (13)0.0247 (17)0.0154 (14)0.0006 (12)0.0023 (11)0.0065 (12)
C450.0150 (13)0.0162 (15)0.0237 (16)−0.0008 (12)−0.0004 (11)0.0035 (12)
C460.0137 (13)0.0195 (15)0.0135 (13)0.0001 (11)−0.0002 (10)−0.0007 (11)
Geometric parameters (Å, º) top
C1—C61.393 (4)N51—O511.232 (4)
C1—C21.403 (4)C6—H60.95
C1—C111.503 (4)C41—C461.379 (4)
C11—O111.220 (4)C41—C421.389 (4)
C11—O121.310 (3)C41—N411.465 (4)
O12—H120.9239N41—H41A0.8394
C2—C31.392 (4)N41—H41B0.8406
C2—C211.516 (4)N41—H41C0.8403
C21—O221.236 (3)C42—C431.394 (4)
C21—O211.286 (3)C42—H420.95
C3—C41.385 (4)C43—C441.383 (5)
C3—H30.95C43—H430.95
C4—C51.381 (5)C44—C451.387 (4)
C4—H40.95C44—Br441.904 (3)
C5—C61.386 (4)C45—C461.393 (4)
C5—N511.476 (4)C45—H450.95
N51—O521.223 (4)C46—H460.95
C6—C1—C2119.7 (3)C5—C6—H6120.6
C6—C1—C11117.1 (3)C1—C6—H6120.6
C2—C1—C11123.1 (3)C46—C41—C42121.7 (3)
O11—C11—O12124.7 (3)C46—C41—N41119.7 (3)
O11—C11—C1122.0 (3)C42—C41—N41118.5 (3)
O12—C11—C1113.3 (3)C41—N41—H41A113.9
C11—O12—H12115.3C41—N41—H41B107.5
C3—C2—C1119.6 (3)H41A—N41—H41B102.1
C3—C2—C21118.6 (3)C41—N41—H41C114.8
C1—C2—C21121.8 (2)H41A—N41—H41C109.6
O22—C21—O21126.2 (3)H41B—N41—H41C107.9
O22—C21—C2118.6 (2)C41—C42—C43119.4 (3)
O21—C21—C2115.2 (2)C41—C42—H42120.3
C4—C3—C2121.2 (3)C43—C42—H42120.3
C4—C3—H3119.4C44—C43—C42118.6 (3)
C2—C3—H3119.4C44—C43—H43120.7
C5—C4—C3118.0 (3)C42—C43—H43120.7
C5—C4—H4121.0C43—C44—C45122.1 (3)
C3—C4—H4121.0C43—C44—Br44118.9 (2)
C4—C5—C6122.7 (3)C45—C44—Br44119.0 (2)
C4—C5—N51119.0 (3)C44—C45—C46119.1 (3)
C6—C5—N51118.3 (3)C44—C45—H45120.5
O52—N51—O51124.6 (3)C46—C45—H45120.5
O52—N51—C5118.1 (3)C41—C46—C45119.1 (3)
O51—N51—C5117.3 (3)C41—C46—H46120.5
C5—C6—C1118.8 (3)C45—C46—H46120.5
C6—C1—C11—O11−20.4 (4)C6—C5—N51—O52−172.8 (3)
C2—C1—C11—O11162.4 (3)C4—C5—N51—O51−175.1 (3)
C6—C1—C11—O12157.0 (3)C6—C5—N51—O516.4 (4)
C2—C1—C11—O12−20.2 (4)C4—C5—C6—C1−1.0 (4)
C6—C1—C2—C30.5 (4)N51—C5—C6—C1177.5 (3)
C11—C1—C2—C3177.6 (3)C2—C1—C6—C50.4 (4)
C6—C1—C2—C21−179.4 (3)C11—C1—C6—C5−176.9 (3)
C11—C1—C2—C21−2.3 (4)C46—C41—C42—C43−0.7 (4)
C3—C2—C21—O2298.2 (3)N41—C41—C42—C43−179.1 (3)
C1—C2—C21—O22−81.9 (3)C41—C42—C43—C441.1 (4)
C3—C2—C21—O21−79.7 (3)C42—C43—C44—C45−1.0 (5)
C1—C2—C21—O21100.2 (3)C42—C43—C44—Br44−179.9 (2)
C1—C2—C3—C4−0.8 (4)C43—C44—C45—C460.4 (5)
C21—C2—C3—C4179.1 (3)Br44—C44—C45—C46179.3 (2)
C2—C3—C4—C50.2 (4)C42—C41—C46—C450.1 (4)
C3—C4—C5—C60.7 (5)N41—C41—C46—C45178.5 (3)
C3—C4—C5—N51−177.7 (3)C44—C45—C46—C410.1 (4)
C4—C5—N51—O525.7 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O12—H12···O21i0.921.572.481 (3)169
N41—H41A···O220.841.982.806 (3)166
N41—H41B···O21ii0.841.972.811 (3)173
N41—H41C···O11iii0.842.062.888 (3)167
Symmetry codes: (i) −x+3/2, y+1/2, −z+1/2; (ii) −x+3/2, y−1/2, −z+1/2; (iii) −x+1, y−1, −z+1/2.
(IV) 4-Iodoanilinium 2-carboxy-4-nitrobenzoate top
Crystal data top
C6H7IN+·C8H4NO6−F(000) = 1680
Mr = 430.15Dx = 1.949 Mg m−3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 3354 reflections
a = 12.9459 (3) Åθ = 3.1–27.5°
b = 7.5576 (1) ŵ = 2.22 mm−1
c = 30.1790 (6) ÅT = 120 K
β = 96.784 (1)°Plate, colourless
V = 2932.04 (10) Å30.40 × 0.10 × 0.02 mm
Z = 8
Data collection top
Nonius KappaCCD
diffractometer		3354 independent reflections
Radiation source: Bruker-Nonius FR91 rotating anode2941 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.051
Detector resolution: 9.091 pixels mm-1θmax = 27.5°, θmin = 3.1°
ϕ and ω scansh = −16→16
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		k = −9→9
Tmin = 0.471, Tmax = 0.957l = −39→39
16634 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.039Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.160H-atom parameters constrained
S = 1.13 w = 1/[σ2(Fo2) + (0.104P)2 + 15.6247P]
where P = (Fo2 + 2Fc2)/3
3354 reflections(Δ/σ)max < 0.001
210 parametersΔρmax = 2.65 e Å−3
0 restraintsΔρmin = −1.79 e Å−3
Crystal data top
C6H7IN+·C8H4NO6−V = 2932.04 (10) Å3
Mr = 430.15Z = 8
Monoclinic, C2/cMo Kα radiation
a = 12.9459 (3) ŵ = 2.22 mm−1
b = 7.5576 (1) ÅT = 120 K
c = 30.1790 (6) Å0.40 × 0.10 × 0.02 mm
β = 96.784 (1)°
Data collection top
Nonius KappaCCD
diffractometer		3354 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		2941 reflections with I > 2σ(I)
Tmin = 0.471, Tmax = 0.957Rint = 0.051
16634 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0390 restraints
wR(F2) = 0.160H-atom parameters constrained
S = 1.13 w = 1/[σ2(Fo2) + (0.104P)2 + 15.6247P]
where P = (Fo2 + 2Fc2)/3
3354 reflectionsΔρmax = 2.65 e Å−3
210 parametersΔρmin = −1.79 e Å−3
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
I440.61731 (3)0.69745 (4)0.036131 (11)0.01968 (17)
O110.6038 (3)1.0038 (5)0.28572 (12)0.0200 (8)
O120.6966 (3)0.7720 (5)0.26612 (12)0.0139 (7)
O210.7804 (2)0.4323 (4)0.30370 (11)0.0120 (6)
O220.6079 (3)0.4100 (5)0.28335 (11)0.0152 (7)
O510.6043 (3)1.0773 (5)0.44712 (13)0.0263 (9)
O520.6488 (3)0.8605 (6)0.49281 (13)0.0258 (9)
N410.5789 (3)0.2136 (5)0.20371 (14)0.0121 (8)
N510.6308 (3)0.9228 (6)0.45517 (15)0.0180 (9)
C10.6475 (4)0.7735 (7)0.33863 (16)0.0124 (9)
C20.6671 (3)0.5930 (6)0.34531 (16)0.0127 (9)
C30.6720 (4)0.5214 (7)0.38839 (16)0.0139 (9)
C40.6593 (4)0.6279 (7)0.42440 (17)0.0162 (10)
C50.6412 (4)0.8059 (7)0.41702 (18)0.0163 (11)
C60.6332 (4)0.8812 (7)0.37498 (16)0.0141 (9)
C110.6463 (4)0.8603 (7)0.29378 (16)0.0130 (9)
C220.6844 (4)0.4688 (6)0.30713 (15)0.0124 (9)
C410.5858 (4)0.3271 (6)0.16485 (17)0.0127 (9)
C420.5785 (4)0.2488 (7)0.12331 (16)0.0146 (9)
C430.5873 (4)0.3537 (7)0.08557 (17)0.0168 (10)
C440.6042 (4)0.5350 (7)0.09227 (16)0.0153 (10)
C450.6123 (4)0.6108 (7)0.13403 (18)0.0162 (10)
C460.6031 (4)0.5056 (7)0.17115 (16)0.0145 (9)
H30.68410.39830.39280.017*
H40.66300.57980.45360.019*
H60.61831.00360.37090.017*
H120.68690.81940.24080.021*
H41A0.59350.27820.22910.018*
H41B0.62540.12330.20360.018*
H41C0.51340.16860.20260.018*
H420.56770.12490.12030.018*
H430.58200.30340.05650.020*
H450.62410.73440.13750.019*
H460.60860.55570.20020.017*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
I440.0206 (2)0.0229 (3)0.0159 (2)−0.00126 (12)0.00336 (15)0.00659 (12)
O110.0236 (19)0.018 (2)0.0196 (19)0.0089 (16)0.0084 (15)0.0040 (16)
O120.0198 (18)0.0138 (16)0.0093 (16)0.0022 (14)0.0063 (14)0.0034 (13)
O210.0118 (15)0.0130 (16)0.0114 (15)0.0008 (13)0.0027 (12)−0.0015 (13)
O220.0145 (16)0.0184 (18)0.0131 (16)−0.0032 (14)0.0040 (13)−0.0028 (14)
O510.037 (2)0.0212 (19)0.0205 (19)0.0093 (17)0.0007 (17)−0.0071 (16)
O520.034 (2)0.031 (2)0.0128 (18)−0.0021 (19)0.0016 (16)−0.0026 (17)
N410.0102 (19)0.015 (2)0.0106 (19)−0.0014 (15)0.0002 (15)0.0016 (15)
N510.016 (2)0.023 (2)0.016 (2)−0.0011 (17)0.0030 (16)−0.0070 (18)
C10.010 (2)0.018 (2)0.010 (2)0.0019 (18)0.0027 (17)−0.0006 (18)
C20.009 (2)0.015 (2)0.014 (2)−0.0008 (17)0.0036 (16)−0.0036 (18)
C30.013 (2)0.015 (2)0.015 (2)−0.0017 (18)0.0044 (17)−0.0028 (18)
C40.012 (2)0.025 (3)0.011 (2)−0.002 (2)0.0004 (17)0.000 (2)
C50.014 (2)0.023 (3)0.011 (2)−0.0004 (18)0.0016 (19)−0.0060 (18)
C60.012 (2)0.014 (2)0.015 (2)0.0013 (18)0.0022 (17)−0.0030 (19)
C110.012 (2)0.014 (2)0.013 (2)0.0002 (18)0.0017 (17)−0.0025 (18)
C220.018 (2)0.010 (2)0.010 (2)−0.0002 (18)0.0044 (17)0.0032 (17)
C410.011 (2)0.014 (2)0.013 (2)0.0009 (17)0.0016 (18)0.0013 (18)
C420.017 (2)0.015 (2)0.012 (2)−0.0005 (19)0.0011 (18)0.000 (2)
C430.017 (2)0.023 (2)0.010 (2)−0.001 (2)0.0004 (18)0.000 (2)
C440.013 (2)0.021 (2)0.012 (2)0.0023 (19)0.0023 (17)0.0090 (19)
C450.015 (2)0.013 (2)0.021 (2)−0.0011 (18)0.0019 (19)0.0051 (19)
C460.014 (2)0.017 (2)0.012 (2)−0.0001 (19)0.0027 (17)−0.0009 (18)
Geometric parameters (Å, º) top
C1—C61.396 (7)N51—O511.233 (6)
C1—C21.398 (7)C6—H60.95
C1—C111.502 (7)C41—C461.377 (7)
C11—O111.227 (6)C41—C421.379 (7)
C11—O121.302 (6)C41—N411.465 (6)
C2—C31.403 (7)N41—H41A0.91
C2—C221.523 (6)N41—H41B0.91
C22—O221.235 (6)N41—H41C0.91
C22—O211.289 (6)C42—C431.403 (7)
O12—H120.84C42—H420.95
C3—C41.378 (7)C43—C441.398 (8)
C3—H30.95C43—H430.95
C4—C51.380 (8)C44—C451.377 (7)
C4—H40.95C44—I442.115 (5)
C5—C61.383 (7)C45—C461.390 (7)
C5—N511.470 (6)C45—H450.95
N51—O521.226 (6)C46—H460.95
C6—C1—C2119.6 (4)C5—C6—H6120.7
C6—C1—C11117.7 (4)C1—C6—H6120.7
C2—C1—C11122.6 (4)C46—C41—C42122.6 (5)
O11—C11—O12124.9 (5)C46—C41—N41119.2 (5)
O11—C11—C1121.4 (4)C42—C41—N41118.2 (4)
O12—C11—C1113.6 (4)C41—N41—H41A109.5
C1—C2—C3119.8 (4)C41—N41—H41B109.5
C1—C2—C22122.2 (4)H41A—N41—H41B109.5
C3—C2—C22118.0 (4)C41—N41—H41C109.5
O22—C22—O21126.2 (4)H41A—N41—H41C109.5
O22—C22—C2118.8 (4)H41B—N41—H41C109.5
O21—C22—C2114.9 (4)C41—C42—C43119.5 (5)
C11—O12—H12109.5C41—C42—H42120.3
C4—C3—C2120.6 (5)C43—C42—H42120.3
C4—C3—H3119.7C44—C43—C42117.5 (5)
C2—C3—H3119.7C44—C43—H43121.2
C3—C4—C5118.4 (5)C42—C43—H43121.2
C3—C4—H4120.8C45—C44—C43122.2 (4)
C5—C4—H4120.8C45—C44—I44119.1 (4)
C4—C5—C6122.8 (5)C43—C44—I44118.6 (4)
C4—C5—N51119.3 (5)C44—C45—C46119.7 (5)
C6—C5—N51117.9 (4)C44—C45—H45120.2
O52—N51—O51124.3 (5)C46—C45—H45120.2
O52—N51—C5118.0 (5)C41—C46—C45118.5 (5)
O51—N51—C5117.6 (4)C41—C46—H46120.7
C5—C6—C1118.6 (5)C45—C46—H46120.7
C6—C1—C11—O11−22.0 (7)C6—C5—N51—O52−172.4 (5)
C2—C1—C11—O11161.0 (5)C4—C5—N51—O51−172.9 (5)
C6—C1—C11—O12155.7 (4)C6—C5—N51—O517.8 (7)
C2—C1—C11—O12−21.3 (7)C4—C5—C6—C1−2.2 (8)
C6—C1—C2—C30.1 (7)N51—C5—C6—C1177.1 (4)
C11—C1—C2—C3177.1 (4)C2—C1—C6—C51.4 (7)
C6—C1—C2—C22−179.4 (4)C11—C1—C6—C5−175.6 (5)
C11—C1—C2—C22−2.5 (7)C46—C41—C42—C43−1.0 (8)
C1—C2—C22—O22−81.6 (6)N41—C41—C42—C43−178.5 (4)
C3—C2—C22—O2298.8 (5)C41—C42—C43—C440.6 (7)
C1—C2—C22—O21100.0 (5)C42—C43—C44—C450.1 (8)
C3—C2—C22—O21−79.6 (5)C42—C43—C44—I44−179.8 (4)
C1—C2—C3—C4−1.1 (7)C43—C44—C45—C46−0.3 (8)
C22—C2—C3—C4178.5 (4)I44—C44—C45—C46179.5 (4)
C2—C3—C4—C50.4 (7)C42—C41—C46—C450.8 (8)
C3—C4—C5—C61.3 (8)N41—C41—C46—C45178.3 (4)
C3—C4—C5—N51−178.0 (4)C44—C45—C46—C41−0.1 (7)
C4—C5—N51—O527.0 (7)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O12—H12···O21i0.841.692.479 (5)156
N41—H41A···O220.911.912.812 (5)173
N41—H41B···O21ii0.911.922.826 (5)174
N41—H41C···O11iii0.912.032.896 (5)159
Symmetry codes: (i) −x+3/2, y+1/2, −z+1/2; (ii) −x+3/2, y−1/2, −z+1/2; (iii) −x+1, y−1, −z+1/2.

Experimental details

(I)(II)(III)(IV)
Crystal data
Chemical formulaC6H8N+·C8H4NO6−C6H7ClN+·C8H4NO6−C6H7BrN+·C8H4NO6−C6H7IN+·C8H4NO6−
Mr304.26338.70383.16430.15
Crystal system, space groupMonoclinic, C2/cMonoclinic, C2/cMonoclinic, C2/cMonoclinic, C2/c
Temperature (K)120120120120
a, b, c (Å)12.8131 (10), 7.5521 (6), 28.114 (2)12.7725 (16), 7.5825 (7), 29.595 (3)12.8292 (6), 7.5750 (3), 29.8202 (13)12.9459 (3), 7.5576 (1), 30.1790 (6)
β (°) 98.13 (3) 97.202 (5) 97.0270 (11) 96.784 (1)
V (Å3)2693.1 (4)2843.6 (5)2876.2 (2)2932.04 (10)
Z8888
Radiation typeMo KαMo KαMo KαMo Kα
µ (mm−1)0.120.302.892.22
Crystal size (mm)0.14 × 0.10 × 0.020.36 × 0.09 × 0.020.26 × 0.04 × 0.020.40 × 0.10 × 0.02
Data collection
DiffractometerNonius KappaCCD
diffractometer		Nonius KappaCCD
diffractometer		Nonius KappaCCD
diffractometer		Nonius KappaCCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2003)		Multi-scan
(SADABS; Sheldrick, 2003)		Multi-scan
(SADABS; Sheldrick, 2003)		Multi-scan
(SADABS; Sheldrick, 2003)
Tmin, Tmax0.980, 0.9980.910, 0.9940.520, 0.9440.471, 0.957
No. of measured, independent and
observed [I > 2σ(I)] reflections		13132, 2656, 1474 7613, 2342, 1887 16011, 3305, 2941 16634, 3354, 2941
Rint0.0970.0520.0410.051
(sin θ/λ)max (Å−1)0.6190.5950.6510.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.077, 0.210, 1.03 0.072, 0.190, 1.13 0.043, 0.114, 1.08 0.039, 0.160, 1.13
No. of reflections2656234233043354
No. of parameters200208208210
H-atom treatmentH-atom parameters constrainedH-atom parameters constrainedH-atom parameters constrainedH-atom parameters constrained
w = 1/[σ2(Fo2) + (0.0871P)2 + 5.7738P]
where P = (Fo2 + 2Fc2)/3		 w = 1/[σ2(Fo2) + (0.0614P)2 + 21.7547P]
where P = (Fo2 + 2Fc2)/3		 w = 1/[σ2(Fo2) + (0.0524P)2 + 13.8988P]
where P = (Fo2 + 2Fc2)/3		 w = 1/[σ2(Fo2) + (0.104P)2 + 15.6247P]
where P = (Fo2 + 2Fc2)/3
Δρmax, Δρmin (e Å−3)0.43, −0.300.75, −0.402.36, −0.762.65, −1.79

Computer programs: COLLECT (Hooft, 1999), DENZO (Otwinowski & Minor, 1997) and COLLECT, DENZO and COLLECT, OSCAIL (McArdle, 2003) and SHELXS97 (Sheldrick, 1997), OSCAIL and SHELXL97 (Sheldrick, 1997), PLATON (Spek, 2003), SHELXL97 and PRPKAPPA (Ferguson, 1999).

Hydrogen-bond geometry (Å, º) for (I) top
D—H···AD—HH···AD···AD—H···A
O12—H12···O21i1.001.482.476 (4)176
N41—H41A···O220.911.892.799 (4)173
N41—H41B···O21ii0.911.922.828 (4)172
N41—H41C···O11iii0.912.022.884 (4)158
Symmetry codes: (i) −x+3/2, y+1/2, −z+1/2; (ii) −x+3/2, y−1/2, −z+1/2; (iii) −x+1, y−1, −z+1/2.
Hydrogen-bond geometry (Å, º) for (II) top
D—H···AD—HH···AD···AD—H···A
O12—H12···O21i0.921.582.484 (4)169
N41—H41A···O220.831.992.806 (4)166
N41—H41B···O21ii0.841.972.804 (5)173
N41—H41C···O11iii0.842.072.888 (5)166
Symmetry codes: (i) −x+3/2, y+1/2, −z+1/2; (ii) −x+3/2, y−1/2, −z+1/2; (iii) −x+1, y−1, −z+1/2.
Hydrogen-bond geometry (Å, º) for (III) top
D—H···AD—HH···AD···AD—H···A
O12—H12···O21i0.921.572.481 (3)169
N41—H41A···O220.841.982.806 (3)166
N41—H41B···O21ii0.841.972.811 (3)173
N41—H41C···O11iii0.842.062.888 (3)167
Symmetry codes: (i) −x+3/2, y+1/2, −z+1/2; (ii) −x+3/2, y−1/2, −z+1/2; (iii) −x+1, y−1, −z+1/2.
Hydrogen-bond geometry (Å, º) for (IV) top
D—H···AD—HH···AD···AD—H···A
O12—H12···O21i0.841.692.479 (5)156
N41—H41A···O220.911.912.812 (5)173
N41—H41B···O21ii0.911.922.826 (5)174
N41—H41C···O11iii0.912.032.896 (5)159
Symmetry codes: (i) −x+3/2, y+1/2, −z+1/2; (ii) −x+3/2, y−1/2, −z+1/2; (iii) −x+1, y−1, −z+1/2.
Selected geometric parameters (Å, °) for compounds (I)–(IV) top
Parameter(I)(II)(III)(IV)
C11-O111.211 (5)1.210 (5)1.220 (4)1.277 (6)
C11-O121.308 (5)1.306 (5)1.310 (3)1.302 (6)
C21-O211.283 (4)1.280 (5)1.286 (3)1.289 (6)
C21-O221.277 (5)1.231 (5)1.236 (3)1.235 (6)
C2-C1-C11-O11163.1 (4)162.1 (5)162.4 (3)161.0 (5)
C1-C2-C21-O21101.1 (4)99.4 (5)100.2 (3)100.0 (5)
C4-C5-N51-O51173.5 (4)-176.4 (5)-175.1 (3)-172.9 (5)
Short intermolecular C44-X44···O51i contacts (Å, °) for compounds (I) - (IV) top
CompoundC-XX···OiC···OiC-X···OiX···Oi-Ni
(I) (X = H)0.952.553.477 (6)167103
(II) (X = Cl)1.751 (5)3.109 (4)4.849 (6)171.8 (2)111.0 (3)
(III) (X = Br)1.904 (3)3.108 (3)5.001 (4)172.0 (2)111.2 (2)
(IV) (X = I)2.115 (5)3.168 (4)5.270 (4)171.8 (2)110.9 (3)
Symmetry code: (i) x, 2 − y, −0.5 + z.
 

Acknowledgements

X-ray data were collected at the EPSRC X-ray Crystallographic Service, University of Southampton, England; the authors thank the staff of the Service for all their help and advice. JLW thanks CNPq and FAPERJ for financial support.

References

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ISSN: 2053-2296
Volume 61| Part 5| May 2005| Pages o276-o280
doi:10.1107/S0108270105007286
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