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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 62| Part 1| January 2006| Pages o26-o29
doi:10.1107/S0108270105038631

Simple chains in methyl 3,5-di­nitro­benzoate, isolated mol­ecules in iso­propyl 3,5-di­nitro­benzoate, and a three-dimensional framework containing double and sextuple helices in benzyl 3,5-di­nitro­benzoate, all at 120 K

CROSSMARK_Color_square_no_text.svg
Thatyana R. A. Vasconcelos,a Marcus V. N. de Souza,a Solange M. S. V. Wardell,a James L. Wardell,b John N. Lowc and Christopher Glidewelld*

aComplexo Tecnológico de Medicamentos Farmanguinhos, Av. Comandante Guaranys 447, Jacarepaguá, Rio de Janeiro, RJ, Brazil, bInstituto de Química, Departamento de Química Inorgânica, Universidade Federal do Rio de Janeiro, CP 68563, 21945-970 Rio de Janeiro, RJ, Brazil, cDepartment of Chemistry, University of Aberdeen, Meston Walk, Old Aberdeen AB24 3UE, Scotland, and dSchool of Chemistry, University of St Andrews, Fife KY16 9ST, Scotland
*Correspondence e-mail: cg@st-andrews.ac.uk

(Received 21 November 2005; accepted 22 November 2005; online 16 December 2005)

Mol­ecules of methyl 3,5-dinitro­benzoate, C8H6N2O6, are linked into C(7) chains by a single nearly linear C—H⋯O hydrogen bond, but there are no direction-specific inter­actions in the structure of isopropyl 3,5-dinitro­benzoate, C10H10N2O6. In benzyl 3,5-dinitro­benzoate, C14H10N2O6, the mol­ecules are linked by four independent C—H⋯O hydrogen bonds into a complex three-dimensional framework structure, in which it is possible to identify simple substructures in the form of cyclic centrosymmetric dimers, double helices and sextuple helices.

Similar articles

Comment

We report here the structures of methyl, isopropyl and benzyl 3,5-dinitro­benzoate, (I)–(III)[link], respectively, derived from low-temperature diffraction data. It has been recognized since the early days of experimental organic chemistry that the 3,5-nitro­benzoate esters of simple alcohols are crystalline solids

[Scheme 1]
that are very readily purified and crystallized, and indeed these crystalline esters were for many decades utilized as an aid to identification of such alcohols by means of their sharp and characteristic melting temperatures. The structures of a few of these esters have been the subject of isolated reports, including the ethyl ester (Hughes & Trotter, 1971[Hughes, D. L. & Trotter, J. (1971). J. Chem. Soc. A, pp. 2358-2361.]) and the 2,2-dimethyl­butyl ester, where Z′ = 2 (Sax et al., 1976[Sax, M., Rodrigues, M., Blank, G., Wood, M. K. & Pletcher, J. (1976). Acta Cryst. B32, 1953-1956.]); both of these structure determinations were based on the use of diffraction data collected at ambient temperature. More recently, the structures of the methyl ester, (I)[link] (Jin & Xiao, 2000b), the n-propyl ester, where Z′ = 2 (Jin & Xiao, 2005c[Jin, L.-F. & Xiao, F.-P. (2005c). Acta Cryst. E61, o1826-o1827.]), and the isopropyl ester, (II)[link] (Jin & Xiao, 2005a[Jin, L.-F. & Xiao, F.-P. (2005a). Acta Cryst. E61, o1269-o1270.]), have been reported, also using diffraction data collected at ambient temperature. The structure of (I)[link] was reported to contain π-stacked mol­ecules related by translation along [100], with inter­molecular C⋯C contacts as short as 3.440 (4) Å, despite the a repeat vector of 4.5833 (15) Å; no hydrogen bonds were reported in this compound. Although the unit-cell dimensions, the space group and the atomic coordinates for (I)[link] indicate that no phase change has occurred between ambient temperature and 120 K, we find no π–π stacking in (I)[link]; however, a nearly linear C—H⋯O hydrogen bond is present, in contrast to the findings reported previously (Jin & Xiao, 2005b[Jin, L.-F. & Xiao, F.-P. (2005b). Acta Cryst. E61, o1276-o1277.]).

The mol­ecule of (I)[link] (Fig. 1[link]) is effectively planar, apart from the H atoms of the methyl group, as shown by the leading torsion angles (Table 3[link]). In (II)[link] and (III)[link] (Figs. 2[link] and 3[link]), the ester fragment up to and including atom C12 is effectively coplanar with the adjacent aryl ring, but in (III)[link] in particular, the remaining torsion angles indicate a markedly non-planar conformation. The bond distances show no unusual values, but in each compound the inter­nal angles at atoms C3 and C5, which are ipso to the nitro groups, are significantly larger than the corresponding angle at C2, which is ipso to the ester group.

There are no direction-specific inter­molecular inter­actions in the structure of (II)[link], but the mol­ecules of (I)[link] are linked into simple C(7) chains by a single C—H⋯O hydrogen bond (Table 1[link]). Atom C4 in the mol­ecule at (x, y, z) acts as a hydrogen-bond donor to carbonyl atom O1 in the mol­ecule at ([{3\over 2}] + x, [{3\over 2}] − y, [{1\over 2}] + z), so forming a C(7) (Bernstein et al., 1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]) chain running parallel to the [301] direction and generated by the n-glide plane at y = [3\over 4] (Fig. 4[link]). Two such chains, related to one another by inversion, pass through each unit cell, but there are no direction-specific inter­actions between adjacent chains; in particular, C—H⋯π(arene) hydrogen bonds and aromatic π–π stacking inter­actions are both absent. The shortest ring-centroid separation, which involves the mol­ecules at (x, y, z) and ([{1\over 2}] + x, [{3\over 2}] − y, [{1\over 2}] + z), is 5.670 (2) Å and is clearly too large for effective π–π stacking.

The mol­ecules of (III)[link] are linked by four independent C—H⋯O hydrogen bonds (Table 2[link]) into a three-dimensional framework of considerable complexity. However, it is possible to identify several simple substructures, each generated by a limited number of hydrogen bonds. The formation of the framework is most simply analysed in terms of one finite zero-dimensional motif, which can be regarded as the basic building block; this motif is formed by the concerted action of two of the hydrogen bonds and two independent chain motifs, each containing a single hydrogen bond, one of which generates a double helix while the other generates a sextuple helix.

In the first substructure, atoms C6 and C12 in the mol­ecule at (x, y, z) act as hydrogen-bond donors, respectively, to atoms O1 and O52 in the mol­ecule at (1 − x, 1 − y, −z), so generating a centrosymmetric dimer centred at ([1\over 2], [1\over2], 0), in which inversion-related pairs of hydrogen bonds generate R22(10) and R22(18) rings (Fig. 5[link]). In the second substructure, this time one-dimensional as opposed to zero-dimensional, atom C2 in the mol­ecule at (x, y, z) acts as a hydrogen-bond donor to atom O32 in the mol­ecule at (1 − y, −[{1\over 2}] + x, [{1\over 2}] + z), while atom C2 at (1 − y, −[{1\over 2}] + x, [{1\over 2}] + z) in turn acts as a donor to atom O32 at ([{3\over 2}] − x, [{1\over 2}] − y, 1 + z). Propagation of this hydrogen bond thus generates a C(5) helical chain running parallel to the [001] direction and generated by the 42 screw axis along ([3\over4], [1\over4], z) (Fig. 6[link]). Because the screw axis is of the 42 type, this chain links the mol­ecules at (x, y, z) and (x, y, 2 + z), so that complete definition of this substructure requires two coaxial helices offset by a unit translation along [001].

The combination of this helical chain (Fig. 6[link]) with the centrosymmetric dimer motif (Fig. 5[link]) then links each helical chain to four adjacent helical chains; for example, the helix along ([3\over4], [1\over4], z) is directly linked in this way to those along ([1\over4], [3\over4], z), ([5\over4], [3\over4], z), ([1\over4], −[1\over4], z) and ([5\over4], −[1\over4], z), so forming a continuous three-dimensional framework. Because of the double-helical nature of the [001] chain, there are in fact two such frameworks, intimately inter­woven.

In addition, there is a fourth C—H⋯O hydrogen bond, whose action in isolation is to generate a sextuple helix of C(11) chains (Fig. 7[link]), but which in combination with the first chain-forming hydrogen bond links the two inter­woven frameworks into a single continuous structure. Atom C22 in the mol­ecule at (x, y, z) acts as a hydrogen-bond donor to atom O51 in the mol­ecule at (1 − y, −[{1\over 2}] + x, [{3\over 2}] + z), and atom C22 at (1 − y, −[{1\over 2}] + x, [{3\over 2}] + z) likewise acts as a donor to atom O51 at ([{3\over 2}] − x, [{1\over 2}] − y, 3 + z), and thence via ([{1\over 2}] + y, 1 − x, [9 \over2] + z) to (x, y, 6 + z), so generating the sextuple helix. At the same time, atom C2 in the mol­ecule at (1 − y, −[{1\over 2}] + x, [{3\over 2}] + z) acts as a hydrogen-bond donor to atom O32 in the mol­ecule at ([{3\over 2}] − x, [{1\over 2}] − y, 2 + z), thereby linking the two coaxial C(5) helices along ([3\over4], [1\over4], z) and hence linking the two frameworks.

[Figure 1]
Figure 1
The mol­ecule of (I)[link], showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2]
Figure 2
The mol­ecule of (II)[link], showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 3]
Figure 3
The mol­ecule of (III)[link], showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 4]
Figure 4
Part of the crystal structure of (I)[link], showing the formation of a C(7) chain along [301]. For the sake of clarity, H atoms not involved in the motif shown have been omitted. Atoms marked with an asterisk (*) or a hash (#) are at the symmetry positions ([{3\over 2}] + x, [{3\over 2}] − y, [{1\over 2}] + z) and (−[{3\over 2}] + x, [{3\over 2}] − y, −[{1\over 2}] + z), respectively.
[Figure 5]
Figure 5
Part of the crystal structure of (III)[link], showing the formation of a centrosymmetric dimer. For the sake of clarity, H atoms bonded to C atoms not involved in the motif shown have been omitted. Atoms marked with an asterisk (*) are at the symmetry position (1 − x, 1 − y, −z).
[Figure 6]
Figure 6
A stereoview of part of the crystal structure of (III)[link], showing a hydrogen-bonded helical C(5) chain generated by the 42 screw axis along ([3\over4], [1\over4], z) and forming one strand of a double helix. For the sake of clarity, H atoms not involved in the motif shown have been omitted.
[Figure 7]
Figure 7
A stereoview of part of the crystal structure of (III)[link], showing a hydrogen-bonded helical C(11) chain generated by the 42 screw axis along ([3\over4], [1\over4], z) and forming one strand of a sextuple helix. For the sake of clarity, H atoms not involved in the motif shown have been omitted.

Experimental

Samples of compounds (I)–(III) were prepared from 3,5-dinitro­benzoic acid according to a published procedure (Vogel, 1977[Vogel, A. I. (1977). Elementary Practical Organic Chemistry, Part 2, Qualitative Organic Analysis, 2nd ed., p. 75. London: Longman.]). The compounds had the expected NMR and IR spectra, and the melting points were in agreement with those reported previously (Vogel, 1977[Vogel, A. I. (1977). Elementary Practical Organic Chemistry, Part 2, Qualitative Organic Analysis, 2nd ed., p. 75. London: Longman.]). Crystals suitable for single-crystal X-ray diffraction were grown by slow evaporation of solutions in ethanol.

Compound (I)[link]

Crystal data

  • C8H6N2O6

  • Mr = 226.15

  • Monoclinic, P 21 /n

  • a = 4.5664 (4) Å

  • b = 18.727 (2) Å

  • c = 10.8416 (10) Å

  • β = 101.787 (6)°

  • V = 907.57 (15) Å3

  • Z = 4

  • Dx = 1.655 Mg m−3

  • Mo Kα radiation

  • Cell parameters from 2070 reflections

  • θ = 2.9–27.6°

  • μ = 0.14 mm−1

  • T = 120 (2) K

  • Lath, colourless

  • 0.52 × 0.12 × 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 = 0.935, Tmax = 0.997

  • 9551 measured reflections

  • 2070 independent reflections

  • 1319 reflections with I > 2σ(I)

  • Rint = 0.060

  • θmax = 27.6°

  • h = −5 → 5

  • k = −24 → 24

  • l = −14 → 14
Refinement

  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.058

  • wR(F2) = 0.174

  • S = 1.09

  • 2070 reflections

  • 146 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(Fo2) + (0.0823P)2 + 0.2307P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max < 0.001

  • Δρmax = 0.25 e Å−3

  • Δρmin = −0.29 e Å−3

Table 1
Hydrogen-bond geometry (Å, °) for (I)[link]

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C4—H4⋯O1i 0.95 2.46 3.399 (3) 171
Symmetry code: (i) [x+{\script{3\over 2}}, -y+{\script{3\over 2}}, z+{\script{1\over 2}}].

Compound (II)[link]

Crystal data

  • C10H10N2O6

  • Mr = 254.20

  • Monoclinic, P 21 /n

  • a = 9.7037 (3) Å

  • b = 5.7152 (2) Å

  • c = 20.4739 (9) Å

  • β = 95.504 (2)°

  • V = 1130.22 (7) Å3

  • Z = 4

  • Dx = 1.494 Mg m−3

  • Mo Kα radiation

  • Cell parameters from 2596 reflections

  • θ = 3.8–27.5°

  • μ = 0.13 mm−1

  • T = 120 (2) K

  • Block, colourless

  • 0.42 × 0.40 × 0.38 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 = 0.944, Tmax = 0.954

  • 10022 measured reflections

  • 2596 independent reflections

  • 2045 reflections with I > 2σ(I)

  • Rint = 0.031; θmax = 27.5°

  • h = −12 → 12

  • k = −7 → 7

  • l = −24 → 26
Refinement

  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.039

  • wR(F2) = 0.105

  • S = 1.05

  • 2596 reflections

  • 165 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(Fo2) + (0.0561P)2 + 0.2191P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max = 0.001

  • Δρmax = 0.30 e Å−3

  • Δρmin = −0.34 e Å−3

Compound (III)[link]

Crystal data

  • C14H10N2O6

  • Mr = 302.24

  • Tetragonal, P 42 /n

  • a = 20.8531 (5) Å

  • c = 6.0377 (2) Å

  • V = 2625.50 (12) Å3

  • Z = 8

  • Dx = 1.529 Mg m−3

  • Mo Kα radiation

  • Cell parameters from 3000 reflections

  • θ = 3.1–27.5°

  • μ = 0.12 mm−1

  • T = 120 (2) K

  • Needle, colourless

  • 0.22 × 0.06 × 0.04 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 = 0.978, Tmax = 0.995

  • 18873 measured reflections

  • 3000 independent reflections

  • 2413 reflections with I > 2σ(I)

  • Rint = 0.053; θmax = 27.5°

  • h = −27 → 26

  • k = −16 → 27

  • l = −7 → 7
Refinement

  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.103

  • S = 1.05

  • 3000 reflections

  • 199 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(Fo2) + (0.0355P)2 + 1.5651P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max = 0.001

  • Δρmax = 0.24 e Å−3

  • Δρmin = −0.23 e Å−3

Table 2
Hydrogen-bond geometry (Å, °) for (III)[link]

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C2—H2⋯O32ii 0.95 2.52 3.460 (2) 170
C6—H6⋯O1iii 0.95 2.57 3.493 (2) 164
C12—H12A⋯O52iii 0.99 2.56 3.474 (2) 154
C22—H22⋯O51iv 0.95 2.57 3.360 (2) 140
Symmetry codes: (ii) [-y+1, x-{\script{1\over 2}}, z+{\script{1\over 2}}]; (iii) -x+1, -y+1, -z; (iv) [-y+1, x-{\script{1\over 2}}, z+{\script{3\over 2}}].

Table 3
Selected angles and torsion angles (°) for compounds (I)–(III)

    (I) (II) (III)
C6—C1—C2   120.2 (2) 120.34 (11) 120.82 (14)
C2—C3—C4   123.3 (2) 123.34 (11) 122.94 (15)
C4—C5—C6   123.3 (2) 122.58 (12) 123.37 (15)
C2—C1—C11—O11   2.0 (3) −6.24 (16) 15.2 (2)
C1—C11—O11—C12   179.74 (19) −176.88 (9) 177.03 (12)
C11—O11—C12—C13   – 152.12 (12) –
C11—O11—C12—C14   – −85.33 (13) –
C11—O11—C12—C21   – – 93.65 (16)
O11—C12—C21—C22   – – 89.93 (7)
C2—C3—N3—O31   0.2 (3) −4.88 (16) 9.1 (2)
C4—C5—N5—O51   4.2 (3) 6.13 (16) 7.5 (2)

For each of compounds (I)[link] and (II)[link], the space group P21/n was uniquely assigned from the systematic absences. For compound (III)[link], the space group P42/n was uniquely assigned from the systematic absences, and the setting adopted had the origin coincident with a centre of inversion. All H atoms were located in difference maps and then treated as riding atoms, with C—H distances of 0.95 (aromatic), 0.98 (meth­yl), 0.99 (CH2) or 1.00 Å (aliphatic CH), and with Uiso(H) values of 1.2Ueq(C), or 1.5Ueq(C) for the methyl groups.

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; program(s) used to solve structure: 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.]); program(s) used to refine structure: 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. DOI: 10.1107/S0108270105038631/sk1889sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S0108270105038631/sk1889Isup2.hkl

Structure factors: contains datablock II. DOI: 10.1107/S0108270105038631/sk1889IIsup3.hkl

Structure factors: contains datablock III. DOI: 10.1107/S0108270105038631/sk1889IIIsup4.hkl


Comment top

We report here the structures of methyl, isopropyl and benzyl 3,5-dinitrobenzoate, (I)–(III), respectively, derived from low-temperature diffraction data. It has been recognized since the early days of experimental organic chemistry that the 3,5-nitrobenzoate esters of simple alcohols are crystalline solids that are very readily purified and crystallized, and indeed, these crystalline esters were for many decades utilized as an aid to identification of such alcohols by means of their sharp and characteristic melting temperatures. The structures of a few of these esters have been the subject of isolated reports, including the ethyl ester (Hughes & Trotter, 1971) and the 2,2-dimethylbutyl ester, where Z' = 2 (Sax et al., 1976); both of these structure determinations were based on the use of diffraction data collected at ambient temperature. More recently, the structures of the methyl ester (I) (Jin & Xiao, 2000b), the n-propyl ester, where Z' = 2 (Jin & Xiao, 2005c), and the iso-propyl ester, (II) (Jin & Xiao, 2005a), have been reported, also using diffraction data collected at ambient temperature. The structure of the methyl ester (I) was reported to contain π-stacked molecules related by translation along [100] with intermolecular C···C contacts as short as 3.440 (4) Å, despite the a repeat vector of 4.5833 (15) Å; no hydrogen bonds were reported in this compound. Although the unit-cell dimensions, the space group and the atomic coordinates for (I) indicate that no phase change has occurred between ambient temperature and 120 K, we find no π–π stacking in (I), but that nearly linear C—H···O hydrogen bond is present, in contrast to the findings reported previously (Jin & Xiao, 2005b).

The molecule of (I) (Fig. 1) is effectively planar, apart from the H atoms of the methyl group, as shown by the leading torsion angles (Table 3): in (II) and (III) (Figs. 2 and 3), the ester fragment up to and including atom C12 is effectively coplanar with the adjacent aryl ring, but in (III) in particular, the remaining torsion angles indicate a markedly non-planar conformation. The bond distances show no unusual values, but in each compound the internal angles at atoms C3 and C5, ipso to the nitro groups, are significantly larger than the corresponding angle at C2, ipso to the ester group.

There are no direction-specific intermolecular interactions in the structure of (II), but the molecules of (I) are linked into simple C(7) chains by a single C—H···O hydrogen bond (Table 1). Atom C4 in the molecule at (x, y, z) acts as a hydrogen-bond donor to carbonyl atom O1 in the molecule at (3/2 + x, 3/2 - y, 1/2 + z), so forming a C(7) (Bernstein et al., 1995) chain running parallel to the [301] direction and generated by the n-glide plane at y = 3/4 (Fig. 4). Two such chains, related to one another by inversion, pass through each unit cell, but there are no direction-specific interactions between adjacent chains; in particular, C—H···π(arene) hydrogen bonds and aromatic π–π stacking interactions are both absent. The shortest ring-centroid separation, which involves the molecules at (x, y, z) and (1/2 + x, 3/2 - y, 1/2 + z), is 5.670 (2) Å, and is clearly too large for effective π–π stacking.

The molecules of (III) are linked by four independent C—H···O hydrogen bonds (Table 2) into a three-dimensional framework of considerable complexity. However, it is possible to identify several simple substructures, each generated by a limited number of hydrogen bonds. The formation of the framework is most simply analysed in terms of one finite zero-dimensional motif, which can be regarded as the basic building block; this motif is formed by the concerted action of two of the hydrogen bonds and of two independent chain motifs, each containing a single hydrogen bond, one of which generates a double helix while the other generates a sextuple helix.

In the first substructure, atoms C6 and C12 in the molecule at (x, y, z) act as hydrogen-bond donors, respectively, to atoms O1 and O52 in the molecule at (1 - x, 1 - y, -z) so generating a centrosymmetric dimer centred at (1/2, 1/2, 0), in which inversion-related pairs of hydrogen bonds generate R22(10) and R22(18) rings (Fig. 5). In the second substructure, this time one-dimensional as opposed to zero-dimensional, atom C2 in the molecule at (x, y, z) acts as a hydrogen-bond donor to atom O32 in the molecule at (1 - y, -1/2 + x, 1/2 + z), while atom C2 at (1 - y, -1/2 + x, 1/2 + z) in turn acts as a donor to atom O32 at (3/2 - x, 1/2 - y, 1 + z). Propagation of this hydrogen bond thus generates a C(5) helical chain running parallel to the [001] direction and generated by the 42 screw axis along (3/4, 1/4, z) (Fig. 6). Because the screw axis is of 42 type, this chain links the molecules at (x, y, z) and at (x, y, 2 + z), so that complete definition of this substructure requires two coaxial helices offset by a unit translation along [001].

The combination of this helical chain (Fig. 6) with the centrosymmetric dimer motif (Fig. 5) then links each helical chain to four adjacent helical chains; for example, the helix along (3/4, 1/4, z) is directly linked in this way to those along (1/4, 3/4, z), (5/4, 3/4, z), (1/4, -1/4, z) and (5/4, -1/4, z), so forming a continuous three-dimensional framework. Because of the double-helical nature of the [001] chain, there are in fact two such frameworks, intimately interwoven.

In addition, there is a fourth C—H···O hydrogen bond, whose action in isolation is to generate a sextuple helix of C(11) chains (Fig. 7), but which in combination with the first chain-forming hydrogen bond links the two interwoven frameworks into a single continuous structure. Atom C22 in the molecule at (x, y, z) acts as a hydrogen-bond donor to atom O51 in the molecule at (1 - y, -1/2 + x, 3/2 + z), and atom C22 at (1 - y, -1/2 + x, 3/2 + z) likewise acts as a donor to atom O51 at (3/2 - x, 1/2 - y, 3 + z), and thence via (1/2 + y, 1 - x, 9/2 + z) to (x, y, 6 + z), so generating the sextuple helix. At the same time, atom C2 in the molecule at (1 - y, -1/2 + x, 3/2 + z) acts as a hydrogen-bond donor to atom O32 in the molecule at (3/2 - x, 1/2 - y, 2 + z), thereby linking the two coaxial C(5) helices along (3/4, 1/4, z), and hence linking the two frameworks.

Experimental top

Samples of compounds (I)–(III) were prepared from 3,5-dinitrobenzoic acid using a published procedure (Vogel, 1977). The compounds had the expected NMR and IR spectra, and the melting points were in agreement with those reported (Vogel, 1977). Crystals suitable for single-crystal X-ray diffraction were grown by slow evaporation of solutions in ethanol.

Refinement top

For each of compounds (I) and (II), the space group P21/n was uniquely assigned from the systematic absences. For compound (III), the space group P42/n was uniquely assigned from the systematic absences, and the setting adopted had the origin coincident with a centre of inversion. All H atoms were located in difference maps and then treated as riding atoms, with C—H distances of 0.95 (aromatic), 0.98 Å (methyl), 0.99 Å (CH2) or 1.00 Å (aliphatic CH), and with Uiso(H) values of 1.2Ueq(C), or 1.5Ueq(C) for the methyl groups.

Structure description top

We report here the structures of methyl, isopropyl and benzyl 3,5-dinitrobenzoate, (I)–(III), respectively, derived from low-temperature diffraction data. It has been recognized since the early days of experimental organic chemistry that the 3,5-nitrobenzoate esters of simple alcohols are crystalline solids that are very readily purified and crystallized, and indeed, these crystalline esters were for many decades utilized as an aid to identification of such alcohols by means of their sharp and characteristic melting temperatures. The structures of a few of these esters have been the subject of isolated reports, including the ethyl ester (Hughes & Trotter, 1971) and the 2,2-dimethylbutyl ester, where Z' = 2 (Sax et al., 1976); both of these structure determinations were based on the use of diffraction data collected at ambient temperature. More recently, the structures of the methyl ester (I) (Jin & Xiao, 2000b), the n-propyl ester, where Z' = 2 (Jin & Xiao, 2005c), and the iso-propyl ester, (II) (Jin & Xiao, 2005a), have been reported, also using diffraction data collected at ambient temperature. The structure of the methyl ester (I) was reported to contain π-stacked molecules related by translation along [100] with intermolecular C···C contacts as short as 3.440 (4) Å, despite the a repeat vector of 4.5833 (15) Å; no hydrogen bonds were reported in this compound. Although the unit-cell dimensions, the space group and the atomic coordinates for (I) indicate that no phase change has occurred between ambient temperature and 120 K, we find no π–π stacking in (I), but that nearly linear C—H···O hydrogen bond is present, in contrast to the findings reported previously (Jin & Xiao, 2005b).

The molecule of (I) (Fig. 1) is effectively planar, apart from the H atoms of the methyl group, as shown by the leading torsion angles (Table 3): in (II) and (III) (Figs. 2 and 3), the ester fragment up to and including atom C12 is effectively coplanar with the adjacent aryl ring, but in (III) in particular, the remaining torsion angles indicate a markedly non-planar conformation. The bond distances show no unusual values, but in each compound the internal angles at atoms C3 and C5, ipso to the nitro groups, are significantly larger than the corresponding angle at C2, ipso to the ester group.

There are no direction-specific intermolecular interactions in the structure of (II), but the molecules of (I) are linked into simple C(7) chains by a single C—H···O hydrogen bond (Table 1). Atom C4 in the molecule at (x, y, z) acts as a hydrogen-bond donor to carbonyl atom O1 in the molecule at (3/2 + x, 3/2 - y, 1/2 + z), so forming a C(7) (Bernstein et al., 1995) chain running parallel to the [301] direction and generated by the n-glide plane at y = 3/4 (Fig. 4). Two such chains, related to one another by inversion, pass through each unit cell, but there are no direction-specific interactions between adjacent chains; in particular, C—H···π(arene) hydrogen bonds and aromatic π–π stacking interactions are both absent. The shortest ring-centroid separation, which involves the molecules at (x, y, z) and (1/2 + x, 3/2 - y, 1/2 + z), is 5.670 (2) Å, and is clearly too large for effective π–π stacking.

The molecules of (III) are linked by four independent C—H···O hydrogen bonds (Table 2) into a three-dimensional framework of considerable complexity. However, it is possible to identify several simple substructures, each generated by a limited number of hydrogen bonds. The formation of the framework is most simply analysed in terms of one finite zero-dimensional motif, which can be regarded as the basic building block; this motif is formed by the concerted action of two of the hydrogen bonds and of two independent chain motifs, each containing a single hydrogen bond, one of which generates a double helix while the other generates a sextuple helix.

In the first substructure, atoms C6 and C12 in the molecule at (x, y, z) act as hydrogen-bond donors, respectively, to atoms O1 and O52 in the molecule at (1 - x, 1 - y, -z) so generating a centrosymmetric dimer centred at (1/2, 1/2, 0), in which inversion-related pairs of hydrogen bonds generate R22(10) and R22(18) rings (Fig. 5). In the second substructure, this time one-dimensional as opposed to zero-dimensional, atom C2 in the molecule at (x, y, z) acts as a hydrogen-bond donor to atom O32 in the molecule at (1 - y, -1/2 + x, 1/2 + z), while atom C2 at (1 - y, -1/2 + x, 1/2 + z) in turn acts as a donor to atom O32 at (3/2 - x, 1/2 - y, 1 + z). Propagation of this hydrogen bond thus generates a C(5) helical chain running parallel to the [001] direction and generated by the 42 screw axis along (3/4, 1/4, z) (Fig. 6). Because the screw axis is of 42 type, this chain links the molecules at (x, y, z) and at (x, y, 2 + z), so that complete definition of this substructure requires two coaxial helices offset by a unit translation along [001].

The combination of this helical chain (Fig. 6) with the centrosymmetric dimer motif (Fig. 5) then links each helical chain to four adjacent helical chains; for example, the helix along (3/4, 1/4, z) is directly linked in this way to those along (1/4, 3/4, z), (5/4, 3/4, z), (1/4, -1/4, z) and (5/4, -1/4, z), so forming a continuous three-dimensional framework. Because of the double-helical nature of the [001] chain, there are in fact two such frameworks, intimately interwoven.

In addition, there is a fourth C—H···O hydrogen bond, whose action in isolation is to generate a sextuple helix of C(11) chains (Fig. 7), but which in combination with the first chain-forming hydrogen bond links the two interwoven frameworks into a single continuous structure. Atom C22 in the molecule at (x, y, z) acts as a hydrogen-bond donor to atom O51 in the molecule at (1 - y, -1/2 + x, 3/2 + z), and atom C22 at (1 - y, -1/2 + x, 3/2 + z) likewise acts as a donor to atom O51 at (3/2 - x, 1/2 - y, 3 + z), and thence via (1/2 + y, 1 - x, 9/2 + z) to (x, y, 6 + z), so generating the sextuple helix. At the same time, atom C2 in the molecule at (1 - y, -1/2 + x, 3/2 + z) acts as a hydrogen-bond donor to atom O32 in the molecule at (3/2 - x, 1/2 - y, 2 + z), thereby linking the two coaxial C(5) helices along (3/4, 1/4, z), and hence linking the two frameworks.

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 molecule of (I), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. The molecule of (II), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 3] Fig. 3. The molecule of (III), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 4] Fig. 4. Part of the crystal structure of (I), showing the formation of a C(7) chain along [301]. For the sake of clarity, H atoms not involved in the motif shown have been omitted. Atoms marked with an asterisk (*) or a hash (#) are at the symmetry positions (3/2 + x, 3/2 - y, 1/2 + z) and (-3/2 + x, 3/2 - y, -1/2 + z), respectively.
[Figure 5] Fig. 5. Part of the crystal structure of (III), showing the formation of a centrosymmetric dimer. For the sake of clarity, H atoms bonded to C atoms not involved in the motif shown have been omitted. The atoms marked with an asterisk (*) are at the symmetry position (1 - x, 1 - y, - z).
[Figure 6] Fig. 6. A stereoview of part of the crystal structure of (III), showing a hydrogen-bonded helical C(5) chain generated by the 42 screw axis along (3/4, 1/4, z) and forming one strand of a double helix. For the sake of clarity, H atoms not involved in the motif shown have been omitted.
[Figure 7] Fig. 7. A stereoview of part of the crystal structure of (III), showing a hydrogen-bonded helical C(11) chain generated by the 42 screw axis along (3/4, 1/4, z) and forming one strand of a sextuple helix. For the sake of clarity, H atoms not involved in the motif shown have been omitted.
(I) Methyl 3,5-dinitrobenzoate top
Crystal data top
C8H6N2O6F(000) = 464
Mr = 226.15Dx = 1.655 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 2070 reflections
a = 4.5664 (4) Åθ = 2.9–27.6°
b = 18.727 (2) ŵ = 0.15 mm−1
c = 10.8416 (10) ÅT = 120 K
β = 101.787 (6)°Lath, colourless
V = 907.57 (15) Å30.52 × 0.12 × 0.02 mm
Z = 4
Data collection top
Nonius KappaCCD
diffractometer		2070 independent reflections
Radiation source: Bruker-Nonius FR91 rotating anode1319 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.060
Detector resolution: 9.091 pixels mm-1θmax = 27.6°, θmin = 2.9°
φ and ω scansh = −5→5
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		k = −24→24
Tmin = 0.935, Tmax = 0.997l = −14→14
9551 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)] = 0.058Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.174H-atom parameters constrained
S = 1.09 w = 1/[σ2(Fo2) + (0.0823P)2 + 0.2307P]
where P = (Fo2 + 2Fc2)/3
2070 reflections(Δ/σ)max < 0.001
146 parametersΔρmax = 0.25 e Å−3
0 restraintsΔρmin = −0.29 e Å−3
Crystal data top
C8H6N2O6V = 907.57 (15) Å3
Mr = 226.15Z = 4
Monoclinic, P21/nMo Kα radiation
a = 4.5664 (4) ŵ = 0.15 mm−1
b = 18.727 (2) ÅT = 120 K
c = 10.8416 (10) Å0.52 × 0.12 × 0.02 mm
β = 101.787 (6)°
Data collection top
Nonius KappaCCD
diffractometer		2070 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		1319 reflections with I > 2σ(I)
Tmin = 0.935, Tmax = 0.997Rint = 0.060
9551 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0580 restraints
wR(F2) = 0.174H-atom parameters constrained
S = 1.09Δρmax = 0.25 e Å−3
2070 reflectionsΔρmin = −0.29 e Å−3
146 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O1−0.2774 (3)0.67000 (9)0.18351 (15)0.0278 (4)
O11−0.0789 (4)0.56667 (9)0.26896 (16)0.0297 (5)
O310.8123 (5)0.56191 (10)0.58930 (19)0.0462 (6)
O321.0328 (4)0.65946 (10)0.66327 (15)0.0315 (5)
O510.6277 (4)0.88672 (9)0.50125 (17)0.0356 (5)
O520.2069 (4)0.89026 (9)0.36595 (17)0.0343 (5)
N30.8306 (5)0.62668 (11)0.59376 (18)0.0270 (5)
N50.4141 (4)0.85809 (11)0.43276 (18)0.0251 (5)
C10.1600 (5)0.67207 (13)0.3470 (2)0.0214 (5)
C20.3754 (5)0.63231 (13)0.4289 (2)0.0230 (6)
C30.6005 (5)0.66864 (13)0.5090 (2)0.0218 (5)
C40.6224 (5)0.74254 (13)0.5126 (2)0.0224 (5)
C50.4021 (5)0.77944 (13)0.4308 (2)0.0215 (5)
C60.1734 (5)0.74635 (13)0.3480 (2)0.0228 (5)
C11−0.0892 (5)0.63688 (13)0.2566 (2)0.0233 (6)
C12−0.3115 (6)0.52557 (14)0.1862 (2)0.0333 (7)
H20.36730.58160.42950.028*
H40.77990.76640.56810.027*
H60.02770.77370.29260.027*
H12A−0.50820.53980.20080.050*
H12B−0.28030.47450.20420.050*
H12C−0.30200.53480.09820.050*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0261 (9)0.0272 (10)0.0266 (9)0.0019 (7)−0.0030 (8)0.0002 (7)
O110.0302 (10)0.0234 (10)0.0302 (10)−0.0011 (7)−0.0062 (8)0.0004 (7)
O310.0555 (13)0.0244 (11)0.0479 (12)0.0059 (9)−0.0151 (10)0.0002 (9)
O320.0265 (10)0.0376 (11)0.0259 (9)0.0003 (8)−0.0052 (8)0.0009 (8)
O510.0334 (11)0.0275 (10)0.0401 (11)−0.0079 (8)−0.0058 (9)0.0009 (9)
O520.0358 (11)0.0244 (10)0.0378 (10)0.0085 (8)−0.0040 (9)0.0004 (8)
N30.0277 (12)0.0283 (13)0.0224 (10)0.0037 (9)−0.0006 (9)0.0010 (9)
N50.0276 (12)0.0230 (11)0.0253 (10)−0.0014 (9)0.0065 (9)0.0000 (9)
C10.0229 (12)0.0231 (13)0.0184 (11)0.0003 (9)0.0048 (10)0.0009 (9)
C20.0254 (13)0.0236 (13)0.0203 (11)0.0013 (10)0.0056 (10)0.0003 (10)
C30.0196 (12)0.0248 (13)0.0198 (11)0.0039 (10)0.0012 (10)0.0028 (10)
C40.0197 (12)0.0278 (14)0.0198 (12)−0.0015 (10)0.0039 (9)−0.0022 (10)
C60.0229 (12)0.0258 (13)0.0196 (11)0.0029 (10)0.0041 (10)0.0016 (10)
C50.0236 (13)0.0200 (13)0.0213 (12)0.0005 (10)0.0053 (10)0.0000 (10)
C110.0247 (13)0.0260 (13)0.0197 (11)0.0024 (10)0.0057 (10)0.0000 (10)
C120.0353 (16)0.0242 (14)0.0346 (15)−0.0042 (11)−0.0065 (12)−0.0022 (11)
Geometric parameters (Å, º) top
C1—C61.392 (3)C3—C41.387 (3)
C1—C21.398 (3)C3—N31.474 (3)
C1—C111.495 (3)N3—O311.216 (3)
C11—O11.214 (3)N3—O321.230 (2)
C11—O111.322 (3)C4—C51.383 (3)
O11—C121.462 (3)C4—H40.95
C12—H12A0.98C6—C51.378 (3)
C12—H12B0.98C6—H60.95
C12—H12C0.98C5—N51.474 (3)
C2—C31.381 (3)N5—O511.223 (2)
C2—H20.95N5—O521.226 (2)
C6—C1—C2120.2 (2)C2—C3—N3118.3 (2)
C6—C1—C11118.2 (2)C4—C3—N3118.4 (2)
C2—C1—C11121.6 (2)O31—N3—O32124.0 (2)
O1—C11—O11125.5 (2)O31—N3—C3118.2 (2)
O1—C11—C1123.1 (2)O32—N3—C3117.8 (2)
O11—C11—C1111.44 (19)C5—C4—C3116.2 (2)
C11—O11—C12117.08 (18)C5—C4—H4121.9
O11—C12—H12A109.5C3—C4—H4121.9
O11—C12—H12B109.5C5—C6—C1118.7 (2)
H12A—C12—H12B109.5C5—C6—H6120.6
O11—C12—H12C109.5C1—C6—H6120.6
H12A—C12—H12C109.5C4—C5—C6123.3 (2)
H12B—C12—H12C109.5C6—C5—N5118.7 (2)
C3—C2—C1118.3 (2)C4—C5—N5118.1 (2)
C3—C2—H2120.9O51—N5—O52124.5 (2)
C1—C2—H2120.9O51—N5—C5118.01 (19)
C2—C3—C4123.3 (2)O52—N5—C5117.45 (19)
C6—C1—C11—O10.8 (3)C4—C3—N3—O32−0.5 (3)
C2—C1—C11—O1−179.2 (2)C2—C3—C4—C50.4 (3)
C6—C1—C11—O11−178.01 (19)N3—C3—C4—C5179.70 (18)
C2—C1—C11—O112.0 (3)C2—C1—C6—C50.0 (3)
O1—C11—O11—C121.0 (3)C11—C1—C6—C5−179.97 (19)
C1—C11—O11—C12179.74 (19)C1—C6—C5—C40.8 (3)
C6—C1—C2—C3−0.6 (3)C1—C6—C5—N5−179.33 (19)
C11—C1—C2—C3179.4 (2)C3—C4—C5—C6−1.0 (3)
C1—C2—C3—C40.4 (3)C3—C4—C5—N5179.16 (19)
C1—C2—C3—N3−178.96 (19)C6—C5—N5—O51−175.71 (19)
C2—C3—N3—O310.2 (3)C4—C5—N5—O514.2 (3)
C4—C3—N3—O31−179.2 (2)C6—C5—N5—O524.8 (3)
C2—C3—N3—O32178.86 (19)C4—C5—N5—O52−175.29 (19)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C4—H4···O1i0.952.463.399 (3)171
Symmetry code: (i) x+3/2, −y+3/2, z+1/2.
(II) Isopropyl 3,5-dinitrobenzoate top
Crystal data top
C10H10N2O6F(000) = 528
Mr = 254.20Dx = 1.494 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 2596 reflections
a = 9.7037 (3) Åθ = 3.8–27.5°
b = 5.7152 (2) ŵ = 0.13 mm−1
c = 20.4739 (9) ÅT = 120 K
β = 95.504 (2)°Block, colourless
V = 1130.22 (7) Å30.42 × 0.40 × 0.38 mm
Z = 4
Data collection top
Nonius KappaCCD
diffractometer		2596 independent reflections
Radiation source: Bruker-Nonius FR91 rotating anode2045 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.031
Detector resolution: 9.091 pixels mm-1θmax = 27.5°, θmin = 3.8°
φ and ω scansh = −12→12
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		k = −7→7
Tmin = 0.944, Tmax = 0.954l = −24→26
10022 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) = 0.105H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0561P)2 + 0.2191P]
where P = (Fo2 + 2Fc2)/3
2596 reflections(Δ/σ)max = 0.001
165 parametersΔρmax = 0.30 e Å−3
0 restraintsΔρmin = −0.34 e Å−3
Crystal data top
C10H10N2O6V = 1130.22 (7) Å3
Mr = 254.20Z = 4
Monoclinic, P21/nMo Kα radiation
a = 9.7037 (3) ŵ = 0.13 mm−1
b = 5.7152 (2) ÅT = 120 K
c = 20.4739 (9) Å0.42 × 0.40 × 0.38 mm
β = 95.504 (2)°
Data collection top
Nonius KappaCCD
diffractometer		2596 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		2045 reflections with I > 2σ(I)
Tmin = 0.944, Tmax = 0.954Rint = 0.031
10022 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0390 restraints
wR(F2) = 0.105H-atom parameters constrained
S = 1.05Δρmax = 0.30 e Å−3
2596 reflectionsΔρmin = −0.34 e Å−3
165 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.27425 (9)0.16199 (16)0.63304 (5)0.0258 (2)
O110.32924 (8)0.47435 (15)0.57331 (4)0.0207 (2)
O310.63611 (10)1.06799 (16)0.67549 (5)0.0288 (2)
O320.67594 (9)1.08403 (16)0.78148 (5)0.0261 (2)
O510.52347 (10)0.45491 (17)0.91396 (5)0.0314 (3)
O520.41232 (9)0.16298 (16)0.86658 (5)0.0288 (2)
N30.62359 (10)0.99248 (18)0.73064 (6)0.0208 (2)
N50.46624 (10)0.35684 (19)0.86574 (5)0.0217 (3)
C10.39856 (12)0.4773 (2)0.68655 (6)0.0178 (3)
C20.47145 (11)0.6845 (2)0.68063 (6)0.0184 (3)
C30.54042 (11)0.7796 (2)0.73684 (6)0.0180 (3)
C40.53871 (11)0.6808 (2)0.79833 (6)0.0192 (3)
C50.46452 (12)0.4756 (2)0.80192 (6)0.0182 (3)
C60.39433 (11)0.3724 (2)0.74748 (6)0.0183 (3)
C110.32647 (11)0.3529 (2)0.62836 (6)0.0184 (3)
C120.25439 (13)0.3717 (2)0.51385 (6)0.0240 (3)
C130.21072 (19)0.5760 (3)0.47026 (8)0.0435 (4)
C140.35003 (15)0.2029 (3)0.48437 (8)0.0357 (4)
H20.47390.75880.63920.022*
H40.58610.75040.83620.023*
H60.34390.23160.75170.022*
H120.17050.28650.52600.029*
H13A0.15840.68760.49460.065*
H13B0.15230.52030.43170.065*
H13C0.29300.65330.45610.065*
H14A0.43420.28520.47450.053*
H14B0.30360.13740.44380.053*
H14C0.37460.07620.51560.053*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0150 (5)0.0180 (6)0.0205 (7)0.0023 (5)0.0023 (5)−0.0018 (5)
C20.0164 (5)0.0184 (6)0.0211 (6)0.0023 (5)0.0045 (5)0.0007 (5)
C30.0145 (5)0.0142 (6)0.0257 (7)0.0004 (5)0.0042 (5)−0.0016 (5)
N30.0171 (5)0.0175 (5)0.0283 (6)−0.0001 (4)0.0043 (4)−0.0031 (4)
O310.0308 (5)0.0251 (5)0.0311 (6)−0.0060 (4)0.0072 (4)0.0035 (4)
O320.0231 (4)0.0227 (5)0.0325 (6)−0.0042 (4)0.0028 (4)−0.0069 (4)
C40.0153 (5)0.0197 (6)0.0225 (7)0.0017 (5)0.0015 (5)−0.0039 (5)
C50.0160 (5)0.0191 (6)0.0197 (7)0.0035 (5)0.0031 (4)0.0008 (5)
N50.0179 (5)0.0251 (6)0.0219 (6)0.0005 (4)0.0007 (4)0.0020 (5)
O510.0359 (5)0.0350 (6)0.0216 (5)−0.0047 (4)−0.0061 (4)0.0003 (4)
O520.0301 (5)0.0267 (5)0.0296 (6)−0.0074 (4)0.0029 (4)0.0062 (4)
C60.0142 (5)0.0165 (6)0.0247 (7)0.0008 (5)0.0038 (5)0.0002 (5)
C110.0147 (5)0.0192 (6)0.0214 (7)0.0002 (5)0.0026 (5)−0.0004 (5)
O10.0279 (5)0.0233 (5)0.0257 (5)−0.0080 (4)0.0008 (4)0.0003 (4)
O110.0235 (4)0.0212 (5)0.0170 (5)−0.0038 (4)0.0001 (3)−0.0005 (3)
C120.0267 (6)0.0248 (7)0.0193 (7)−0.0063 (5)−0.0032 (5)−0.0014 (5)
C130.0634 (11)0.0327 (8)0.0302 (9)−0.0079 (8)−0.0173 (8)0.0055 (7)
C140.0374 (8)0.0390 (8)0.0313 (8)−0.0078 (7)0.0065 (6)−0.0141 (7)
Geometric parameters (Å, º) top
C1—C61.3883 (17)N5—O521.2261 (14)
C1—C21.3907 (17)C6—H60.95
C1—C111.5014 (17)C11—O11.2109 (15)
C2—C31.3856 (17)C11—O111.3260 (15)
C2—H20.95O11—C121.4778 (15)
C3—C41.3813 (17)C12—C141.505 (2)
C3—N31.4721 (16)C12—C131.5058 (19)
N3—O311.2257 (14)C12—H121.00
N3—O321.2303 (14)C13—H13A0.98
C4—C51.3819 (17)C13—H13B0.98
C4—H40.95C13—H13C0.98
C5—C61.3815 (17)C14—H14A0.98
C5—N51.4710 (16)C14—H14B0.98
N5—O511.2216 (14)C14—H14C0.98
C6—C1—C2120.34 (11)C1—C6—H6120.5
C6—C1—C11117.19 (11)O1—C11—O11125.56 (11)
C2—C1—C11122.43 (11)O1—C11—C1122.05 (11)
C3—C2—C1118.09 (12)O11—C11—C1112.38 (10)
C3—C2—H2121.0C11—O11—C12116.36 (10)
C1—C2—H2121.0O11—C12—C14108.16 (11)
C4—C3—C2123.34 (11)O11—C12—C13105.57 (11)
C4—C3—N3118.10 (11)C14—C12—C13114.13 (13)
C2—C3—N3118.53 (11)O11—C12—H12109.6
O31—N3—O32124.07 (11)C14—C12—H12109.6
O31—N3—C3118.30 (10)C13—C12—H12109.6
O32—N3—C3117.63 (11)C12—C13—H13A109.5
C3—C4—C5116.57 (11)C12—C13—H13B109.5
C3—C4—H4121.7H13A—C13—H13B109.5
C5—C4—H4121.7C12—C13—H13C109.5
C6—C5—C4122.58 (12)H13A—C13—H13C109.5
C6—C5—N5118.84 (11)H13B—C13—H13C109.5
C4—C5—N5118.51 (11)C12—C14—H14A109.5
O51—N5—O52124.39 (11)C12—C14—H14B109.5
O51—N5—C5118.15 (11)H14A—C14—H14B109.5
O52—N5—C5117.45 (10)C12—C14—H14C109.5
C5—C6—C1119.07 (12)H14A—C14—H14C109.5
C5—C6—H6120.5H14B—C14—H14C109.5
C6—C1—C2—C30.88 (17)C6—C5—N5—O524.66 (16)
C11—C1—C2—C3−176.74 (10)C4—C5—N5—O52−172.37 (11)
C1—C2—C3—C4−0.94 (17)C4—C5—C6—C10.32 (18)
C1—C2—C3—N3176.99 (10)N5—C5—C6—C1−176.58 (10)
C4—C3—N3—O31173.16 (10)C2—C1—C6—C5−0.59 (17)
C2—C3—N3—O31−4.88 (16)C11—C1—C6—C5177.15 (10)
C4—C3—N3—O32−7.08 (15)C6—C1—C11—O1−4.72 (17)
C2—C3—N3—O32174.88 (10)C2—C1—C11—O1172.98 (11)
C2—C3—C4—C50.67 (17)C6—C1—C11—O11176.07 (10)
N3—C3—C4—C5−177.27 (10)C2—C1—C11—O11−6.24 (16)
C3—C4—C5—C6−0.34 (17)O1—C11—O11—C123.94 (17)
C3—C4—C5—N5176.57 (10)C1—C11—O11—C12−176.88 (9)
C6—C5—N5—O51−176.84 (11)C11—O11—C12—C14−85.33 (13)
C4—C5—N5—O516.13 (16)C11—O11—C12—C13152.12 (12)
(III) Benzyl 3,5-dinitrobenzoate? top
Crystal data top
C14H10N2O6Dx = 1.529 Mg m−3
Mr = 302.24Mo Kα radiation, λ = 0.71073 Å
Tetragonal, P42/nCell parameters from 3000 reflections
Hall symbol: -P 4bcθ = 3.1–27.5°
a = 20.8531 (5) ŵ = 0.12 mm−1
c = 6.0377 (2) ÅT = 120 K
V = 2625.50 (12) Å3Needle, colourless
Z = 80.22 × 0.06 × 0.04 mm
F(000) = 1248
Data collection top
Nonius KappaCCD
diffractometer		3000 independent reflections
Radiation source: Bruker-Nonius FR91 rotating anode2413 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.053
Detector resolution: 9.091 pixels mm-1θmax = 27.5°, θmin = 3.1°
φ and ω scansh = −27→26
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		k = −16→27
Tmin = 0.978, Tmax = 0.995l = −7→7
18873 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) = 0.103H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0355P)2 + 1.5651P]
where P = (Fo2 + 2Fc2)/3
3000 reflections(Δ/σ)max = 0.001
199 parametersΔρmax = 0.24 e Å−3
0 restraintsΔρmin = −0.23 e Å−3
Crystal data top
C14H10N2O6Z = 8
Mr = 302.24Mo Kα radiation
Tetragonal, P42/nµ = 0.12 mm−1
a = 20.8531 (5) ÅT = 120 K
c = 6.0377 (2) Å0.22 × 0.06 × 0.04 mm
V = 2625.50 (12) Å3
Data collection top
Nonius KappaCCD
diffractometer		3000 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		2413 reflections with I > 2σ(I)
Tmin = 0.978, Tmax = 0.995Rint = 0.053
18873 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0430 restraints
wR(F2) = 0.103H-atom parameters constrained
S = 1.05Δρmax = 0.24 e Å−3
3000 reflectionsΔρmin = −0.23 e Å−3
199 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.49125 (5)0.44104 (6)0.1932 (2)0.0254 (3)
O110.52732 (5)0.40805 (5)0.52649 (18)0.0211 (3)
O310.74509 (6)0.32867 (7)0.5879 (2)0.0376 (3)
O320.81810 (5)0.37069 (6)0.3788 (2)0.0284 (3)
O510.75704 (5)0.47883 (6)−0.2874 (2)0.0273 (3)
O520.66120 (6)0.51811 (6)−0.3183 (2)0.0287 (3)
N30.76221 (6)0.36163 (7)0.4312 (2)0.0226 (3)
N50.70199 (6)0.48641 (6)−0.2208 (2)0.0206 (3)
C10.60325 (7)0.42401 (7)0.2460 (3)0.0172 (3)
C20.64954 (7)0.39295 (7)0.3724 (3)0.0181 (3)
C30.71241 (7)0.39371 (7)0.2979 (3)0.0188 (3)
C40.73094 (7)0.42425 (7)0.1063 (3)0.0185 (3)
C50.68335 (7)0.45441 (7)−0.0135 (3)0.0175 (3)
C60.61973 (7)0.45520 (7)0.0503 (3)0.0180 (3)
C110.53428 (7)0.42524 (7)0.3149 (3)0.0181 (3)
C120.46199 (7)0.41048 (8)0.6171 (3)0.0209 (3)
C210.42942 (7)0.34636 (7)0.5979 (3)0.0192 (3)
C220.43489 (8)0.30202 (8)0.7690 (3)0.0242 (4)
C230.40476 (9)0.24289 (9)0.7537 (3)0.0296 (4)
C240.36916 (8)0.22777 (8)0.5671 (3)0.0293 (4)
C250.36404 (8)0.27124 (8)0.3950 (3)0.0270 (4)
C260.39397 (8)0.33054 (8)0.4104 (3)0.0219 (4)
H20.63840.37180.50630.022*
H40.77440.42460.05880.022*
H60.58820.4764−0.03670.022*
H12A0.43670.44310.53590.025*
H12B0.46380.42340.77480.025*
H220.45940.31230.89680.029*
H230.40850.21280.87110.036*
H240.34820.18740.55730.035*
H250.34010.26050.26640.032*
H260.39020.36040.29240.026*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0169 (7)0.0146 (7)0.0201 (8)−0.0015 (6)−0.0002 (6)−0.0025 (6)
C20.0196 (8)0.0159 (7)0.0187 (8)−0.0025 (6)−0.0007 (6)−0.0005 (6)
C30.0183 (8)0.0171 (8)0.0210 (8)0.0011 (6)−0.0031 (6)−0.0015 (6)
N30.0191 (7)0.0253 (7)0.0235 (7)0.0027 (5)−0.0016 (6)0.0009 (6)
O320.0155 (6)0.0409 (7)0.0287 (7)0.0048 (5)−0.0011 (5)0.0001 (6)
O310.0285 (7)0.0473 (8)0.0369 (8)0.0044 (6)−0.0004 (6)0.0228 (7)
C40.0164 (7)0.0173 (8)0.0218 (8)−0.0009 (6)0.0004 (6)−0.0026 (6)
C50.0207 (8)0.0137 (7)0.0182 (8)−0.0025 (6)0.0013 (6)−0.0013 (6)
N50.0222 (7)0.0188 (7)0.0206 (7)−0.0022 (5)0.0009 (6)0.0004 (6)
O520.0285 (7)0.0305 (7)0.0271 (7)0.0026 (5)−0.0010 (5)0.0108 (5)
O510.0220 (6)0.0325 (7)0.0275 (7)−0.0003 (5)0.0074 (5)0.0030 (5)
C60.0185 (8)0.0151 (7)0.0206 (8)−0.0009 (6)−0.0025 (6)−0.0013 (6)
C110.0187 (8)0.0152 (7)0.0204 (8)−0.0015 (6)−0.0013 (6)0.0012 (6)
O10.0184 (6)0.0317 (7)0.0261 (6)0.0013 (5)−0.0020 (5)0.0065 (5)
O110.0150 (5)0.0283 (6)0.0199 (6)−0.0014 (4)0.0014 (5)0.0028 (5)
C120.0160 (8)0.0260 (8)0.0207 (8)0.0001 (6)0.0035 (6)−0.0016 (7)
C210.0147 (7)0.0211 (8)0.0218 (8)0.0026 (6)0.0037 (6)0.0004 (6)
C220.0210 (8)0.0288 (9)0.0229 (9)0.0031 (7)0.0005 (7)0.0040 (7)
C230.0294 (10)0.0261 (9)0.0334 (10)0.0044 (7)0.0049 (8)0.0102 (8)
C240.0271 (9)0.0192 (8)0.0414 (11)−0.0025 (7)0.0035 (8)0.0006 (8)
C250.0250 (9)0.0243 (9)0.0318 (10)−0.0023 (7)−0.0032 (7)−0.0018 (7)
C260.0201 (8)0.0227 (8)0.0230 (9)0.0017 (6)−0.0011 (7)0.0031 (7)
Geometric parameters (Å, º) top
C1—C21.391 (2)C11—O111.3350 (19)
C1—C61.392 (2)O11—C121.4690 (18)
C1—C111.497 (2)C12—C211.504 (2)
C2—C31.386 (2)C12—H12A0.99
C2—H20.95C12—H12B0.99
C3—C41.376 (2)C21—C221.391 (2)
C3—N31.474 (2)C21—C261.392 (2)
N3—O321.2223 (17)C22—C231.387 (2)
N3—O311.2224 (18)C22—H220.95
C4—C51.380 (2)C23—C241.386 (3)
C4—H40.95C23—H230.95
C5—C61.381 (2)C24—C251.383 (3)
C5—N51.471 (2)C24—H240.95
N5—O511.2263 (17)C25—C261.388 (2)
N5—O521.2275 (17)C25—H250.95
C6—H60.95C26—H260.95
C11—O11.2053 (19)
C2—C1—C6120.82 (14)O11—C11—C1111.45 (13)
C2—C1—C11121.48 (14)C11—O11—C12116.61 (12)
C6—C1—C11117.70 (14)O11—C12—C21111.06 (12)
C3—C2—C1118.23 (15)O11—C12—H12A109.4
C3—C2—H2120.9C21—C12—H12A109.4
C1—C2—H2120.9O11—C12—H12B109.4
C4—C3—C2122.94 (15)C21—C12—H12B109.4
C4—C3—N3118.11 (14)H12A—C12—H12B108.0
C2—C3—N3118.93 (14)C22—C21—C26119.35 (15)
O32—N3—O31124.45 (14)C22—C21—C12119.77 (15)
O32—N3—C3117.39 (13)C26—C21—C12120.88 (14)
O31—N3—C3118.15 (13)C23—C22—C21120.28 (16)
C3—C4—C5116.73 (14)C23—C22—H22119.9
C3—C4—H4121.6C21—C22—H22119.9
C5—C4—H4121.6C24—C23—C22119.95 (16)
C4—C5—C6123.37 (15)C24—C23—H23120.0
C4—C5—N5117.57 (14)C22—C23—H23120.0
C6—C5—N5119.06 (14)C25—C24—C23120.20 (16)
O51—N5—O52124.14 (14)C25—C24—H24119.9
O51—N5—C5117.88 (13)C23—C24—H24119.9
O52—N5—C5117.96 (13)C24—C25—C26119.93 (17)
C5—C6—C1117.92 (14)C24—C25—H25120.0
C5—C6—H6121.0C26—C25—H25120.0
C1—C6—H6121.0C25—C26—C21120.29 (16)
O1—C11—O11125.14 (15)C25—C26—H26119.9
O1—C11—C1123.40 (15)C21—C26—H26119.9
C6—C1—C2—C3−0.2 (2)C11—C1—C6—C5179.75 (13)
C11—C1—C2—C3179.86 (14)C2—C1—C11—O1−166.04 (15)
C1—C2—C3—C40.6 (2)C6—C1—C11—O114.0 (2)
C1—C2—C3—N3179.32 (13)C2—C1—C11—O1115.2 (2)
C4—C3—N3—O328.9 (2)C6—C1—C11—O11−164.72 (13)
C2—C3—N3—O32−169.88 (14)O1—C11—O11—C12−1.7 (2)
C4—C3—N3—O31−172.16 (15)C1—C11—O11—C12177.03 (12)
C2—C3—N3—O319.1 (2)C11—O11—C12—C2193.65 (16)
C2—C3—C4—C5−0.6 (2)O11—C12—C21—C2289.93 (17)
N3—C3—C4—C5−179.32 (13)O11—C12—C21—C26−89.78 (17)
C3—C4—C5—C60.2 (2)C26—C21—C22—C23−0.7 (2)
C3—C4—C5—N5−178.99 (13)C12—C21—C22—C23179.61 (15)
C4—C5—N5—O517.5 (2)C21—C22—C23—C240.2 (3)
C6—C5—N5—O51−171.70 (14)C22—C23—C24—C250.6 (3)
C4—C5—N5—O52−173.68 (14)C23—C24—C25—C26−0.8 (3)
C6—C5—N5—O527.1 (2)C24—C25—C26—C210.3 (3)
C4—C5—C6—C10.2 (2)C22—C21—C26—C250.4 (2)
N5—C5—C6—C1179.36 (13)C12—C21—C26—C25−179.86 (15)
C2—C1—C6—C5−0.2 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2···O32i0.952.523.460 (2)170
C6—H6···O1ii0.952.573.493 (2)164
C12—H12A···O52ii0.992.563.474 (2)154
C22—H22···O51iii0.952.573.360 (2)140
Symmetry codes: (i) −y+1, x−1/2, z+1/2; (ii) −x+1, −y+1, −z; (iii) −y+1, x−1/2, z+3/2.

Experimental details

(I)(II)(III)
Crystal data
Chemical formulaC8H6N2O6C10H10N2O6C14H10N2O6
Mr226.15254.20302.24
Crystal system, space groupMonoclinic, P21/nMonoclinic, P21/nTetragonal, P42/n
Temperature (K)120120120
a, b, c (Å)4.5664 (4), 18.727 (2), 10.8416 (10)9.7037 (3), 5.7152 (2), 20.4739 (9)20.8531 (5), 20.8531 (5), 6.0377 (2)
α, β, γ (°)90, 101.787 (6), 9090, 95.504 (2), 9090, 90, 90
V (Å3)907.57 (15)1130.22 (7)2625.50 (12)
Z448
Radiation typeMo KαMo KαMo Kα
µ (mm−1)0.150.130.12
Crystal size (mm)0.52 × 0.12 × 0.020.42 × 0.40 × 0.380.22 × 0.06 × 0.04
Data collection
DiffractometerNonius KappaCCDNonius KappaCCDNonius KappaCCD
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2003)		Multi-scan
(SADABS; Sheldrick, 2003)		Multi-scan
(SADABS; Sheldrick, 2003)
Tmin, Tmax0.935, 0.9970.944, 0.9540.978, 0.995
No. of measured, independent and
observed [I > 2σ(I)] reflections		9551, 2070, 1319 10022, 2596, 2045 18873, 3000, 2413
Rint0.0600.0310.053
(sin θ/λ)max (Å−1)0.6510.6500.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.058, 0.174, 1.09 0.039, 0.105, 1.05 0.043, 0.103, 1.05
No. of reflections207025963000
No. of parameters146165199
H-atom treatmentH-atom parameters constrainedH-atom parameters constrainedH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.25, −0.290.30, −0.340.24, −0.23

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
C4—H4···O1i0.952.463.399 (3)171
Symmetry code: (i) x+3/2, −y+3/2, z+1/2.
Hydrogen-bond geometry (Å, º) for (III) top
D—H···AD—HH···AD···AD—H···A
C2—H2···O32i0.952.523.460 (2)170
C6—H6···O1ii0.952.573.493 (2)164
C12—H12A···O52ii0.992.563.474 (2)154
C22—H22···O51iii0.952.573.360 (2)140
Symmetry codes: (i) −y+1, x−1/2, z+1/2; (ii) −x+1, −y+1, −z; (iii) −y+1, x−1/2, z+3/2.
Selected bond angles and torsion angles (°) for compounds (I)–(III) top
Parameter(I)(II)(III)
C6-C1-C2120.2 (2)120.34 (11)120.82 (14)
C2-C3-C4123.3 (2)123.34 (11)122.94 (15)
C4-C5-C6123.3 (2)122.58 (12)123.37 (15)
C2-C1-C11-O112.0 (3)-6.24 (16)15.2 (2)
C1-C11-O11-C12179.74 (19)-176.88 (9)177.03 (12)
C11-O11-C12-C13152.12(120
C11-O11-C12-C14-85.33 (13)
C11-O11-C12-C2193.65 (16)
O11-C12-C21-C2289.93 (7)
C2-C3-N3-O310.2 (3)-4.88 (16)9.1 (2)
C4-C5-N5-O514.2 (3)6.13 (16)7.5 (2)
 

Acknowledgements

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

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CHEMISTRY
ISSN: 2053-2296
Volume 62| Part 1| January 2006| Pages o26-o29
doi:10.1107/S0108270105038631
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