Supramolecular structures of three isomeric (E,E)-1-(2-iodo­phenyl)-4-(nitro­phenyl)-2,3-diaza-1,3-butadienes: changes in inter­molecular inter­actions consequent upon changes of substituent location

Glidewell, C.; Low, J.N.; Skakle, J.M.S.; Wardell, J.L.

doi:10.1107/S0108270105009248

organic compounds

STRUCTURAL
CHEMISTRY

ISSN: 2053-2296

Volume 61| Part 5| May 2005| Pages o312-o316

doi:10.1107/S0108270105009248

Supramolecular structures of three isomeric (E,E)-1-(2-iodophenyl)-4-(nitrophenyl)-2,3-diaza-1,3-butadienes: changes in intermolecular interactions consequent upon changes of substituent location

Christopher Glidewell,^a ^* John N. Low,^b Janet M. S. Skakle ^b and James L. Wardell ^c

^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 22 March 2005; accepted 23 March 2005; online 23 April 2005)

The supramolecular structures of the three isomeric (E,E)-1-(2-iodophenyl)-4-(2/3/4-nitrophenyl)-2,3-diaza-1,3-butadienes, C₁₄H₁₀IN₃O₂, are compared. In the 2-nitro isomer, the molecules are disordered across centres of inversion in space group C2/c and are linked into chains by a two-centre iodo–nitro interaction. The molecules of the 3-nitro isomer are linked into a three-dimensional framework by a combination of C—H⋯O and C—H⋯I hydrogen bonds and aromatic π–π stacking interactions, while molecules of the 4-nitro isomer are linked into sheets by a C—H⋯O hydrogen bond and a two-centre iodo–nitro interaction.

Comment

In the course of our continuing investigation of the interplay between hard and soft (Braga et al., 1995 ; Desiraju & Steiner, 1999 ) hydrogen bonds, aromatic π–π stacking interactions and iodo–nitro interactions in simple bis-arene systems, we have studied the supramolecular structures of an extensive series of iodoaryl–nitroaryl compounds, many in several isomeric forms, including examples of sulfonamides (Kelly et al., 2002 ), benzylideneanilines (Glidewell, Howie et al., 2002 ; Wardell et al., 2002 ), benzylanilines (Glidewell, Low et al., 2002 ; Glidewell, Low, Skakle, Wardell & Wardell, 2004 ) benzenesulfanylanilines (Glidewell et al., 2003a ) and phenylhydrazones (Glidewell et al., 2003b ; Glidewell, Low, Skakle & Wardell, 2004 ). We have now extended this study to the isomeric (E,E)-1-(2-iodophenyl)-4-(2/3/4-nitrophenyl)-2,3-diaza-1,3-butadienes, and report here on the molecular and supramolecular structures of three such isomers, containing the 2-nitrophenyl, 3-nitrophenyl, or 4-nitrophenyl substituents, compounds (I)–(III), respectively (Figs. 1–3 ).

The crystallization characteristics of the three isomers (I)–(III) are all different, with (I) crystallizing in C2/c with Z′ = $[{1\over 2}]$ , and a value of Z′ = 1 for each of isomers (II) and (III), in space groups P $[\overline{1}]$ and C2/c, respectively. However, the intramolecular geometries are all fairly similar. The central –CH=N—N=CH– fragment is strictly planar in isomer (I) and approximately so in isomers (II) and (III), and the substituents at each of the C=N bonds adopt E configurations. The independent aryl rings are all twisted slightly away from this plane, to the greatest extent in (I) and the least in (III), as shown by the relevant torsion angles (Tables 1, 2 and 4). In addition, the nitro groups are all rotated away from the planes of the adjacent aryl rings, to the greatest extent in (I) and the least in (II). Corresponding bond lengths and angles are all very similar for the three isomers and there are no unusual values. In isomer (I), the population of the iodo site was found to exceed that of the nitro sites, with occupancy factors of 0.559 (3) and 0.441 (3), respectively. We conclude that some reorganization of substituted aryl groups has occurred, either during the synthesis of (I) or during its crystallization, such that a small proportion of (E,E)-1,4-bis(2-iodophenyl)-2,3-diaza-1,3-butadiene has co-crystallized with (I).

The molecules of compound (I) (Fig. 1) lie across inversion centres in space group C2/c, with the iodo and nitro substituents disordered; the reference molecule was selected as that lying across ( $[{1\over 2}]$ , $[{1\over 2}]$ , $[{1\over 2}]$ ). The paucity of direction-specific intermolecular interactions in (I) is striking: there are no intermolecular hydrogen bonds of any kind and no aromatic π–π stacking interactions are present. However, atom I2 at (x, y, z) can make two possible contacts, with either another I2 or with nitro atom O21, both at (1 − x, y, $[{3\over 2}]$ − z), i.e. both components of the molecule of (I) centred across ( $[{1\over 2}]$ , $[{1\over 2}]$ , 1), and with dimensions I⋯Iⁱ = 3.247 (2) Å and C—I⋯Iⁱ = 163.3 (2)°, and I⋯Oⁱ = 3.312 (8) Å and C—I⋯Oⁱ = 167.1 (2)° [symmetry code: (i) 1 − x, y, $[{3\over 2}]$ − z]. It is convenient to consider first the possible consequences of these interactions in pure (I), and then to consider the effects of the co-crystallized diiodo compound. If adjacent molecules of (I) along [001] are consistently aligned in a head-to-tail fashion, then the iodo–nitro interaction generates a C(11) chain (Starbuck et al., 1999 ) along [001]. If, however, adjacent molecules are aligned in a head-to-head fashion, the I⋯I contact can only link the molecules together in pairs.

The angular properties of this C—I⋯I interaction are admirably consistent with generalizations proposed (Ramasubbu et al., 1986 ) from the results of database analysis, namely that in structures where X⋯X distances (X = halogen) are significantly less than the van der Waals sum, the observed C—X⋯X angles are clustered either around 180° or around 90°. These authors also note that, in such interactions, X⋯X distances are commonly observed ca 0.5 Å below the conventional van der Waals sum of 3.90 Å for I⋯I (Bondi, 1964 ). The short I⋯I contact distance here is well below the van der Waals sum, even allowing for the polar flattening effect (Nyburg & Faerman, 1985 ), and may point to an avoidance of such I⋯I contacts wherever possible. Such avoidance is readily achieved by the head-to-tail alignment of the molecules of (I) within an [001] chain, so that disorder of the molecules is correlated in one direction. This neither implies nor requires any correlation between adjacent [001] chains. Such short contacts can be avoided, even when a molecule of the diiodo analogue is present; such a molecule can readily form two iodo–nitro interactions, one at each I atom. Each such diiodo molecule would, in these circumstances, simply effect a reversal in the polarity of a chain formed by molecules of (I). Overall, therefore, we conclude that molecules of (I) are linked into [001] chains by a two-centre iodo–nitro interaction, with no short I⋯I contacts.

The molecules of compound (II) (Fig. 2) are linked into a three-dimensional framework by a combination of C—H⋯O and C—H⋯I hydrogen bonds and two independent aromatic π–π stacking interactions. The hydrogen bonds together generate a one-dimensional substructure, and each of the stacking interactions in combination with the C—H⋯I hydrogen bonds independently generates a further one-dimensional substructure. Accordingly, the formation of the framework is most readily analysed and discussed in terms of these three simple substructures.

Aryl atom C12 and methine atom C27 in the molecule at (x, y, z) both act as hydrogen-bond donors to iodine I22 in the molecule at (1 − x, 1 − y, 1 − z), thereby generating a centrosymmetric dimer characterized by an array of three edge-fused [R₂¹(9)][R₂²(10)][R₂¹(9)] rings (Bernstein et al., 1995 ), centred at ( $[{1\over 2}]$ , $[{1\over 2}]$ , $[{1\over 2}]$ ) (Fig. 4). These complex dimers are themselves linked by a further hydrogen bond, of the C—H⋯O type: the aryl atom C25 in the molecule at (x, y, z) acts as donor to nitro atom O32 in the molecule at (1 + x, y, 1 + z), so forming a C(13) chain running parallel to the [101] direction. Propagation of this hydrogen bond by translation and inversion then links the dimers into a [101] ribbon, in the form of a chain of edge-fused rings, with R₄⁴(22) rings centred at (n, $[{1\over 2}]$ , n) (n = zero or integer), alternating with R₂²(10) rings centred at ( $[{1\over 2}]$ + n, $[{1\over 2}]$ , $[{1\over 2}]$ + n) (n = zero or integer), with the R₂¹(9) rings on the two edges of the ribbon (Fig. 4).

The dimers generated by the C—H⋯I hydrogen bonds in (II) are also linked by two independent π–π stacking interactions to form two further one-dimensional substructures. The first of these involves the centrosymmetric pair of molecules at (x, y, z) and (−x, −y, 1 − z), which are components of the dimers centred at ( $[{1\over 2}]$ , $[{1\over 2}]$ , $[{1\over 2}]$ ) and (− $[{1\over 2}]$ , − $[{1\over 2}]$ , $[{1\over 2}]$ ), respectively. The nitrated ring at (x, y, z) and the iodinated ring at (−x, −y, 1 − z) are nearly parallel, with a dihedral angle between their planes of only 2.3 (2)°. The interplanar spacing is ca 3.47 Å and the ring-centroid separation is 3.767 (2) Å, corresponding to a near-ideal centroid offset of ca 1.47 Å. Propagation of this interaction by inversion then links the hydrogen-bonded dimers into a π-stacked chain running parallel to the [110] direction (Fig. 5).

The second stacking interaction involves the centrosymmetric pair of molecules at (x, y, z) and (1 − x, −y, 1 − z), components of hydrogen-bonded dimers centred at ( $[{1\over 2}]$ , $[{1\over 2}]$ , $[{1\over 2}]$ ) and ( $[{1\over 2}]$ , − $[{1\over 2}]$ , $[{1\over 2}]$ ). Again, the adjacent ring planes make a dihedral angle of 2.3 (2)°, but now the interplanar spacing is ca 3.42 Å, with a ring-centroid separation of 3.725 (2) Å, giving a ring-centroid offset of ca 1.48 Å. Propagation of this interaction then generates a chain of dimers along [010] (Fig. 6). The combination of the independent chains along [101], [110] and [010] is sufficient to link all of the molecules of (II) into a single three-dimensional framework. It is notable, however, that iodo–nitro interactions are absent from the structure of (II).

The molecules of compound (III) (Fig. 3) are linked into sheets by a combination of a rather weak C—H⋯O hydrogen bond and a two-centre iodo–nitro interaction, and again it is convenient to consider the effect of each of these interactions in turn. Aryl atom C12 in the molecule at (x, y, z) acts as hydrogen-bond donor to nitro atom O42 in the molecule at (x, y − 1, z), so generating by translation a C(6) chain running parallel to the [010] direction (Fig. 7); eight chains of this type pass through each unit cell. In addition, atom I22 in the molecule at (x, y, z) forms a nearly linear two-centre I⋯O interaction with nitro atom O41 in the molecule at ( $[{1\over 2}]$ + x, $[{3\over 2}]$ − y, $[{1\over 2}]$ + z), with dimensions I⋯Oⁱ = 3.362 (2) Å, C—I⋯Oⁱ = 171.62 (6)° and I⋯Oⁱ—Nⁱ = 113.6 (2)° [symmetry code: (i) $[{1\over 2}]$ + x, $[{3\over 2}]$ − y, $[{1\over 2}]$ + z]. In this way, a C(13) (Starbuck et al., 1999) chain is formed running parallel to the [101] direction and generated by the n-glide plane at y = $[{3\over 4}]$ (Fig. 8). The combination of the [010] and [101] chains generates a (10 $[\overline{1}]$ ) sheet in the form of a (4,4)-net built from a single type of R₄⁴(32) ring (Fig. 9). Four sheets of this type pass through each unit cell, but there are no direction-specific interactions between adjacent sheets. In particular, C—H⋯π(arene) hydrogen bonds and aromatic π–π stacking interactions are absent from the structure of (III).

Figure 1
The molecule of compound (I)

, showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level. For the sake of clarity, only one orientation of the molecule is shown. Atoms marked A are at the symmetry position (1 − x, 1 − y, 1 − z).

Figure 2
The molecule of compound (II)

, showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.

Figure 3
The molecule of compound (III)

, showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.

Figure 4
Stereoview of part of the crystal structure of compound (II)

, showing the formation of a hydrogen-bonded chain of edge-fused rings along [101]. For the sake of clarity, H atoms not involved in the hydrogen bonds shown have been omitted.

Figure 5
Stereoview of part of the crystal structure of compound (II)

, showing the formation of a π-stacked chain of hydrogen-bonded dimers along [110]. For the sake of clarity, H atoms not involved in the hydrogen bonds shown have been omitted.

Figure 6
Stereoview of part of the crystal structure of compound (II)

, showing the formation of a π-stacked chain of hydrogen-bonded dimers along [010]. For the sake of clarity, H atoms not involved in the hydrogen bonds shown have been omitted.

Figure 7
Part of the crystal structure of compound (III)

, showing the formation of a hydrogen-bonded chain along [010]. 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 (x, y − 1, z) and (x, 1 + y, z), respectively.

Figure 8
Part of the crystal structure of compound (III)

, showing the formation of an iodo–nitro chain along [101]. For the sake of clarity, H atoms have been omitted. Atoms marked with an asterisk (*) or a hash (#) are at the symmetry positions ( $[{1\over 2}]$ + x, $[{3\over 2}]$ − y, $[{1\over 2}]$ + z) and (x − $[{1\over 2}]$ , $[{3\over 2}]$ − y, z − $[{1\over 2}]$ ), respectively.

Figure 9
Stereoview of part of the crystal structure of compound (III)

, showing the formation of a (10 $[\overline{1}]$ ) sheet. For the sake of clarity, H atoms not involved in the motifs shown have been omitted.

Experimental

An equimolar mixture of 2-iodobenzaldehyde and the appropriate nitrobenzaldehyde hydrazone (3 mmol of each) in methanol (20 ml) was heated under reflux for 30 min, cooled and then left at room temperature. The precipitate from each reaction was collected after 24 h and recrystallized from 1,2-dichloroethane. While pure samples of compounds (II) (m.p. 458–460 K) and (III) (m.p. 490–491 K) were obtained in this way from 3- and 4-nitrobenzaldehyde hydrazone, respectively, the X-ray analysis showed that the product (m.p. 471–473 K) obtained using 2-nitrobenzaldehyde hydrazone was, in fact, compound (I) co-crystallized with some (E,E)-1,4-bis(2-iodophenyl)-2,3-diaza-1,3-butadiene, despite the sharp melting point.

Compound (I)

Crystal data

C₁₄H₁₀I_1.12N_2.88O_1.76
M_r = 388.69
Monoclinic, C 2/c
a = 15.3033 (8) Å
b = 3.7952 (3) Å
c = 23.3097 (16) Å
β = 97.836 (4)°
V = 1341.16 (16) Å³
Z = 4
D_x = 1.925 Mg m⁻³
Mo Kα radiation
Cell parameters from 1482 reflections
θ = 3.0–27.4°
μ = 2.66 mm⁻¹
T = 120 (2) K
Block, colourless
0.08 × 0.06 × 0.04 mm

Data collection

Nonius KappaCCD area-detector diffractometer
φ and ω scans
Absorption correction: multi-scan(SADABS; Sheldrick, 2003 )T_min = 0.815, T_max = 0.901
6403 measured reflections
1482 independent reflections
1156 reflections with I > 2σ(I)
R_int = 0.066
θ_max = 27.4°
h = −19 → 19
k = −4 → 4
l = −30 → 30

Refinement

Refinement on F²
R[F² > 2σ(F²)] = 0.046
wR(F²) = 0.100
S = 1.07
1482 reflections
104 parameters
H-atom parameters constrained
w = 1/[σ²(F_o²) + (0.0232P)² + 8.8667P] where P = (F_o² + 2F_c²)/3
(Δ/σ)_max = 0.001
Δρ_max = 0.91 e Å⁻³
Δρ_min = −0.82 e Å⁻³

Table 1
Selected torsion angles (°) for (I)

N1ⁱ—N1—C7—C1	−179.5 (5)
N1—C7—C1—C2	−165.9 (4)
C1—C2—N2—O21	−154.3 (7)
Symmetry code: (i) 1-x, 1-y, 1-z.

Compound (II)

Crystal data

C₁₄H₁₀IN₃O₂
M_r = 379.15
Triclinic, $[P \overline 1]$
a = 7.2969 (3) Å
b = 7.3235 (3) Å
c = 13.7939 (6) Å
α = 97.405 (2)°
β = 100.410 (2)°
γ = 107.590 (3)°
V = 677.73 (5) Å³
Z = 2
D_x = 1.858 Mg m⁻³
Mo Kα radiation
Cell parameters from 3120 reflections
θ = 3.0–27.6°
μ = 2.37 mm⁻¹
T = 120 (2) K
Plate, yellow
0.20 × 0.12 × 0.05 mm

Data collection

Nonius KappaCCD area-detector diffractometer
φ and ω scans
Absorption correction: multi-scan(SADABS; Sheldrick, 2003)T_min = 0.649, T_max = 0.891
13 382 measured reflections
3120 independent reflections
2909 reflections with I > 2σ(I)
R_int = 0.029
θ_max = 27.6°
h = −9 → 9
k = −9 → 9
l = −17 → 17

Refinement

Refinement on F²
R[F² > 2σ(F²)] = 0.023
wR(F²) = 0.085
S = 1.28
3120 reflections
181 parameters
H-atom parameters constrained
w = 1/[σ²(F_o²) + (0.0469P)² + 0.3339P] where P = (F_o² + 2F_c²)/3
(Δ/σ)_max = 0.001
Δρ_max = 1.06 e Å⁻³
Δρ_min = −1.04 e Å⁻³

Table 2
Selected torsion angles (°) for (II)

C17—N17—N27—C27	177.5 (3)
N27—N17—C17—C11	−179.4 (3)
N17—N27—C27—C21	−180.0 (3)
N17—C17—C11—C12	−8.9 (4)
N27—C27—C21—C22	−171.0 (3)
C12—C13—N13—O31	−5.3 (4)

Table 3
Hydrogen-bond geometry (Å, °) for (II)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C12—H12⋯I22ⁱ	0.95	3.04	3.972 (3)	168
C25—H25⋯O32ⁱⁱ	0.95	2.50	3.436 (4)	167
C27—H27⋯I22ⁱ	0.95	3.06	3.923 (3)	153
Symmetry codes: (i) 1-x, 1-y, 1-z; (ii) x+1, y, z+1.

Compound (III)

Crystal data

C₁₄H₁₀IN₃O₂
M_r = 379.15
Monoclinic, C 2/c
a = 27.9470 (11) Å
b = 8.0563 (3) Å
c = 13.7464 (5) Å
β = 117.4250 (10)°
V = 2747.16 (18) Å³
Z = 8
D_x = 1.833 Mg m⁻³
Mo Kα radiation
Cell parameters from 4956 reflections
θ = 2.7–32.5°
μ = 2.34 mm⁻¹
T = 293 (2) K
Plate, yellow
0.37 × 0.25 × 0.06 mm

Data collection

Bruker SMART 1000 CCD area-detector diffractometer
φ and ω scans
Absorption correction: multi-scan(SADABS; Bruker, 2000 )T_min = 0.479, T_max = 0.873
15 927 measured reflections
4956 independent reflections
3759 reflections with I > 2σ(I)
R_int = 0.024
θ_max = 32.5°
h = −42 → 40
k = −12 → 12
l = −20 → 17

Refinement

Refinement on F²
R[F² > 2σ(F²)] = 0.030
wR(F²) = 0.079
S = 1.03
4956 reflections
181 parameters
H-atom parameters constrained
w = 1/[σ²(F_o²) + (0.0396P)² + 0.5558P] where P = (F_o² + 2F_c²)/3
(Δ/σ)_max = 0.004
Δρ_max = 0.82 e Å⁻³
Δρ_min = −0.77 e Å⁻³

Table 4
Selected torsion angles (°) for (III)

C17—N17—N27—C27	172.5 (2)
N27—N17—C17—C11	178.31 (19)
N17—N27—C27—C21	178.14 (18)
N17—C17—C11—C12	−175.3 (2)
N27—C27—C21—C22	173.5 (2)
C13—C14—N14—O41	6.9 (3)

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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C12—H12⋯O42ⁱ	0.93	2.58	3.430 (2)	153
Symmetry code: (i) x, y-1, z.

For each of (I) and (III), the systematic absences permitted C2/c and Cc as possible space groups. For each isomer, space group C2/c was selected and confirmed by the subsequent analysis. Crystals of isomer (II) are triclinic. Space group P $[\overline{1}]$ was selected and confirmed by the subsequent analysis. It became apparent at an early stage in the refinement of (I) that the occupancies of the iodo and nitro substituents were not identical, as had been expected. The refined occupancy factors were 0.559 (3) for the iodo substituent and 0.441 (3) for the nitro group; when (I) was refined with these occupancies fixed at $[{1\over 2}]$ , the R factors rose to R = 0.050 and wR₂ = 0.133, with unacceptable displacement parameters for the nitro N atom. All H atoms were located from difference maps and then treated as riding atoms, with C—H distances of 0.95 Å at 120 K and 0.93 Å at 293 K, and with U_iso(H) = 1.2U_eq(C).

Data collection: COLLECT (Nonius, 1998 ) for (I) and (II); SMART (Bruker, 1998 ) for (III). Cell refinement: DENZO (Otwinowski & Minor, 1997 ) and COLLECT for (I) and (II); SAINT (Bruker, 2000) for (III). Data reduction: DENZO and COLLECT for (I) and (II); SAINT (Bruker, 2000) for (III). For all three compounds, structure solution: OSCAIL (McArdle, 2003 ) and SHELXS97 (Sheldrick, 1997 ); structure refinement: OSCAIL and SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003 ); publication software: SHELXL97 and PRPKAPPA (Ferguson, 1999 ).

Supporting information

Crystal structure: contains datablocks global, I, II, III. DOI: 10.1107/S0108270105009248/sk1830sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S0108270105009248/sk1830Isup2.hkl

Structure factors: contains datablock II. DOI: 10.1107/S0108270105009248/sk1830IIsup3.hkl

Structure factors: contains datablock III. DOI: 10.1107/S0108270105009248/sk1830IIIsup4.hkl

Comment top

In the course of our continuing investigation of the interplay between hard and soft (Braga et al., 1995; Desiraju & Steiner, 1999) hydrogen bonds, aromatic π–π stacking interactions and iodo–nitro interactions in simple bis-arene systems, we have studied the supramolecular structures of an extensive series of iodoaryl–nitroaryl compounds, many in several isomeric forms, including examples of sulfonamides (Kelly et al., 2002), benzylideneanilines (Glidewell, Howie et al., 2002; Wardell et al., 2002), benzylanilines (Glidewell, Low et al., 2002; Glidewell, Low, Skakle, Wardell & Wardell, 2004) benzenesulfanylanilines (Glidewell et al., 2003a) and phenylhydrazones (Glidewell et al., 2003b; Glidewell, Low, Skakle & Wardell, 2004). We have now extended this study to the isomeric (E,E)-1-(2-iodophenyl)-4-(nitrophenyl)-2,3-diaza-1,3-butadienes, and here we report on the molecular and supramolecular structures of three such isomers, containing the 2-nitrophenyl, 3-nitrophenyl, or 4-nitrophenyl substituents, compounds (I)–(III), respectively (Figs. 1–3).

The crystallization characteristics of the three isomers (I)–(III) are all different, with (I) crystallizing in C2/c with Z' = 1/2, and a value of Z' = 1 for each of isomers (II) and (III), in space groups P1 and C2/c, respectively. However, the intramolecular geometries are all fairly similar. The central –CH═ N—N═CH– fragment is strictly planar in isomer (I) and approximately so in isomers (II) and (III), and the substituents at each of the C═N bonds adopt (E) configurations. The independent aryl rings are all twisted slightly away from this plane, to the greatest extent in (I) and the least in (III), as shown by the relevant torsion angles (Tables 1, 2 and 4). In addition, the nitro groups are all rotated away from the planes of the adjacent aryl rings, to the greatest extent in (I) and the least in (II). Corresponding bond lengths and angles are all very similar for the three isomers and there are no unusual values. In isomer (I), the population of the iodo site was found to exceed that of the nitro sites, with occupancy factors of 0.559 (3) and 0.441 (3), respectively. We conclude that some reorganization of substituted aryl groups has occurred, either during the synthesis of (I) or during its crystallization, such that a small proportion of (E,E)-1,4-bis(2-iodophenyl)-2,3-diaza-1,3-butadiene has co-crystallized with (I).

The molecules of compound (I) (Fig. 1) lie across inversion centres in space group C2/c, with the iodo and nitro substituents disordered; the reference molecule was selected as that lying across (1/2, 1/2, 1/2). The paucity of direction-specific intermolecular interactions in (I) is striking: there are no intermolecular hydrogen bonds of any kind and no aromatic π–π stacking interactions are present. However, atom I2 at (x, y, z) can make two possible contacts, with either another I2 or with nitro atom O21, both at (1 − x, y, 3/2 − z), i.e. both components of the molecule of (I) centred across (1/2, 1/2, 1), and with dimensions I···Iⁱ 3.247 (2) Å and C—I···Iⁱ 163.3 (2)°, and I···Oⁱ 3.312 (8) Å, C—I···Oⁱ 167.1 (2)° [symmetry code: (i) 1 − x, y, 3/2 − z]. It is convenient to consider first the possible consequences of these interactions in pure (I), and then to consider the effects of the co-crystallized diiodo compound. If adjacent molecules of (I) along [001] are consistently aligned in a head-to-tail fashion, then the iodo–nitro interaction generates a C(11) chain (Starbuck et al., 1999) along [001]. If, however, adjacent molecules are aligned in a head-to-head fashion, the I···I contact can only link the molecules together in pairs.

The angular properties of this C—I···I interaction are admirably consistent with generalizations proposed (Ramasubbu et al., 1986) from the results of database analysis, namely that in structures where X···X distances (X = halogen) are significantly less than the van der Waals sum, the observed C—X···X angles are clustered either around 180° or around 90°. These authors also note that, in such interactions, X···X distances are commonly observed ca 0.5 Å below the conventional van der Waals sum of 3.90 Å for I···I (Bondi, 1964). The short I···I contact distance here is well below the van der Waals sum, even allowing for the polar flattening effect (Nyburg & Faerman, 1985), and may point to an avoidance of such I···I contacts wherever possible. Such avoidance is readily achieved by the head-to-tail alignment of the molecules of (I) within an [001] chain, so that disorder of the molecules is correlated in one direction. This neither implies nor requires any correlation between adjacent [001] chains. Such short contacts can be avoided, even when a molecule of the diiodo analogue is present: such a molecule can readily form two iodo–nitro interactions, one at each I atom. Each such diiodo molecule would, in these circumstances, simply effect a reversal in the polarity of a chain formed by molecules of (I). Overall, therefore, we conclude that molecules of (I) are linked into [001] chains by a two-centre iodo–nitro interaction, with no short I···I contacts.

The molecules of compound (II) (Fig. 2) are linked into a three-dimensional framework by a combination of C—H···O and C—H···I hydrogen bonds and by two independent aromatic π–π stacking interactions. The hydrogen bonds together generate a one-dimensional substructure, and each of the stacking interactions in combination with the C—H···I hydrogen bonds independently generates a further one-dimensional substructure. Accordingly, the formation of the framework is most readily analysed and discussed in terms of these three simple substructures.

Aryl atom C12 and methine atom C27 in the molecule at (x, y, z) both act as hydrogen-bond donors to iodine I22 in the molecule at (1 − x, 1 − y, 1 − z), thereby generating a centrosymmetric dimer characterized by an array of three edge-fused [R₂¹(9)][R₂²(10)][R₂¹(9)] rings (Bernstein et al., 1995), centred at (1/2, 1/2, 1/2) (Fig. 4). These complex dimers are themselves linked by a further hydrogen bond, of the C—H···O type: the aryl atom C25 in the molecule at (x, y, z) acts as donor to nitro atom O32 in the molecule at (1 + x, y, 1 + z), so forming a C(13) chain running parallel to the [101] direction. Propagation of this hydrogen bond by translation and inversion then links the dimers into a [101] ribbon, in the form of a chain of edge-fused rings, with R₄⁴(22) rings centred at (n, 1/2, n) (n = zero or integer), alternating with R₂²(10) rings centred at (1/2 + n, 1/2, 1/2 + n) (n = zero or integer), with the R₂¹(9) rings on the two edges of the ribbon (Fig. 4).

The dimers generated by the C—H···I hydrogen bonds in (II) are also linked by two independent π–π stacking interactions to form two further one-dimensional substructures. The first of these involves the centrosymmetric pair of molecules at (x, y, z) and (−x, −y, 1 − z), which are components of the dimers centred at (1/2, 1/2, 1/2) and (−1/2, −1/2, 1/2), respectively. The nitrated ring at (x, y, z) and the iodinated ring at (−x, −y, 1 − z) are nearly parallel, with a dihedral angle between their planes of only 2.3 (2)°. The interplanar spacing is ca 3.47 Å and the ring-centroid separation is 3.767 (2) Å, corresponding to a near-ideal centroid offset of ca 1.47 Å. Propagation of this interaction by inversion then links the hydrogen-bonded dimers into a π-stacked chain running parallel to the [110] direction (Fig. 5).

The second stacking interaction involves the centrosymmetric pair of molecules at (x, y, z) and (1 − x, −y, 1 − z), components of hydrogen-bonded dimers centred at (1/2, 1/2, 1/2) and (1/2, −1/2, 1/2). Again, the adjacent ring planes make a dihedral angle of 2.3 (2)°, but now the interplanar spacing is ca 3.42 Å, with a ring-centroid separation of 3.725 (2) Å, giving a ring-centroid offset of ca 1.48 Å. Propagation of this interaction then generates a chain of dimers along [010] (Fig. 6). The combination of the independent chains along [101], [110] and [010] is sufficient to link all of the molecules of (II) into a single three-dimensional framework. If is notable, however, that iodo–nitro interactions are absent from the structure of (II).

The molecules of compound (III) (Fig. 3) are linked into sheets by a combination of a rather weak C—H···O hydrogen bond and a two-centre iodo–nitro interaction, and again it is convenient to consider the effect of each of these interactions in turn. Aryl atom C12 in the molecule at (x, y, z) acts as hydrogen-bond donor to nitro atom O42 in the molecule at (x, −1 + y, z), so generating by translation a C(6) chain running parallel to the [010] direction (Fig. 7); eight chains of this type pass through each unit cell. In addition, atom I22 in the molecule at (x, y, z) forms a nearly linear two-centre I···O interaction with nitro atom O41 in the molecule at (1/2 + x, 3/2 − y, 1/2 + z), with dimensions I···Oⁱ 3.362 (2) Å, C—I···Oⁱ 171.62 (6)° and I···Oⁱ—Nⁱ 113.6 (2)° [symmetry code: (i) 1/2 + x, 3/2 − y, 1/2 + z]. In this way, a C(13) (Starbuck et al., 1999) chain is formed running parallel to the [101] direction and generated by the n-glide plane at y = 3/4 (Fig. 8). The combination of the [010] and [101] chains generates a (101) sheet in the form of a (4,4) net built from a single type of R₄⁴(32) ring (Fig. 9). Four sheets of this type pass through each unit cell, but there are no direction-specific interactions between adjacent sheets. In particular, C—H···π(arene) hydrogen bonds and aromatic π–π stacking interactions are absent from the structure of (III).

Experimental top

An equimolar mixture of 2-iodobenzaldehyde and the appropriate nitrobenzaldehyde hydrazone (3 mmol of each) in methanol (20 ml) was heated under reflux for 30 min, cooled and then left at room temperature. The precipitate from each reaction was collected after 24 h and recrystallized from 1,2-dichloroethane. While pure samples of compounds (II) (m.p. 458–460 K) and (III) (m.p. 490–491 K) were obtained in this way from 3- and 4-nitrobenzaldehyde hydrazones, respectively, the X-ray analysis showed that the product (m.p. 471–473 K) obtained using 2-nitrobenzaldehyde hydrazone was, in fact, compound (I) co-crystallized with some (E,E)-1,4-bis(2-iodophenyl)-2,3-diaza-1,3-butadiene, despite the sharp melting point.

Computing details top

Data collection: COLLECT (Nonius, 1998) for (I), (II); SMART (Bruker, 1998) for (III). Cell refinement: DENZO (Otwinowski & Minor, 1997) and COLLECT for (I), (II); SAINT (Bruker, 2000) for (III). Data reduction: DENZO and COLLECT for (I), (II); SAINT (Bruker, 2000) for (III). For all compounds, 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

	Fig. 1. The molecule of compound (I), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level. For the sake of clarity, only one orientation of the molecule is shown. Atoms marked A are at the symmetry position (1 − x, 1 − y, 1 − z).
	Fig. 2. The molecule of compound (II), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
	Fig. 3. The molecule of compound (III), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
	Fig. 4. Stereoview of part of the crystal structure of compound (II), showing the formation of a hydrogen-bonded chain of edge-fused rings along [101]. For the sake of clarity, H atoms not involved in the hydrogen bonds shown have been omitted.
	Fig. 5. Stereoview of part of the crystal structure of compound (II), showing the formation of a π-stacked chain of hydrogen-bonded dimers along [110]. For the sake of clarity, H atoms not involved in the hydrogen bonds shown have been omitted.
	Fig. 6. Stereoview of part of the crystal structure of compound (II), showing the formation of a π-stacked chain of hydrogen-bonded dimers along [010]. For the sake of clarity, H atoms not involved in the hydrogen bonds shown have been omitted.
	Fig. 7. Part of the crystal structure of compound (III), showing the formation of a hydrogen-bonded chain along [010]. 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 (x, −1 + y, z) and (x, 1 + y, z), respectively.
	Fig. 8. Part of the crystal structure of compound (III), showing the formation of an iodo–nitro chain along [101]. For the sake of clarity, H atoms have been omitted. Atoms marked with an asterisk (*) or a hash (#) are at the symmetry positions (1/2 + x, 3/2 − y, 1/2 + z) and (−1/2 + x, 3/2 − y, −1/2 + z), respectively.
	Fig. 9. Stereoview of part of the crystal structure of compound (III), showing the formation of a (101) sheet. For the sake of clarity, H atoms not involved in the motifs shown have been omitted.

(I) 1-(2-Iodophenyl)-4-(2-nitrophenyl)-2,3-diaza-1,3-butadiene top

Crystal data top

C₁₄H₁₀I_1.12N_2.88O_1.76	F(000) = 750.2
M_r = 388.69	D_x = 1.925 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 1482 reflections
a = 15.3033 (8) Å	θ = 3.0–27.4°
b = 3.7952 (3) Å	µ = 2.66 mm⁻¹
c = 23.3097 (16) Å	T = 120 K
β = 97.836 (4)°	Block, colourless
V = 1341.16 (16) Å³	0.08 × 0.06 × 0.04 mm
Z = 4

Data collection top

Nonius KappaCCD area-detector diffractometer	1482 independent reflections
Radiation source: Bruker-Nonius FR591 rotating anode	1156 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.066
Detector resolution: 9.091 pixels mm^-1	θ_max = 27.4°, θ_min = 3.0°
ϕ and ω scans	h = −19→19
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	k = −4→4
T_min = 0.815, T_max = 0.901	l = −30→30
6403 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.100	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.0232P)² + 8.8667P] where P = (F_o² + 2F_c²)/3
1482 reflections	(Δ/σ)_max = 0.001
104 parameters	Δρ_max = 0.91 e Å⁻³
2 restraints	Δρ_min = −0.82 e Å⁻³

Crystal data top

C₁₄H₁₀I_1.12N_2.88O_1.76	V = 1341.16 (16) Å³
M_r = 388.69	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 15.3033 (8) Å	µ = 2.66 mm⁻¹
b = 3.7952 (3) Å	T = 120 K
c = 23.3097 (16) Å	0.08 × 0.06 × 0.04 mm
β = 97.836 (4)°

Data collection top

Nonius KappaCCD area-detector diffractometer	1482 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	1156 reflections with I > 2σ(I)
T_min = 0.815, T_max = 0.901	R_int = 0.066
6403 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.046	2 restraints
wR(F²) = 0.100	H-atom parameters constrained
S = 1.07	Δρ_max = 0.91 e Å⁻³
1482 reflections	Δρ_min = −0.82 e Å⁻³
104 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
I2	0.56268 (4)	0.07489 (18)	0.69915 (2)	0.0395 (3)	0.559 (3)
O21	0.6152 (5)	0.071 (2)	0.7343 (3)	0.043 (2)	0.441 (3)
O22	0.5247 (5)	−0.003 (2)	0.6555 (3)	0.044 (2)	0.441 (3)
N1	0.5447 (2)	0.4686 (11)	0.50972 (15)	0.0358 (10)
N2	0.5966 (4)	0.073 (2)	0.6812 (3)	0.0294 (9)	0.441 (3)
C1	0.6477 (3)	0.3319 (11)	0.59300 (17)	0.0256 (9)
C2	0.6660 (2)	0.1870 (12)	0.64815 (17)	0.0294 (9)
C3	0.7513 (3)	0.1207 (11)	0.67384 (17)	0.0286 (10)
C4	0.8214 (3)	0.1991 (12)	0.64419 (18)	0.0314 (10)
C5	0.8057 (3)	0.3448 (12)	0.58927 (19)	0.0325 (11)
C6	0.7204 (3)	0.4096 (12)	0.56453 (17)	0.0287 (10)
C7	0.5585 (3)	0.4024 (12)	0.56398 (17)	0.0309 (10)
H7	0.5104	0.3989	0.5857	0.037*
H3	0.7618	0.0219	0.7116	0.034*
H4	0.8801	0.1530	0.6615	0.038*
H5	0.8536	0.3998	0.5688	0.039*
H6	0.7104	0.5102	0.5269	0.034*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0271 (18)	0.054 (3)	0.0245 (18)	0.0082 (17)	−0.0024 (14)	0.0003 (17)
C7	0.031 (2)	0.036 (3)	0.026 (2)	0.0024 (19)	0.0042 (17)	−0.0020 (19)
C1	0.025 (2)	0.026 (2)	0.024 (2)	0.0043 (16)	−0.0019 (16)	−0.0012 (17)
C2	0.0263 (19)	0.039 (2)	0.0220 (18)	0.0018 (17)	0.0013 (15)	−0.0023 (16)
I2	0.0272 (3)	0.0616 (4)	0.0286 (4)	−0.0023 (3)	0.0002 (3)	0.0083 (3)
N2	0.0263 (19)	0.039 (2)	0.0220 (18)	0.0018 (17)	0.0013 (15)	−0.0023 (16)
O21	0.034 (4)	0.065 (6)	0.027 (4)	−0.008 (4)	0.000 (4)	0.007 (4)
O22	0.030 (4)	0.065 (6)	0.039 (5)	−0.016 (4)	0.012 (3)	−0.002 (4)
C3	0.031 (2)	0.031 (2)	0.022 (2)	0.0007 (18)	−0.0026 (16)	−0.0015 (17)
C4	0.023 (2)	0.036 (3)	0.034 (2)	0.0005 (18)	−0.0019 (17)	−0.007 (2)
C5	0.031 (2)	0.037 (3)	0.031 (2)	−0.0032 (19)	0.0081 (18)	−0.0070 (19)
C6	0.034 (2)	0.031 (2)	0.022 (2)	−0.0013 (19)	0.0052 (16)	−0.0011 (18)

Geometric parameters (Å, º) top

N1—C7	1.279 (5)	N2—O22	1.213 (10)
N1—N1ⁱ	1.401 (7)	N2—O21	1.232 (10)
C7—C1	1.463 (6)	C3—C4	1.385 (6)
C7—H7	0.95	C3—H3	0.95
C1—C2	1.391 (5)	C4—C5	1.385 (6)
C1—C6	1.402 (6)	C4—H4	0.95
C2—C3	1.383 (5)	C5—C6	1.375 (6)
C2—N2	1.4600 (3)	C5—H5	0.95
C2—I2	2.147 (4)	C6—H6	0.95

C7—N1—N1ⁱ	112.1 (4)	O21—N2—C2	116.5 (6)
N1—C7—C1	120.8 (4)	C2—C3—C4	119.6 (4)
N1—C7—H7	119.6	C2—C3—H3	120.2
C1—C7—H7	119.6	C4—C3—H3	120.2
C2—C1—C6	116.6 (3)	C3—C4—C5	119.9 (4)
C2—C1—C7	123.9 (4)	C3—C4—H4	120.0
C6—C1—C7	119.5 (4)	C5—C4—H4	120.0
C3—C2—C1	122.1 (3)	C6—C5—C4	119.6 (4)
C3—C2—N2	115.4 (4)	C6—C5—H5	120.2
C1—C2—N2	122.4 (4)	C4—C5—H5	120.2
C3—C2—I2	116.6 (3)	C5—C6—C1	122.2 (4)
C1—C2—I2	121.3 (3)	C5—C6—H6	118.9
O22—N2—O21	124.4 (6)	C1—C6—H6	118.9
O22—N2—C2	119.1 (6)

N1ⁱ—N1—C7—C1	−179.5 (5)	C3—C2—N2—O21	29.7 (10)
N1—C7—C1—C2	−165.9 (4)	C1—C2—N2—O21	−154.3 (7)
N1—C7—C1—C6	13.6 (7)	C1—C2—C3—C4	−0.1 (7)
C6—C1—C2—C3	−0.2 (6)	N2—C2—C3—C4	175.9 (5)
C7—C1—C2—C3	179.2 (4)	I2—C2—C3—C4	−177.6 (3)
C6—C1—C2—N2	−176.0 (5)	C2—C3—C4—C5	0.3 (7)
C7—C1—C2—N2	3.5 (8)	C3—C4—C5—C6	−0.2 (7)
C6—C1—C2—I2	177.2 (3)	C4—C5—C6—C1	−0.2 (7)
C7—C1—C2—I2	−3.4 (6)	C2—C1—C6—C5	0.4 (6)
C3—C2—N2—O22	−152.6 (7)	C7—C1—C6—C5	−179.1 (4)
C1—C2—N2—O22	23.4 (11)

Symmetry code: (i) −x+1, −y+1, −z+1.

(II) 1-(2-Iodophenyl)-4-(3-nitrophenyl)-2,3-diaza-1,3-butadiene top

Crystal data top

C₁₄H₁₀IN₃O₂	Z = 2
M_r = 379.15	F(000) = 368
Triclinic, P1	D_x = 1.858 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.2969 (3) Å	Cell parameters from 3120 reflections
b = 7.3235 (3) Å	θ = 3.0–27.6°
c = 13.7939 (6) Å	µ = 2.37 mm⁻¹
α = 97.405 (2)°	T = 120 K
β = 100.410 (2)°	Plate, yellow
γ = 107.590 (3)°	0.20 × 0.12 × 0.05 mm
V = 677.73 (5) Å³

Data collection top

Nonius KappaCCD area-detector diffractometer	3120 independent reflections
Radiation source: Bruker-Nonius FR91 rotating anode	2909 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.029
Detector resolution: 9.091 pixels mm^-1	θ_max = 27.6°, θ_min = 3.0°
ϕ and ω scans	h = −9→9
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	k = −9→9
T_min = 0.649, T_max = 0.891	l = −17→17
13382 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.023	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.085	H-atom parameters constrained
S = 1.28	w = 1/[σ²(F_o²) + (0.0469P)² + 0.3339P] where P = (F_o² + 2F_c²)/3
3120 reflections	(Δ/σ)_max = 0.001
181 parameters	Δρ_max = 1.06 e Å⁻³
0 restraints	Δρ_min = −1.04 e Å⁻³

Crystal data top

C₁₄H₁₀IN₃O₂	γ = 107.590 (3)°
M_r = 379.15	V = 677.73 (5) Å³
Triclinic, P1	Z = 2
a = 7.2969 (3) Å	Mo Kα radiation
b = 7.3235 (3) Å	µ = 2.37 mm⁻¹
c = 13.7939 (6) Å	T = 120 K
α = 97.405 (2)°	0.20 × 0.12 × 0.05 mm
β = 100.410 (2)°

Data collection top

Nonius KappaCCD area-detector diffractometer	3120 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	2909 reflections with I > 2σ(I)
T_min = 0.649, T_max = 0.891	R_int = 0.029
13382 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.023	0 restraints
wR(F²) = 0.085	H-atom parameters constrained
S = 1.28	Δρ_max = 1.06 e Å⁻³
3120 reflections	Δρ_min = −1.04 e Å⁻³
181 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
C11	−0.0567 (4)	−0.2954 (4)	0.3271 (2)	0.0187 (5)
C12	−0.0674 (4)	−0.1709 (4)	0.2594 (2)	0.0191 (5)
C13	−0.1845 (4)	−0.2506 (4)	0.1637 (2)	0.0186 (6)
N13	−0.1969 (4)	−0.1203 (4)	0.0922 (2)	0.0260 (6)
O31	−0.1152 (4)	0.0552 (3)	0.1219 (2)	0.0417 (7)
O32	−0.2923 (4)	−0.1949 (4)	0.00608 (18)	0.0428 (7)
C14	−0.2920 (4)	−0.4480 (4)	0.1311 (2)	0.0193 (6)
C15	−0.2819 (4)	−0.5700 (4)	0.1985 (2)	0.0228 (6)
C16	−0.1673 (4)	−0.4955 (4)	0.2960 (2)	0.0215 (6)
C17	0.0658 (4)	−0.2245 (4)	0.4290 (2)	0.0203 (6)
N17	0.1897 (4)	−0.0501 (4)	0.45944 (19)	0.0199 (5)
N27	0.2894 (4)	−0.0203 (4)	0.55996 (19)	0.0210 (5)
C21	0.5397 (4)	0.2117 (4)	0.6929 (2)	0.0172 (5)
C22	0.6637 (4)	0.4053 (4)	0.7336 (2)	0.0179 (5)
I22	0.69346 (3)	0.62753 (2)	0.648300 (13)	0.02472 (9)
C23	0.7740 (4)	0.4599 (4)	0.8326 (2)	0.0215 (6)
C24	0.7650 (4)	0.3206 (5)	0.8921 (2)	0.0234 (6)
C25	0.6456 (5)	0.1273 (5)	0.8532 (2)	0.0247 (6)
C26	0.5348 (4)	0.0752 (4)	0.7553 (2)	0.0217 (6)
C27	0.4188 (4)	0.1501 (4)	0.5906 (2)	0.0201 (6)
H12	0.0040	−0.0349	0.2787	0.023*
H14	−0.3699	−0.4974	0.0643	0.023*
H15	−0.3537	−0.7058	0.1783	0.027*
H16	−0.1636	−0.5807	0.3421	0.026*
H17	0.0535	−0.3110	0.4750	0.024*
H23	0.8547	0.5920	0.8592	0.026*
H24	0.8405	0.3568	0.9596	0.028*
H25	0.6404	0.0315	0.8939	0.030*
H26	0.4530	−0.0568	0.7298	0.026*
H27	0.4364	0.2384	0.5455	0.024*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C11	0.0153 (12)	0.0191 (13)	0.0194 (14)	0.0037 (10)	0.0029 (10)	0.0022 (11)
C12	0.0179 (13)	0.0164 (13)	0.0208 (14)	0.0037 (10)	0.0040 (11)	0.0016 (11)
C13	0.0176 (13)	0.0183 (13)	0.0192 (14)	0.0046 (11)	0.0040 (11)	0.0049 (11)
N13	0.0308 (14)	0.0196 (12)	0.0240 (13)	0.0047 (10)	0.0023 (11)	0.0063 (10)
O31	0.0569 (16)	0.0186 (11)	0.0346 (14)	−0.0006 (11)	−0.0059 (12)	0.0087 (10)
O32	0.0652 (18)	0.0314 (13)	0.0199 (12)	0.0072 (12)	−0.0065 (12)	0.0079 (10)
C14	0.0157 (13)	0.0194 (14)	0.0177 (13)	0.0026 (10)	−0.0009 (11)	0.0006 (11)
C15	0.0212 (14)	0.0160 (13)	0.0248 (15)	0.0007 (11)	0.0002 (12)	0.0026 (11)
C16	0.0193 (14)	0.0206 (14)	0.0222 (14)	0.0042 (11)	0.0014 (11)	0.0064 (11)
C17	0.0206 (14)	0.0217 (14)	0.0178 (14)	0.0069 (11)	0.0025 (11)	0.0036 (11)
N17	0.0200 (12)	0.0206 (12)	0.0156 (12)	0.0057 (10)	0.0003 (9)	−0.0001 (10)
N27	0.0208 (12)	0.0216 (12)	0.0164 (12)	0.0040 (10)	0.0000 (10)	0.0024 (10)
C21	0.0173 (13)	0.0170 (13)	0.0162 (13)	0.0048 (10)	0.0036 (10)	0.0021 (10)
C22	0.0197 (13)	0.0153 (12)	0.0192 (14)	0.0057 (10)	0.0042 (11)	0.0057 (11)
I22	0.02800 (14)	0.01728 (12)	0.02467 (14)	0.00285 (9)	0.00159 (9)	0.00725 (8)
C23	0.0218 (14)	0.0191 (13)	0.0194 (14)	0.0040 (11)	0.0022 (11)	0.0000 (11)
C24	0.0209 (14)	0.0296 (16)	0.0161 (14)	0.0063 (12)	0.0003 (11)	0.0025 (12)
C25	0.0252 (15)	0.0256 (15)	0.0224 (15)	0.0069 (12)	0.0028 (12)	0.0091 (12)
C26	0.0216 (14)	0.0156 (13)	0.0244 (15)	0.0022 (11)	0.0026 (11)	0.0054 (11)
C27	0.0210 (14)	0.0204 (14)	0.0189 (14)	0.0069 (11)	0.0040 (11)	0.0052 (11)

Geometric parameters (Å, º) top

C11—C12	1.394 (4)	N17—N27	1.401 (3)
C11—C16	1.407 (4)	N27—C27	1.278 (4)
C11—C17	1.457 (4)	C27—C21	1.456 (4)
C12—C13	1.380 (4)	C27—H27	0.95
C12—H12	0.95	C21—C26	1.397 (4)
C13—C14	1.388 (4)	C21—C22	1.407 (4)
C13—N13	1.467 (4)	C22—C23	1.394 (4)
N13—O31	1.220 (3)	C22—I22	2.109 (3)
N13—O32	1.224 (4)	C23—C24	1.383 (4)
C14—C15	1.378 (4)	C23—H23	0.95
C14—H14	0.95	C24—C25	1.393 (4)
C15—C16	1.391 (4)	C24—H24	0.95
C15—H15	0.95	C25—C26	1.381 (4)
C16—H16	0.95	C25—H25	0.95
C17—N17	1.285 (4)	C26—H26	0.95
C17—H17	0.95

C12—C11—C16	119.1 (3)	C17—N17—N27	111.4 (2)
C12—C11—C17	121.9 (3)	C27—N27—N17	112.4 (2)
C16—C11—C17	119.0 (3)	N27—C27—C21	121.4 (3)
C13—C12—C11	118.2 (3)	N27—C27—H27	119.3
C13—C12—H12	120.9	C21—C27—H27	119.3
C11—C12—H12	120.9	C26—C21—C22	117.3 (3)
C12—C13—C14	123.6 (3)	C26—C21—C27	119.7 (3)
C12—C13—N13	118.5 (3)	C22—C21—C27	123.1 (3)
C14—C13—N13	117.9 (3)	C23—C22—C21	121.5 (3)
O31—N13—O32	123.7 (3)	C23—C22—I22	116.5 (2)
O31—N13—C13	118.6 (3)	C21—C22—I22	122.0 (2)
O32—N13—C13	117.6 (3)	C24—C23—C22	119.6 (3)
C15—C14—C13	117.9 (3)	C24—C23—H23	120.2
C15—C14—H14	121.0	C22—C23—H23	120.2
C13—C14—H14	121.0	C23—C24—C25	120.1 (3)
C14—C15—C16	120.4 (3)	C23—C24—H24	119.9
C14—C15—H15	119.8	C25—C24—H24	119.9
C16—C15—H15	119.8	C26—C25—C24	119.9 (3)
C15—C16—C11	120.8 (3)	C26—C25—H25	120.1
C15—C16—H16	119.6	C24—C25—H25	120.1
C11—C16—H16	119.6	C25—C26—C21	121.7 (3)
N17—C17—C11	122.9 (3)	C25—C26—H26	119.1
N17—C17—H17	118.5	C21—C26—H26	119.1
C11—C17—H17	118.5

C17—N17—N27—C27	177.5 (3)	C14—C15—C16—C11	−1.2 (5)
N27—N17—C17—C11	−179.4 (3)	C12—C11—C16—C15	1.7 (4)
N17—N27—C27—C21	−180.0 (3)	C17—C11—C16—C15	−178.3 (3)
N17—C17—C11—C12	−8.9 (4)	C16—C11—C17—N17	171.1 (3)
N27—C27—C21—C22	−171.0 (3)	N27—C27—C21—C26	8.8 (4)
C12—C13—N13—O31	−5.3 (4)	C26—C21—C22—C23	−1.4 (4)
C16—C11—C12—C13	−1.0 (4)	C27—C21—C22—C23	178.5 (3)
C17—C11—C12—C13	179.0 (3)	C26—C21—C22—I22	178.5 (2)
C11—C12—C13—C14	−0.1 (4)	C27—C21—C22—I22	−1.6 (4)
C11—C12—C13—N13	179.9 (3)	C21—C22—C23—C24	1.3 (4)
C14—C13—N13—O31	174.7 (3)	I22—C22—C23—C24	−178.5 (2)
C12—C13—N13—O32	175.9 (3)	C22—C23—C24—C25	−0.4 (4)
C14—C13—N13—O32	−4.1 (4)	C23—C24—C25—C26	−0.5 (5)
C12—C13—C14—C15	0.6 (4)	C24—C25—C26—C21	0.5 (5)
N13—C13—C14—C15	−179.4 (3)	C22—C21—C26—C25	0.4 (4)
C13—C14—C15—C16	0.1 (4)	C27—C21—C26—C25	−179.4 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C12—H12···I22ⁱ	0.95	3.04	3.972 (3)	168
C25—H25···O32ⁱⁱ	0.95	2.50	3.436 (4)	167
C27—H27···I22ⁱ	0.95	3.06	3.923 (3)	153

Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x+1, y, z+1.

(III) 1-(2-Iodophenyl)-4-(4-nitrophenyl)-2,3-diaza-1,3-butadiene top

Crystal data top

C₁₄H₁₀IN₃O₂	F(000) = 1472
M_r = 379.15	D_x = 1.833 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 4956 reflections
a = 27.9470 (11) Å	θ = 2.7–32.5°
b = 8.0563 (3) Å	µ = 2.34 mm⁻¹
c = 13.7464 (5) Å	T = 293 K
β = 117.425 (1)°	Plate, yellow
V = 2747.16 (18) Å³	0.37 × 0.25 × 0.06 mm
Z = 8

Data collection top

Bruker SMART 1000 CCD area-detector diffractometer	4956 independent reflections
Radiation source: fine-focus sealed tube	3759 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.024
ϕ and ω scans	θ_max = 32.5°, θ_min = 2.7°
Absorption correction: multi-scan (SADABS; Bruker, 2000)	h = −42→40
T_min = 0.479, T_max = 0.873	k = −12→12
15927 measured reflections	l = −20→17

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.030	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.079	H-atom parameters constrained
S = 1.03	w = 1/[σ²(F_o²) + (0.0396P)² + 0.5558P] where P = (F_o² + 2F_c²)/3
4956 reflections	(Δ/σ)_max = 0.004
181 parameters	Δρ_max = 0.82 e Å⁻³
0 restraints	Δρ_min = −0.77 e Å⁻³

Crystal data top

C₁₄H₁₀IN₃O₂	V = 2747.16 (18) Å³
M_r = 379.15	Z = 8
Monoclinic, C2/c	Mo Kα radiation
a = 27.9470 (11) Å	µ = 2.34 mm⁻¹
b = 8.0563 (3) Å	T = 293 K
c = 13.7464 (5) Å	0.37 × 0.25 × 0.06 mm
β = 117.425 (1)°

Data collection top

Bruker SMART 1000 CCD area-detector diffractometer	4956 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2000)	3759 reflections with I > 2σ(I)
T_min = 0.479, T_max = 0.873	R_int = 0.024
15927 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.030	0 restraints
wR(F²) = 0.079	H-atom parameters constrained
S = 1.03	Δρ_max = 0.82 e Å⁻³
4956 reflections	Δρ_min = −0.77 e Å⁻³
181 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
C11	0.42316 (7)	0.5067 (2)	0.26822 (16)	0.0401 (4)
C12	0.36835 (8)	0.4950 (2)	0.19596 (18)	0.0463 (5)
C13	0.33708 (8)	0.6365 (3)	0.15928 (18)	0.0469 (5)
C14	0.36171 (8)	0.7876 (2)	0.19700 (17)	0.0383 (4)
N14	0.32811 (7)	0.9388 (2)	0.16194 (15)	0.0476 (4)
O41	0.27938 (6)	0.9224 (2)	0.10983 (16)	0.0699 (5)
O42	0.35057 (7)	1.07302 (19)	0.18811 (15)	0.0639 (5)
C15	0.41577 (9)	0.8045 (2)	0.26592 (19)	0.0513 (5)
C16	0.44662 (8)	0.6614 (3)	0.30137 (19)	0.0532 (5)
C17	0.45442 (7)	0.3531 (2)	0.30847 (17)	0.0440 (4)
N17	0.50375 (7)	0.3552 (2)	0.38000 (15)	0.0483 (4)
N27	0.52446 (7)	0.1932 (2)	0.40763 (16)	0.0494 (4)
C21	0.60349 (7)	0.0332 (2)	0.50941 (16)	0.0396 (4)
C22	0.65958 (7)	0.0228 (2)	0.56831 (16)	0.0394 (4)
I22	0.710042 (5)	0.231190 (19)	0.599270 (13)	0.05266 (7)
C23	0.68461 (8)	−0.1293 (3)	0.60571 (18)	0.0493 (5)
C24	0.65457 (11)	−0.2720 (3)	0.5847 (2)	0.0545 (6)
C25	0.59931 (11)	−0.2648 (2)	0.5265 (2)	0.0530 (5)
C26	0.57407 (8)	−0.1140 (3)	0.49012 (18)	0.0481 (5)
C27	0.57486 (8)	0.1909 (2)	0.46916 (18)	0.0438 (4)
H12	0.3527	0.3913	0.1722	0.056*
H13	0.3005	0.6299	0.1106	0.056*
H15	0.4313	0.9088	0.2882	0.062*
H16	0.4834	0.6694	0.3479	0.064*
H17	0.4377	0.2517	0.2810	0.053*
H23	0.7220	−0.1347	0.6453	0.059*
H24	0.6716	−0.3736	0.6098	0.065*
H25	0.5790	−0.3615	0.5118	0.064*
H26	0.5366	−0.1102	0.4519	0.058*
H27	0.5939	0.2902	0.4891	0.053*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C11	0.0332 (8)	0.0383 (8)	0.0434 (10)	0.0042 (6)	0.0132 (8)	0.0019 (7)
C12	0.0348 (9)	0.0369 (8)	0.0573 (13)	−0.0003 (7)	0.0128 (9)	−0.0006 (8)
C13	0.0307 (8)	0.0446 (10)	0.0563 (12)	0.0024 (7)	0.0122 (9)	0.0034 (9)
C14	0.0346 (8)	0.0379 (8)	0.0406 (10)	0.0072 (7)	0.0158 (8)	0.0047 (7)
N14	0.0475 (9)	0.0431 (9)	0.0510 (10)	0.0122 (7)	0.0216 (8)	0.0096 (7)
O41	0.0411 (8)	0.0560 (9)	0.0981 (14)	0.0144 (7)	0.0198 (9)	0.0165 (9)
O42	0.0654 (10)	0.0368 (7)	0.0739 (11)	0.0065 (7)	0.0186 (9)	0.0019 (7)
C15	0.0446 (10)	0.0356 (9)	0.0565 (13)	−0.0005 (8)	0.0087 (10)	−0.0025 (8)
C16	0.0332 (9)	0.0423 (10)	0.0610 (14)	0.0027 (7)	0.0019 (9)	−0.0008 (9)
C17	0.0355 (9)	0.0385 (9)	0.0529 (12)	0.0043 (7)	0.0160 (8)	0.0025 (8)
N17	0.0370 (8)	0.0384 (8)	0.0605 (11)	0.0071 (6)	0.0147 (8)	0.0071 (7)
N27	0.0364 (8)	0.0394 (8)	0.0609 (12)	0.0070 (6)	0.0126 (8)	0.0077 (7)
C21	0.0327 (8)	0.0381 (8)	0.0434 (10)	0.0032 (6)	0.0137 (8)	0.0039 (7)
C22	0.0318 (8)	0.0444 (9)	0.0384 (10)	0.0020 (7)	0.0130 (7)	0.0027 (7)
I22	0.03665 (8)	0.05426 (9)	0.05660 (11)	−0.00759 (5)	0.01253 (7)	−0.00546 (6)
C23	0.0376 (9)	0.0529 (11)	0.0515 (12)	0.0109 (8)	0.0155 (9)	0.0101 (9)
C24	0.0557 (13)	0.0451 (10)	0.0630 (15)	0.0161 (9)	0.0276 (12)	0.0141 (9)
C25	0.0533 (13)	0.0391 (9)	0.0665 (16)	−0.0001 (8)	0.0276 (12)	0.0056 (9)
C26	0.0369 (9)	0.0426 (10)	0.0574 (13)	−0.0003 (7)	0.0154 (9)	0.0040 (9)
C27	0.0339 (8)	0.0381 (9)	0.0521 (12)	0.0023 (7)	0.0135 (8)	0.0044 (8)

Geometric parameters (Å, º) top

C11—C16	1.384 (3)	N17—N27	1.407 (2)
C11—C12	1.393 (3)	N27—C27	1.266 (2)
C11—C17	1.469 (2)	C27—C21	1.467 (2)
C12—C13	1.383 (3)	C27—H27	0.93
C12—H12	0.93	C21—C22	1.397 (2)
C13—C14	1.376 (3)	C21—C26	1.397 (3)
C13—H13	0.93	C22—C23	1.387 (3)
C14—C15	1.371 (3)	C22—I22	2.1061 (19)
C14—N14	1.477 (2)	C23—C24	1.373 (3)
N14—O42	1.219 (2)	C23—H23	0.93
N14—O41	1.219 (2)	C24—C25	1.375 (4)
C15—C16	1.387 (3)	C24—H24	0.93
C15—H15	0.93	C25—C26	1.378 (3)
C16—H16	0.93	C25—H25	0.93
C17—N17	1.272 (2)	C26—H26	0.93
C17—H17	0.93

C16—C11—C12	119.64 (17)	C17—N17—N27	111.12 (16)
C16—C11—C17	121.71 (17)	C27—N27—N17	112.75 (17)
C12—C11—C17	118.64 (17)	N27—C27—C21	120.69 (18)
C13—C12—C11	120.45 (18)	N27—C27—H27	119.7
C13—C12—H12	119.8	C21—C27—H27	119.7
C11—C12—H12	119.8	C22—C21—C26	117.68 (17)
C14—C13—C12	117.97 (18)	C22—C21—C27	122.81 (17)
C14—C13—H13	121.0	C26—C21—C27	119.50 (17)
C12—C13—H13	121.0	C23—C22—C21	120.49 (18)
C15—C14—C13	123.32 (17)	C23—C22—I22	116.93 (14)
C15—C14—N14	118.41 (17)	C21—C22—I22	122.53 (13)
C13—C14—N14	118.27 (18)	C24—C23—C22	120.43 (19)
O42—N14—O41	123.63 (18)	C24—C23—H23	119.8
O42—N14—C14	118.16 (17)	C22—C23—H23	119.8
O41—N14—C14	118.20 (18)	C23—C24—C25	120.08 (19)
C14—C15—C16	117.95 (19)	C23—C24—H24	120.0
C14—C15—H15	121.0	C25—C24—H24	120.0
C16—C15—H15	121.0	C24—C25—C26	119.9 (2)
C11—C16—C15	120.62 (19)	C24—C25—H25	120.1
C11—C16—H16	119.7	C26—C25—H25	120.1
C15—C16—H16	119.7	C25—C26—C21	121.41 (19)
N17—C17—C11	121.62 (18)	C25—C26—H26	119.3
N17—C17—H17	119.2	C21—C26—H26	119.3
C11—C17—H17	119.2

C17—N17—N27—C27	172.5 (2)	C12—C11—C16—C15	1.9 (4)
N27—N17—C17—C11	178.31 (19)	C17—C11—C16—C15	−177.2 (2)
N17—N27—C27—C21	178.14 (18)	C14—C15—C16—C11	−0.3 (4)
N17—C17—C11—C12	−175.3 (2)	C16—C11—C17—N17	3.8 (3)
N27—C27—C21—C22	173.5 (2)	N27—C27—C21—C26	−7.4 (3)
C13—C14—N14—O41	6.9 (3)	C26—C21—C22—C23	0.1 (3)
C16—C11—C12—C13	−1.5 (3)	C27—C21—C22—C23	179.2 (2)
C17—C11—C12—C13	177.6 (2)	C26—C21—C22—I22	177.59 (16)
C11—C12—C13—C14	−0.5 (3)	C27—C21—C22—I22	−3.3 (3)
C12—C13—C14—C15	2.2 (3)	C21—C22—C23—C24	0.5 (3)
C12—C13—C14—N14	−177.4 (2)	I22—C22—C23—C24	−177.22 (18)
C15—C14—N14—O42	6.2 (3)	C22—C23—C24—C25	−0.2 (4)
C13—C14—N14—O42	−174.18 (19)	C23—C24—C25—C26	−0.5 (4)
C15—C14—N14—O41	−172.7 (2)	C24—C25—C26—C21	1.0 (4)
C13—C14—C15—C16	−1.8 (4)	C22—C21—C26—C25	−0.8 (3)
N14—C14—C15—C16	177.8 (2)	C27—C21—C26—C25	−179.9 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C12—H12···O42ⁱ	0.93	2.58	3.430 (2)	153

Symmetry code: (i) x, y−1, z.

Experimental details

	(I)	(II)	(III)
Crystal data
Chemical formula	C₁₄H₁₀I_1.12N_2.88O_1.76	C₁₄H₁₀IN₃O₂	C₁₄H₁₀IN₃O₂
M_r	388.69	379.15	379.15
Crystal system, space group	Monoclinic, C2/c	Triclinic, P1	Monoclinic, C2/c
Temperature (K)	120	120	293
a, b, c (Å)	15.3033 (8), 3.7952 (3), 23.3097 (16)	7.2969 (3), 7.3235 (3), 13.7939 (6)	27.9470 (11), 8.0563 (3), 13.7464 (5)
α, β, γ (°)	90, 97.836 (4), 90	97.405 (2), 100.410 (2), 107.590 (3)	90, 117.425 (1), 90
V (Å³)	1341.16 (16)	677.73 (5)	2747.16 (18)
Z	4	2	8
Radiation type	Mo Kα	Mo Kα	Mo Kα
µ (mm⁻¹)	2.66	2.37	2.34
Crystal size (mm)	0.08 × 0.06 × 0.04	0.20 × 0.12 × 0.05	0.37 × 0.25 × 0.06

Data collection
Diffractometer	Nonius KappaCCD area-detector diffractometer	Nonius KappaCCD area-detector diffractometer	Bruker SMART 1000 CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2003)	Multi-scan (SADABS; Sheldrick, 2003)	Multi-scan (SADABS; Bruker, 2000)
T_min, T_max	0.815, 0.901	0.649, 0.891	0.479, 0.873
No. of measured, independent and observed [I > 2σ(I)] reflections	6403, 1482, 1156	13382, 3120, 2909	15927, 4956, 3759
R_int	0.066	0.029	0.024
(sin θ/λ)_max (Å⁻¹)	0.648	0.651	0.756

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.046, 0.100, 1.07	0.023, 0.085, 1.28	0.030, 0.079, 1.03
No. of reflections	1482	3120	4956
No. of parameters	104	181	181
No. of restraints	2	0	0
H-atom treatment	H-atom parameters constrained	H-atom parameters constrained	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.91, −0.82	1.06, −1.04	0.82, −0.77

Computer programs: COLLECT (Nonius, 1998), SMART (Bruker, 1998), DENZO (Otwinowski & Minor, 1997) and COLLECT, SAINT (Bruker, 2000), DENZO and COLLECT, OSCAIL (McArdle, 2003) and SHELXS97 (Sheldrick, 1997), OSCAIL and SHELXL97 (Sheldrick, 1997), PLATON (Spek, 2003), SHELXL97 and PRPKAPPA (Ferguson, 1999).

Selected torsion angles (º) for (I) top

N1ⁱ—N1—C7—C1	−179.5 (5)	C1—C2—N2—O21	−154.3 (7)
N1—C7—C1—C2	−165.9 (4)

Symmetry code: (i) −x+1, −y+1, −z+1.

Selected torsion angles (º) for (II) top

C17—N17—N27—C27	177.5 (3)	N17—C17—C11—C12	−8.9 (4)
N27—N17—C17—C11	−179.4 (3)	N27—C27—C21—C22	−171.0 (3)
N17—N27—C27—C21	−180.0 (3)	C12—C13—N13—O31	−5.3 (4)

Hydrogen-bond geometry (Å, º) for (II) top

D—H···A	D—H	H···A	D···A	D—H···A
C12—H12···I22ⁱ	0.95	3.04	3.972 (3)	168
C25—H25···O32ⁱⁱ	0.95	2.50	3.436 (4)	167
C27—H27···I22ⁱ	0.95	3.06	3.923 (3)	153

Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x+1, y, z+1.

Selected torsion angles (º) for (III) top

C17—N17—N27—C27	172.5 (2)	N17—C17—C11—C12	−175.3 (2)
N27—N17—C17—C11	178.31 (19)	N27—C27—C21—C22	173.5 (2)
N17—N27—C27—C21	178.14 (18)	C13—C14—N14—O41	6.9 (3)

Hydrogen-bond geometry (Å, º) for (III) top

D—H···A	D—H	H···A	D···A	D—H···A
C12—H12···O42ⁱ	0.93	2.58	3.430 (2)	153

Symmetry code: (i) x, y−1, z.

Acknowledgements

X-ray data for (I) and (II) were collected at the EPSRC X-ray Crystallographic Service, University of Southampton, England; the authors thank the staff for all their help and advice. X-ray data for (III) were collected at the University of Aberdeen; the authors thank the University of Aberdeen for funding the purchase of this instrument. JLW thanks CNPq and FAPERJ for financial support.

References

Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573. CrossRef CAS Web of Science Google Scholar
Bondi, A. (1964). J. Phys. Chem. 68, 441–451. CrossRef CAS Web of Science Google Scholar
Braga, D., Grepioni, F., Biradha, K., Pedireddi, V. R. & Desiraju, G. R. (1995). J. Am. Chem. Soc. 117, 3156–3166. CrossRef CAS Web of Science Google Scholar
Bruker (1998). SMART. Version 5.0. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Bruker (2000). SADABS (Version 2.03) and SAINT (Version 6.02a). Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Desiraju, G. R. & Steiner, T. (1999). The Weak Hydrogen Bond. Oxford University Press. Google Scholar
Ferguson, G. (1999). PRPKAPPA. University of Guelph, Canada. Google Scholar
Glidewell, C., Howie, R. A., Low, J. N., Skakle, J. M. S., Wardell, S. M. S. V. & Wardell, J. L. (2002). Acta Cryst. B58, 864–876. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Glidewell, C., Low, J. N., Skakle, J. M. S. & Wardell, J. L. (2003a). Acta Cryst. C59, o95–o97. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Glidewell, C., Low, J. N., Skakle, J. M. S. & Wardell, J. L. (2003b). Acta Cryst. C59, o98–o101. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Glidewell, C., Low, J. N., Skakle, J. M. S. & Wardell, J. L. (2004). Acta Cryst. C60, o19–o23. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Glidewell, C., Low, J. N., Skakle, J. M. S., Wardell, S. M. S. V. & Wardell, J. L. (2002). Acta Cryst. C58, o487–o490. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Glidewell, C., Low, J. N., Skakle, J. M. S., Wardell, S. M. S. V. & Wardell, J. L. (2004). Acta Cryst. B60, 472–480. Web of Science CSD CrossRef IUCr Journals Google Scholar
Kelly, C. J., Skakle, J. M. S., Wardell, J. L., Wardell, S. M. S. V., Low, J. N. & Glidewell, C. (2002). Acta Cryst. B58, 94–108. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
McArdle, P. (2003). OSCAIL for Windows. Version 10. Crystallography Centre, Chemistry Department, NUI Galway, Ireland. Google Scholar
Nonius (1998). COLLECT. Nonius BV, Delft, The Netherlands. Google Scholar
Nyburg, S. C. & Faerman, C. H. (1985). Acta Cryst. B41, 274–279. CrossRef CAS Web of Science IUCr Journals Google Scholar
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. Google Scholar
Ramasubbu, N., Parthasarathy, R. & Murray-Rust, P. (1986). J. Am. Chem. Soc. 108, 4308–4314. CrossRef CAS Web of Science Google Scholar
Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2003). SADABS. Version 2.10. University of Göttingen, Germany. Google Scholar
Spek, A. L. (2003). J. Appl. Cryst. 36, 7–13. Web of Science CrossRef CAS IUCr Journals Google Scholar
Starbuck, J., Norman, N. C. & Orpen, A. G. (1999). New J. Chem. 23, 969–972. Web of Science CrossRef Google Scholar
Wardell, J. L., Wardell, S. M. S. V., Skakle, J. M. S., Low, J. N. & Glidewell, C. (2002). Acta Cryst. C58, o428–o430. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar

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ISSN: 2053-2296

Volume 61| Part 5| May 2005| Pages o312-o316

doi:10.1107/S0108270105009248

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

Supramolecular structures of three isomeric (E,E)-1-(2-iodo­phenyl)-4-(nitro­phenyl)-2,3-di­aza-1,3-butadienes: changes in inter­molecular inter­actions consequent upon changes of substituent location

Comment

Experimental

Compound (I)

Crystal data

Data collection

Refinement

Compound (II)

Crystal data

Data collection

Refinement

Compound (III)

Crystal data

Data collection

Refinement

Supporting information

Acknowledgements

References

organic compounds

Supramolecular structures of three isomeric (E,E)-1-(2-iodophenyl)-4-(nitrophenyl)-2,3-diaza-1,3-butadienes: changes in intermolecular interactions consequent upon changes of substituent location