Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270110033561/fa3235sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270110033561/fa3235Isup2.hkl |
CCDC reference: 726080
The H2SSC ligand was prepared by reaction of semicarbazide hydrochloride with salicyl aldehyde in a molar ratio of 1:1 in water. Analysis calculated for H2SSC: C 53.63, H 5.06, N 23.45%; found: C 53.74, H 5.065, N 22.97%. Spectroscopic analysis: IR (KBr): ν(OH) 3472 cm-1, ν(C═O) 1697 cm-1, ν(C═N) 1622 cm-1, ν (C—O) 1267 cm-1.
H2SSC (0.179 g, 1 mmol) and ZnCl2 (0.136 g, 1 mmol) were dissolved in separate methanol solutions (20 ml). These solutions were mixed in a flask and stirred for ~3 h. A milky white precipitate was obtained from the resulting reaction solution, separated by filtration, washed with methanol and tetrahydrofuran, and dried. The filtrate was allowed to stand at room temperature and colourless single crystals of (I) were grown by slow evaporation over a period of about four weeks. Analysis calculated for Zn(HSSC)Cl: C 34.44, H 2.89, N 15.06%; found: C 34.32, H 2.91, N 15.02%. Spectroscopic analysis: IR (KBr): ν (C═O) 1665 cm-1, ν(C═N) 1600 cm-1, ν(C—O) 1275 cm-1.
H atoms attached to C, N and O atoms were placed in geometrically idealized positions, with C—H(CH) = 0.93, C—H(CH3) = 0.96, N—H = 0.86 and O—H = 0.82 Å, and with Uiso(H) = 1.2Ueq(C,N) or 1.5Ueq(CH2).
Data collection: SMART (Bruker, 1999); cell refinement: SMART (Bruker, 1999); data reduction: SHELXTL (Sheldrick, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2004); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).
[Zn2(C8H8N3O2)Cl2]·2CH4O | Z = 1 |
Mr = 622.07 | F(000) = 316 |
Triclinic, P1 | Dx = 1.632 Mg m−3 |
a = 6.9061 (8) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 8.3585 (12) Å | Cell parameters from 1243 reflections |
c = 11.7666 (16) Å | θ = 2.6–23.5° |
α = 75.066 (1)° | µ = 2.15 mm−1 |
β = 80.565 (2)° | T = 298 K |
γ = 76.003 (1)° | Lamellar, colourless |
V = 633.04 (15) Å3 | 0.38 × 0.20 × 0.10 mm |
Bruker SMART CCD area-detector diffractometer | 2179 independent reflections |
Radiation source: fine-focus sealed tube | 1602 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.051 |
ϕ and ω scans | θmax = 25.0°, θmin = 1.8° |
Absorption correction: multi-scan (SADABS; Sheldrick, 2001) | h = −8→8 |
Tmin = 0.496, Tmax = 0.814 | k = −9→7 |
3291 measured reflections | l = −13→13 |
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)] = 0.057 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.146 | H-atom parameters constrained |
S = 1.04 | w = 1/[σ2(Fo2) + (0.0794P)2] where P = (Fo2 + 2Fc2)/3 |
2179 reflections | (Δ/σ)max = 0.002 |
155 parameters | Δρmax = 0.78 e Å−3 |
0 restraints | Δρmin = −0.77 e Å−3 |
[Zn2(C8H8N3O2)Cl2]·2CH4O | γ = 76.003 (1)° |
Mr = 622.07 | V = 633.04 (15) Å3 |
Triclinic, P1 | Z = 1 |
a = 6.9061 (8) Å | Mo Kα radiation |
b = 8.3585 (12) Å | µ = 2.15 mm−1 |
c = 11.7666 (16) Å | T = 298 K |
α = 75.066 (1)° | 0.38 × 0.20 × 0.10 mm |
β = 80.565 (2)° |
Bruker SMART CCD area-detector diffractometer | 2179 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 2001) | 1602 reflections with I > 2σ(I) |
Tmin = 0.496, Tmax = 0.814 | Rint = 0.051 |
3291 measured reflections |
R[F2 > 2σ(F2)] = 0.057 | 0 restraints |
wR(F2) = 0.146 | H-atom parameters constrained |
S = 1.04 | Δρmax = 0.78 e Å−3 |
2179 reflections | Δρmin = −0.77 e Å−3 |
155 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
Zn1 | 0.41340 (9) | 0.60071 (9) | 0.38095 (6) | 0.0428 (3) | |
Cl1 | 0.5605 (2) | 0.8190 (2) | 0.28316 (16) | 0.0576 (5) | |
N1 | 0.0202 (7) | 0.6473 (6) | 0.3053 (4) | 0.0461 (12) | |
H1 | −0.1070 | 0.6756 | 0.3005 | 0.055* | |
N2 | 0.1024 (6) | 0.6628 (6) | 0.4013 (4) | 0.0411 (11) | |
N3 | 0.0729 (8) | 0.5758 (7) | 0.1254 (4) | 0.0581 (14) | |
H3A | 0.1496 | 0.5368 | 0.0690 | 0.070* | |
H3B | −0.0543 | 0.6088 | 0.1212 | 0.070* | |
O1 | 0.3340 (5) | 0.5394 (5) | 0.2306 (3) | 0.0450 (10) | |
O2 | 0.3840 (5) | 0.6067 (5) | 0.5588 (3) | 0.0486 (10) | |
O3 | 0.3335 (7) | 0.4008 (6) | −0.0475 (4) | 0.0659 (13) | |
H3 | 0.4146 | 0.4395 | −0.1002 | 0.099* | |
C1 | 0.1512 (8) | 0.5852 (7) | 0.2194 (5) | 0.0422 (13) | |
C2 | −0.0167 (8) | 0.7331 (7) | 0.4792 (5) | 0.0435 (14) | |
H2 | −0.1525 | 0.7658 | 0.4689 | 0.052* | |
C3 | 0.0452 (8) | 0.7645 (7) | 0.5813 (5) | 0.0399 (13) | |
C4 | 0.2431 (8) | 0.7066 (7) | 0.6158 (5) | 0.0405 (13) | |
C5 | 0.2845 (9) | 0.7595 (8) | 0.7099 (5) | 0.0504 (15) | |
H5 | 0.4142 | 0.7266 | 0.7318 | 0.060* | |
C6 | 0.1376 (9) | 0.8606 (8) | 0.7729 (6) | 0.0560 (16) | |
H6 | 0.1698 | 0.8920 | 0.8366 | 0.067* | |
C7 | −0.0565 (10) | 0.9141 (8) | 0.7404 (6) | 0.0557 (16) | |
H7 | −0.1550 | 0.9814 | 0.7819 | 0.067* | |
C8 | −0.0997 (9) | 0.8665 (7) | 0.6470 (5) | 0.0495 (15) | |
H8 | −0.2296 | 0.9023 | 0.6255 | 0.059* | |
C9 | 0.4273 (14) | 0.2413 (11) | 0.0164 (7) | 0.097 (3) | |
H9A | 0.5704 | 0.2300 | 0.0024 | 0.145* | |
H9B | 0.3902 | 0.1536 | −0.0091 | 0.145* | |
H9C | 0.3853 | 0.2316 | 0.0993 | 0.145* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Zn1 | 0.0242 (4) | 0.0549 (5) | 0.0449 (4) | 0.0024 (3) | −0.0063 (3) | −0.0121 (3) |
Cl1 | 0.0300 (8) | 0.0599 (10) | 0.0780 (11) | −0.0054 (7) | −0.0076 (7) | −0.0098 (8) |
N1 | 0.026 (2) | 0.061 (3) | 0.053 (3) | −0.001 (2) | −0.013 (2) | −0.019 (2) |
N2 | 0.029 (2) | 0.051 (3) | 0.040 (3) | −0.004 (2) | −0.004 (2) | −0.009 (2) |
N3 | 0.037 (3) | 0.091 (4) | 0.051 (3) | −0.003 (3) | −0.011 (2) | −0.030 (3) |
O1 | 0.023 (2) | 0.062 (3) | 0.050 (2) | −0.0021 (18) | −0.0090 (17) | −0.0159 (19) |
O2 | 0.032 (2) | 0.062 (3) | 0.041 (2) | 0.0190 (19) | −0.0119 (17) | −0.0155 (19) |
O3 | 0.052 (3) | 0.081 (3) | 0.056 (3) | −0.006 (2) | 0.007 (2) | −0.016 (2) |
C1 | 0.031 (3) | 0.046 (3) | 0.048 (3) | −0.011 (3) | −0.001 (3) | −0.008 (3) |
C2 | 0.023 (3) | 0.047 (3) | 0.055 (4) | 0.000 (2) | −0.006 (3) | −0.008 (3) |
C3 | 0.035 (3) | 0.039 (3) | 0.039 (3) | 0.001 (2) | −0.001 (2) | −0.005 (2) |
C4 | 0.033 (3) | 0.038 (3) | 0.041 (3) | 0.007 (2) | −0.005 (2) | −0.007 (2) |
C5 | 0.039 (3) | 0.056 (4) | 0.056 (4) | 0.005 (3) | −0.013 (3) | −0.021 (3) |
C6 | 0.051 (4) | 0.062 (4) | 0.054 (4) | 0.001 (3) | −0.003 (3) | −0.025 (3) |
C7 | 0.053 (4) | 0.047 (4) | 0.058 (4) | 0.006 (3) | 0.008 (3) | −0.019 (3) |
C8 | 0.032 (3) | 0.054 (4) | 0.054 (4) | 0.003 (3) | 0.006 (3) | −0.014 (3) |
C9 | 0.098 (7) | 0.091 (6) | 0.076 (6) | −0.006 (5) | 0.009 (5) | 0.000 (5) |
Zn1—O2i | 1.996 (4) | O3—H3 | 0.8200 |
Zn1—N2 | 2.072 (4) | C2—C3 | 1.442 (8) |
Zn1—O2 | 2.081 (4) | C2—H2 | 0.9300 |
Zn1—O1 | 2.148 (4) | C3—C8 | 1.414 (7) |
Zn1—Cl1 | 2.2616 (18) | C3—C4 | 1.424 (7) |
Zn1—Zn1i | 3.1317 (13) | C4—C5 | 1.386 (8) |
C1—N1 | 1.362 (7) | C5—C6 | 1.398 (8) |
N1—N2 | 1.391 (6) | C5—H5 | 0.9300 |
N1—H1 | 0.8600 | C6—C7 | 1.390 (8) |
C2—N2 | 1.288 (7) | C6—H6 | 0.9300 |
C1—N3 | 1.336 (7) | C7—C8 | 1.359 (8) |
N3—H3A | 0.8600 | C7—H7 | 0.9300 |
N3—H3B | 0.8600 | C8—H8 | 0.9300 |
C1—O1 | 1.246 (6) | C9—H9A | 0.9600 |
O2—C4 | 1.333 (6) | C9—H9B | 0.9600 |
O2—Zn1i | 1.996 (4) | C9—H9C | 0.9600 |
O3—C9 | 1.410 (9) | ||
O2i—Zn1—N2 | 133.86 (19) | O1—C1—N1 | 120.4 (5) |
O2i—Zn1—O2 | 79.66 (16) | N3—C1—N1 | 116.6 (5) |
N2—Zn1—O2 | 84.02 (16) | N2—C2—C3 | 124.7 (5) |
O2i—Zn1—O1 | 101.43 (15) | N2—C2—H2 | 117.6 |
N2—Zn1—O1 | 76.77 (15) | C3—C2—H2 | 117.6 |
O2—Zn1—O1 | 154.22 (16) | C8—C3—C4 | 118.7 (5) |
O2i—Zn1—Cl1 | 111.63 (13) | C8—C3—C2 | 116.9 (5) |
N2—Zn1—Cl1 | 114.26 (13) | C4—C3—C2 | 124.3 (5) |
O2—Zn1—Cl1 | 105.34 (13) | O2—C4—C5 | 121.2 (5) |
O1—Zn1—Cl1 | 98.22 (12) | O2—C4—C3 | 121.2 (5) |
O2i—Zn1—Zn1i | 40.82 (11) | C5—C4—C3 | 117.6 (5) |
N2—Zn1—Zn1i | 111.86 (13) | C4—C5—C6 | 122.1 (5) |
O2—Zn1—Zn1i | 38.83 (10) | C4—C5—H5 | 118.9 |
O1—Zn1—Zn1i | 136.45 (11) | C6—C5—H5 | 118.9 |
Cl1—Zn1—Zn1i | 114.25 (5) | C7—C6—C5 | 120.1 (6) |
C1—N1—N2 | 116.6 (4) | C7—C6—H6 | 120.0 |
C1—N1—H1 | 121.7 | C5—C6—H6 | 120.0 |
N2—N1—H1 | 121.7 | C8—C7—C6 | 118.8 (5) |
C2—N2—N1 | 117.7 (4) | C8—C7—H7 | 120.6 |
C2—N2—Zn1 | 129.2 (4) | C6—C7—H7 | 120.6 |
N1—N2—Zn1 | 112.3 (3) | C7—C8—C3 | 122.6 (5) |
C1—N3—H3A | 120.0 | C7—C8—H8 | 118.7 |
C1—N3—H3B | 120.0 | C3—C8—H8 | 118.7 |
H3A—N3—H3B | 120.0 | O3—C9—H9A | 109.5 |
C1—O1—Zn1 | 113.2 (3) | O3—C9—H9B | 109.5 |
C4—O2—Zn1i | 131.1 (3) | H9A—C9—H9B | 109.5 |
C4—O2—Zn1 | 127.6 (3) | O3—C9—H9C | 109.5 |
Zn1i—O2—Zn1 | 100.34 (16) | H9A—C9—H9C | 109.5 |
C9—O3—H3 | 109.5 | H9B—C9—H9C | 109.5 |
O1—C1—N3 | 123.0 (5) | ||
C1—N1—N2—C2 | 174.9 (5) | Cl1—Zn1—O2—Zn1i | −109.78 (15) |
C1—N1—N2—Zn1 | 4.1 (6) | Zn1—O1—C1—N3 | 172.7 (4) |
O2i—Zn1—N2—C2 | 91.5 (5) | Zn1—O1—C1—N1 | −7.7 (6) |
O2—Zn1—N2—C2 | 22.0 (5) | N2—N1—C1—O1 | 2.6 (8) |
O1—Zn1—N2—C2 | −175.3 (5) | N2—N1—C1—N3 | −177.8 (5) |
Cl1—Zn1—N2—C2 | −82.1 (5) | N1—N2—C2—C3 | −177.6 (5) |
Zn1i—Zn1—N2—C2 | 49.7 (5) | Zn1—N2—C2—C3 | −8.6 (8) |
O2i—Zn1—N2—N1 | −99.0 (4) | N2—C2—C3—C8 | 170.2 (5) |
O2—Zn1—N2—N1 | −168.5 (4) | N2—C2—C3—C4 | −6.7 (9) |
O1—Zn1—N2—N1 | −5.8 (3) | Zn1i—O2—C4—C5 | 44.8 (8) |
Cl1—Zn1—N2—N1 | 87.4 (3) | Zn1—O2—C4—C5 | −148.4 (5) |
Zn1i—Zn1—N2—N1 | −140.8 (3) | Zn1i—O2—C4—C3 | −136.0 (5) |
O2i—Zn1—O1—C1 | 140.1 (4) | Zn1—O2—C4—C3 | 30.9 (8) |
N2—Zn1—O1—C1 | 7.4 (4) | C8—C3—C4—O2 | 178.3 (5) |
O2—Zn1—O1—C1 | 50.2 (5) | C2—C3—C4—O2 | −4.9 (9) |
Cl1—Zn1—O1—C1 | −105.8 (4) | C8—C3—C4—C5 | −2.4 (8) |
Zn1i—Zn1—O1—C1 | 115.3 (4) | C2—C3—C4—C5 | 174.4 (6) |
O2i—Zn1—O2—C4 | −170.0 (6) | O2—C4—C5—C6 | −178.3 (6) |
N2—Zn1—O2—C4 | −33.3 (5) | C3—C4—C5—C6 | 2.5 (9) |
O1—Zn1—O2—C4 | −75.1 (6) | C4—C5—C6—C7 | −1.3 (10) |
Cl1—Zn1—O2—C4 | 80.3 (5) | C5—C6—C7—C8 | 0.0 (10) |
Zn1i—Zn1—O2—C4 | −170.0 (6) | C6—C7—C8—C3 | −0.1 (9) |
O2i—Zn1—O2—Zn1i | 0.0 | C4—C3—C8—C7 | 1.3 (9) |
N2—Zn1—O2—Zn1i | 136.7 (2) | C2—C3—C8—C7 | −175.8 (6) |
O1—Zn1—O2—Zn1i | 94.9 (3) |
Symmetry code: (i) −x+1, −y+1, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3A···O3 | 0.86 | 2.08 | 2.929 (7) | 170 |
N3—H3B···O3ii | 0.86 | 2.27 | 3.040 (8) | 150 |
O3—H3···O1iii | 0.82 | 2.13 | 2.923 (6) | 163 |
N1—H1···Cl1iv | 0.86 | 2.33 | 3.175 (5) | 166 |
Symmetry codes: (ii) −x, −y+1, −z; (iii) −x+1, −y+1, −z; (iv) x−1, y, z. |
Experimental details
Crystal data | |
Chemical formula | [Zn2(C8H8N3O2)Cl2]·2CH4O |
Mr | 622.07 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 298 |
a, b, c (Å) | 6.9061 (8), 8.3585 (12), 11.7666 (16) |
α, β, γ (°) | 75.066 (1), 80.565 (2), 76.003 (1) |
V (Å3) | 633.04 (15) |
Z | 1 |
Radiation type | Mo Kα |
µ (mm−1) | 2.15 |
Crystal size (mm) | 0.38 × 0.20 × 0.10 |
Data collection | |
Diffractometer | Bruker SMART CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 2001) |
Tmin, Tmax | 0.496, 0.814 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3291, 2179, 1602 |
Rint | 0.051 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.057, 0.146, 1.04 |
No. of reflections | 2179 |
No. of parameters | 155 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.78, −0.77 |
Computer programs: SMART (Bruker, 1999), SHELXTL (Sheldrick, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 2004).
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3A···O3 | 0.86 | 2.078 | 2.929 (7) | 169.89 |
N3—H3B···O3i | 0.86 | 2.266 | 3.040 (8) | 149.66 |
O3—H3···O1ii | 0.82 | 2.130 | 2.923 (6) | 162.56 |
N1—H1···Cl1iii | 0.86 | 2.334 | 3.175 (5) | 165.9 |
Symmetry codes: (i) −x, −y+1, −z; (ii) −x+1, −y+1, −z; (iii) x−1, y, z. |
In the past decade, coordination-driven and conventional hydrogen-bonding directed self-assembly of high-symmetry conglomerates has been studied extensively (Wei et al., 2009). Noncovalent interactions have also been recognized to play a substantial role in a variety of chemical and biological phenomena (Nishio, 2004). The understanding and utilization of all types of non-covalent interactions including π–π stacking is of fundamental importance for the further development of supramolecular chemistry and the study and prediction of crystal structures (Janiak, 2000). Dance & Scudder (1995) suggested the concept of `molecular embrace', based on phenyl–phenyl intermolecular interactions, and developed the embrace paradigm as an important and widespread intermolecular motif and crystal engineering tool by analysing the packing of molecules in crystals (Dance & Scudder, 2009). Varied hydrogen-bond patterns including traditional and nonclassical versions have been observed in crystal packing, giving diverse supramolecular motifs (Casas et al., 2004). Aullón et al. (1998) conducted a study based on the Cambridge Structural Database (Allen, 2002) involving hydrogen bonds containing M—Cl (M = transition metal), C—Cl or Cl- and either HO or HN. The results indicated that M—Cl moieties are good anisotropic hydrogen-bond acceptors. The D—H···Cl—M (D = O or N) contacts were categorized as short (H···Cl ≤ 2.52 Å), intermediate (2.52–2.95 Å) and long 2.95–3.15 Å. It was reported that M—Cl in complexes has the potential to interact with hydrogen-bond donors in both a strong (i.e. short) and an anisotropic fashion. To the best of our knowledge, non-aromatic–aromatic π–π stacking has rarely been reported. In this work, the synthesis and structural characterization of the title dinuclear ZnII complex, (I), containing nonclassical N—H···Cl—ZnII hydrogen bonding and π–π interactions that involve non-aromatic groups, are discussed.
Compound (I) is composed of centrosymmetric [Zn(HSSC)Cl]2 dimers {HSSC is 2-[(2-carbamoylhydrazin-1-ylidene)methyl]phenolate} (Fig. 1). Each HSSC- ligand has a deprotonated phenol group, forms a one-atom bridge between the two ZnII centres and coordinates to one ZnII ion through its N2 and O1 atoms. The Zn1···Zn1(-x + 1, -y + 1, -z + 1) distance is 3.1317 (13) Å. Atom Zn1 has a square-pyramidal coordination environment and is situated slightly above the basal plane, which is formed by atoms N2 from azomethine (–CH═N–), O1 from ureido (–NH—CO—NH2) and O2 and O2(-x + 1, -y + 1, -z + 1) from different phenol groups, with the axial position occupied by one Cl- ion (Fig. 1). The Zn—O(N,Cl) distances and related angles are all within expected ranges [Standard reference?]. However, the structure of the HSSC- ligand is slightly twisted, with an angle of 13.5 (3)° between the ureido plane (C1/O1/N1/N3) and the benzene group (C3–C8) to accommodate the geometric requirements of coordination about ZnII, and to accommodate noncovalent interactions.
The π-electron density is delocalized in neutral H2SSC, especially when an aromatic group is bound to the azomethine C atom (Casas et al., 2000). Compared with free H2SSC, the related bond lengths of the C2—N2—N1—C1—O1—N3 backbone are almost unvaried in the dimer of (I) (Table 1). In addition, compared with conventional localized bond lengths of C—N = 1.472 (5) Å in RNH2, N—N = 1.451 (5) Å in R2NNH2 and C═O = 1.145 (10) Å in carbonyls (Dean 1999), the corresponding single bonds are shorter and the double bonds are longer in (I). Thus, it is reasonable to conclude that HSSC- maintains a considerably delocalized π system in the dimer of (I).
The dimers of (I) are assembled through intermolecular N1—H1···Cl1(x-1, y, z) interactions (H···Cl = 2.334 Å and N—H···Cl = 165.9°) and non-aromatic–aromatic π–π interactions to form an infinite one-dimensional hydrogen-bond-supported chain. The one-dimensional chain has the form of a staircase propagating in the direction of the shortest lattice parameter (a axis; Fig. 2a). According to the study of Aullón et al. (1998), the H1···Cl1(x - 1, y, z) distance of 2.334 Å indicates strong hydrogen-bonding interactions in the one-dimensional chains. Within one staircase-like chain, the HSSC- ligand is in contact with that at (-x, -y + 1, -z + 1) in a head-to-tail fashion, with π–π interactions that appear to extend the entire length of the ligand (Fig. 2b). Specifically, non-aromatic ureido and azomethine and aromatic phenol groups participate in π-stacking. The best planes of the two contacting ligands are parallel, being related by a centre of symmetry, and are at a distance of 3.618 (7) Å.
The one-dimensional chains pack into two-dimensional sheets in which neighbouring chains are related by a b-axis translation (Fig. 3). Between adjacent chains there are van der Waals contacts between HSSC groups, but their relative disposition is substantially slipped so that no π–π interaction exists.
More substantially, the one-dimensional chains stack in a side-by-side fashion along the c axis to form two-dimensional sheets of parallel staircases, which are held together through hydrogen bonds to form aggregates, the basic units of which lie parallel to (010) (Fig. 4). Hydrogen bonding mediates the formation of a chain of fused rings parallel to the a axis of the unit cell, with alternating R44(12) and R42(8) rings [see Bernstein et al. (1995) for hydrogen-bonding motifs]. These hydrogen-bonded rings also involve the methanol molecules (Table 2).