Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270104019821/ob1195sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270104019821/ob1195Isup2.hkl |
CCDC reference: 254902
The title compound was obtained by direct mixing of equimolar (0.025 M) aqueous ZnSO4·7H2O and methanolic 2,4,6-tris(2-pyridyl)-1,3,5-triazine (tpt) solutions. After a few days, some crystalline material precipitated, but it was found to be unsuitable for X-ray diffraction. This material was therefore dissolved in water and heated at 378 K for 2 h in a pressurized reactor. Slow evaporation of this solution resulted in the formation of some colourless prismatic crystals of (I), which were suitable for X-ray analysis.
H atoms attached to C atomswere included in their calculated positions, with C—H distances of 0.93 Å, and allowed to ride, with Uiso(H) = 1.2Ueq(C). Please check added text. The water H atoms were located from difference Fourier syntheses and refined with restrained O—H and H···H distances of 0.82 (1) and 1.30 (2) Å, respectively.
Data collection: MSC/AFC Diffractometer Control Software (Molecular Structure Corporation, 1988); cell refinement: MSC/AFC Diffractometer Control Software; data reduction: SHELXTL/PC (Sheldrick, 1994); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP in SHELXTL/PC; software used to prepare material for publication: SHELXL97.
[Zn(SO4)(C18H12N6)(H2O)2]·2H2O | Z = 2 |
Mr = 545.83 | F(000) = 560 |
Triclinic, P1 | Dx = 1.700 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 7.7120 (15) Å | Cell parameters from 25 reflections |
b = 11.771 (2) Å | θ = 7.5–12.5° |
c = 12.523 (3) Å | µ = 1.31 mm−1 |
α = 85.27 (3)° | T = 293 K |
β = 75.38 (3)° | Prism, colourless |
γ = 75.82 (3)° | 0.32 × 0.12 × 0.12 mm |
V = 1066.2 (4) Å3 |
Rigaku AFC-6S diffractometer | 2117 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.076 |
Graphite monochromator | θmax = 27.1°, θmin = 1.7° |
ω/2θ scans | h = −9→9 |
Absorption correction: ψ scan (North et al., 1968) | k = −14→15 |
Tmin = 0.78, Tmax = 0.85 | l = 0→15 |
5725 measured reflections | 3 standard reflections every 150 reflections |
4670 independent reflections | intensity decay: <2% |
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)] = 0.058 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.140 | H atoms treated by a mixture of independent and constrained refinement |
S = 0.92 | w = 1/[σ2(Fo2) + (0.0697P)2] where P = (Fo2 + 2Fc2)/3 |
4670 reflections | (Δ/σ)max = 0.014 |
336 parameters | Δρmax = 0.90 e Å−3 |
18 restraints | Δρmin = −1.00 e Å−3 |
[Zn(SO4)(C18H12N6)(H2O)2]·2H2O | γ = 75.82 (3)° |
Mr = 545.83 | V = 1066.2 (4) Å3 |
Triclinic, P1 | Z = 2 |
a = 7.7120 (15) Å | Mo Kα radiation |
b = 11.771 (2) Å | µ = 1.31 mm−1 |
c = 12.523 (3) Å | T = 293 K |
α = 85.27 (3)° | 0.32 × 0.12 × 0.12 mm |
β = 75.38 (3)° |
Rigaku AFC-6S diffractometer | 2117 reflections with I > 2σ(I) |
Absorption correction: ψ scan (North et al., 1968) | Rint = 0.076 |
Tmin = 0.78, Tmax = 0.85 | 3 standard reflections every 150 reflections |
5725 measured reflections | intensity decay: <2% |
4670 independent reflections |
R[F2 > 2σ(F2)] = 0.058 | 18 restraints |
wR(F2) = 0.140 | H atoms treated by a mixture of independent and constrained refinement |
S = 0.92 | Δρmax = 0.90 e Å−3 |
4670 reflections | Δρmin = −1.00 e Å−3 |
336 parameters |
x | y | z | Uiso*/Ueq | ||
Zn | 0.43870 (11) | 0.25352 (6) | 0.22993 (6) | 0.0333 (2) | |
S | 0.8222 (2) | 0.18460 (11) | 0.31375 (12) | 0.0329 (4) | |
O1 | 0.6709 (5) | 0.1558 (3) | 0.2765 (3) | 0.0372 (10) | |
O2 | 0.8625 (6) | 0.2949 (3) | 0.2610 (3) | 0.0421 (11) | |
O3 | 0.7713 (7) | 0.1986 (4) | 0.4363 (3) | 0.0555 (13) | |
O4 | 0.9891 (6) | 0.0891 (3) | 0.2813 (3) | 0.0470 (11) | |
N1 | 0.5972 (6) | 0.2460 (4) | 0.0502 (4) | 0.0330 (12) | |
N2 | 0.5250 (6) | 0.4088 (3) | 0.1935 (3) | 0.0224 (10) | |
N3 | 0.3277 (6) | 0.3528 (3) | 0.3827 (4) | 0.0315 (12) | |
N4 | 0.7050 (7) | 0.5254 (4) | 0.0741 (4) | 0.0353 (12) | |
N5 | 0.5491 (7) | 0.5848 (4) | 0.2597 (4) | 0.0382 (12) | |
N6 | 0.8074 (7) | 0.7348 (4) | 0.0321 (4) | 0.0412 (13) | |
C1 | 0.6251 (8) | 0.1633 (5) | −0.0203 (5) | 0.0386 (15) | |
H1 | 0.5776 | 0.0979 | 0.0046 | 0.046* | |
C2 | 0.7237 (9) | 0.1674 (5) | −0.1324 (5) | 0.0487 (18) | |
H2 | 0.7373 | 0.1085 | −0.1812 | 0.058* | |
C3 | 0.7976 (8) | 0.2636 (5) | −0.1647 (5) | 0.0438 (17) | |
H3 | 0.8664 | 0.2689 | −0.2367 | 0.053* | |
C4 | 0.7726 (9) | 0.3511 (5) | −0.0938 (4) | 0.0373 (16) | |
H4 | 0.8211 | 0.4165 | −0.1168 | 0.045* | |
C5 | 0.6736 (7) | 0.3399 (4) | 0.0127 (4) | 0.0307 (14) | |
C6 | 0.6345 (7) | 0.4303 (4) | 0.0952 (4) | 0.0271 (13) | |
C7 | 0.6551 (8) | 0.6005 (4) | 0.1574 (4) | 0.0290 (13) | |
C8 | 0.4868 (8) | 0.4872 (4) | 0.2713 (4) | 0.0279 (13) | |
C9 | 0.3648 (8) | 0.4609 (5) | 0.3807 (4) | 0.0306 (13) | |
C10 | 0.3048 (9) | 0.5381 (5) | 0.4632 (5) | 0.0352 (14) | |
H10 | 0.3359 | 0.6103 | 0.4552 | 0.042* | |
C11 | 0.1922 (8) | 0.5042 (6) | 0.5624 (5) | 0.0446 (16) | |
H11 | 0.1445 | 0.5541 | 0.6220 | 0.054* | |
C12 | 0.1559 (9) | 0.3956 (5) | 0.5675 (5) | 0.0464 (17) | |
H12 | 0.0859 | 0.3703 | 0.6329 | 0.056* | |
C13 | 0.2202 (9) | 0.3226 (5) | 0.4785 (5) | 0.0432 (16) | |
H13 | 0.1887 | 0.2506 | 0.4845 | 0.052* | |
C14 | 0.7199 (8) | 0.7090 (4) | 0.1370 (5) | 0.0381 (16) | |
C15 | 0.6871 (8) | 0.7848 (5) | 0.2226 (5) | 0.0408 (16) | |
H15 | 0.6269 | 0.7655 | 0.2935 | 0.049* | |
C16 | 0.7439 (10) | 0.8901 (5) | 0.2030 (6) | 0.0513 (18) | |
H16 | 0.7207 | 0.9424 | 0.2594 | 0.062* | |
C17 | 0.8346 (9) | 0.9132 (5) | 0.0981 (5) | 0.0455 (17) | |
H17 | 0.8789 | 0.9810 | 0.0823 | 0.055* | |
C18 | 0.8604 (9) | 0.8363 (5) | 0.0158 (6) | 0.0483 (17) | |
H18 | 0.9181 | 0.8559 | −0.0555 | 0.058* | |
O1W | 0.3363 (6) | 0.1087 (3) | 0.2578 (3) | 0.0462 (11) | |
H1WA | 0.392 (4) | 0.0627 (16) | 0.297 (3) | 0.025 (16)* | |
H1WB | 0.2288 (16) | 0.1266 (12) | 0.293 (3) | 0.030* | |
O2W | 0.1957 (6) | 0.3441 (3) | 0.1763 (3) | 0.0442 (11) | |
H2WB | 0.213 (3) | 0.325 (3) | 0.1122 (11) | 0.053* | |
H2WA | 0.1127 (17) | 0.314 (3) | 0.211 (3) | 0.053* | |
O3W | 1.0003 (9) | 0.1261 (5) | 0.5924 (4) | 0.0720 (16) | |
H3WA | 0.898 (3) | 0.154 (4) | 0.581 (3) | 0.08 (3)* | |
H3WB | 1.012 (8) | 0.0549 (7) | 0.593 (4) | 0.15 (4)* | |
O4W | 0.3851 (14) | −0.0249 (8) | 0.4424 (7) | 0.110 (2) | |
H4WB | 0.296 (11) | 0.015 (7) | 0.485 (9) | 0.15 (4)* | |
H4WA | 0.367 (12) | −0.091 (3) | 0.450 (8) | 0.14 (4)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Zn | 0.0419 (5) | 0.0253 (3) | 0.0273 (4) | −0.0143 (3) | 0.0053 (3) | 0.0080 (3) |
S | 0.0335 (9) | 0.0264 (7) | 0.0360 (9) | −0.0100 (7) | −0.0036 (7) | 0.0103 (6) |
O1 | 0.031 (2) | 0.035 (2) | 0.039 (2) | −0.0061 (18) | −0.002 (2) | 0.0135 (18) |
O2 | 0.048 (3) | 0.0307 (19) | 0.048 (2) | −0.0271 (19) | 0.001 (2) | 0.0152 (18) |
O3 | 0.078 (4) | 0.063 (3) | 0.027 (2) | −0.032 (3) | −0.004 (2) | 0.007 (2) |
O4 | 0.035 (3) | 0.035 (2) | 0.063 (3) | −0.0104 (19) | 0.001 (2) | 0.016 (2) |
N1 | 0.035 (3) | 0.023 (2) | 0.033 (3) | −0.003 (2) | 0.002 (2) | 0.004 (2) |
N2 | 0.024 (3) | 0.026 (2) | 0.019 (2) | −0.0093 (19) | −0.006 (2) | −0.0010 (18) |
N3 | 0.030 (3) | 0.023 (2) | 0.037 (3) | −0.014 (2) | 0.004 (2) | 0.0132 (19) |
N4 | 0.041 (3) | 0.025 (2) | 0.036 (3) | −0.017 (2) | 0.002 (2) | 0.012 (2) |
N5 | 0.049 (3) | 0.033 (2) | 0.028 (3) | −0.014 (2) | 0.000 (2) | 0.011 (2) |
N6 | 0.035 (3) | 0.041 (3) | 0.042 (3) | −0.009 (2) | −0.006 (3) | 0.023 (2) |
C1 | 0.037 (4) | 0.036 (3) | 0.042 (4) | −0.017 (3) | −0.003 (3) | 0.007 (3) |
C2 | 0.049 (4) | 0.041 (3) | 0.049 (4) | −0.003 (3) | −0.001 (4) | −0.016 (3) |
C3 | 0.040 (4) | 0.054 (4) | 0.025 (3) | −0.017 (3) | 0.017 (3) | 0.007 (3) |
C4 | 0.056 (4) | 0.032 (3) | 0.023 (3) | −0.021 (3) | 0.000 (3) | 0.005 (2) |
C5 | 0.024 (3) | 0.033 (3) | 0.025 (3) | −0.007 (2) | 0.011 (3) | 0.004 (2) |
C6 | 0.023 (3) | 0.024 (2) | 0.025 (3) | −0.002 (2) | 0.003 (2) | 0.017 (2) |
C7 | 0.037 (4) | 0.020 (2) | 0.031 (3) | −0.009 (2) | −0.010 (3) | 0.008 (2) |
C8 | 0.042 (4) | 0.023 (3) | 0.017 (3) | −0.006 (3) | −0.008 (3) | 0.008 (2) |
C9 | 0.033 (4) | 0.037 (3) | 0.023 (3) | −0.011 (3) | −0.009 (3) | 0.011 (2) |
C10 | 0.045 (4) | 0.025 (3) | 0.029 (3) | −0.005 (3) | 0.001 (3) | −0.005 (2) |
C11 | 0.025 (4) | 0.059 (4) | 0.048 (4) | −0.007 (3) | −0.006 (3) | −0.004 (3) |
C12 | 0.055 (4) | 0.052 (3) | 0.021 (3) | −0.012 (3) | 0.007 (3) | 0.012 (3) |
C13 | 0.050 (4) | 0.049 (4) | 0.030 (3) | −0.020 (3) | −0.007 (3) | 0.017 (3) |
C14 | 0.040 (4) | 0.025 (3) | 0.037 (4) | −0.001 (3) | 0.006 (3) | 0.001 (3) |
C15 | 0.036 (4) | 0.037 (3) | 0.049 (4) | −0.020 (3) | 0.000 (3) | 0.008 (3) |
C16 | 0.068 (5) | 0.031 (3) | 0.059 (5) | −0.023 (3) | −0.014 (4) | 0.006 (3) |
C17 | 0.059 (5) | 0.024 (3) | 0.056 (4) | −0.026 (3) | −0.003 (4) | 0.008 (3) |
C18 | 0.054 (4) | 0.038 (3) | 0.055 (3) | −0.028 (3) | −0.006 (3) | 0.023 (3) |
O1W | 0.039 (3) | 0.030 (2) | 0.064 (3) | −0.005 (2) | −0.010 (2) | 0.017 (2) |
O2W | 0.049 (3) | 0.044 (2) | 0.038 (3) | −0.025 (2) | 0.002 (2) | 0.007 (2) |
O3W | 0.092 (5) | 0.066 (4) | 0.070 (4) | −0.044 (3) | −0.029 (3) | 0.039 (3) |
O4W | 0.185 (8) | 0.101 (5) | 0.079 (5) | −0.095 (6) | −0.054 (5) | 0.062 (4) |
Zn—O1W | 2.019 (4) | C4—H4 | 0.9300 |
Zn—O1 | 2.068 (4) | C5—C6 | 1.469 (7) |
Zn—N2 | 2.073 (4) | C7—C14 | 1.463 (7) |
Zn—O2W | 2.154 (5) | C8—C9 | 1.510 (7) |
Zn—N3 | 2.193 (4) | C9—C10 | 1.346 (7) |
Zn—N1 | 2.271 (4) | C10—C11 | 1.414 (8) |
S—O2 | 1.474 (4) | C10—H10 | 0.9300 |
S—O4 | 1.479 (4) | C11—C12 | 1.368 (8) |
S—O1 | 1.480 (4) | C11—H11 | 0.9300 |
S—O3 | 1.498 (4) | C12—C13 | 1.377 (8) |
N1—C1 | 1.311 (7) | C12—H12 | 0.9300 |
N1—C5 | 1.372 (6) | C13—H13 | 0.9300 |
N2—C8 | 1.326 (6) | C14—C15 | 1.386 (7) |
N2—C6 | 1.349 (6) | C15—C16 | 1.396 (8) |
N3—C13 | 1.350 (7) | C15—H15 | 0.9300 |
N3—C9 | 1.369 (6) | C16—C17 | 1.364 (8) |
N4—C6 | 1.340 (6) | C16—H16 | 0.9300 |
N4—C7 | 1.343 (6) | C17—C18 | 1.372 (8) |
N5—C8 | 1.334 (6) | C17—H17 | 0.9300 |
N5—C7 | 1.360 (7) | C18—H18 | 0.9300 |
N6—C18 | 1.339 (7) | O1W—H1WA | 0.82 (2) |
N6—C14 | 1.364 (7) | O1W—H1WB | 0.82 (2) |
C1—C2 | 1.422 (8) | O2W—H2WA | 0.82 (3) |
C1—H1 | 0.9300 | O2W—H2WB | 0.82 (3) |
C2—C3 | 1.377 (8) | O3W—H3WA | 0.82 (3) |
C2—H2 | 0.9300 | O3W—H3WB | 0.82 (2) |
C3—C4 | 1.362 (7) | O4W—H4WA | 0.82 (3) |
C3—H3 | 0.9300 | O4W—H4WB | 0.82 (5) |
C4—C5 | 1.373 (7) | ||
O1W—Zn—O1 | 87.93 (17) | N1—C5—C4 | 123.2 (5) |
O1W—Zn—N2 | 174.68 (19) | N1—C5—C6 | 114.2 (4) |
O1—Zn—N2 | 97.22 (16) | C4—C5—C6 | 122.5 (5) |
O1W—Zn—O2W | 88.71 (17) | N4—C6—N2 | 123.2 (5) |
O1—Zn—O2W | 175.89 (15) | N4—C6—C5 | 122.1 (5) |
N2—Zn—O2W | 86.09 (16) | N2—C6—C5 | 114.7 (4) |
O1W—Zn—N3 | 105.84 (16) | N4—C7—N5 | 125.7 (5) |
O1—Zn—N3 | 94.99 (16) | N4—C7—C14 | 117.4 (5) |
N2—Zn—N3 | 75.17 (15) | N5—C7—C14 | 116.8 (5) |
O2W—Zn—N3 | 88.19 (16) | N2—C8—N5 | 124.9 (5) |
O1W—Zn—N1 | 105.48 (16) | N2—C8—C9 | 116.2 (5) |
O1—Zn—N1 | 90.39 (16) | N5—C8—C9 | 118.9 (4) |
N2—Zn—N1 | 73.25 (15) | C10—C9—N3 | 126.7 (5) |
O2W—Zn—N1 | 88.23 (17) | C10—C9—C8 | 121.6 (5) |
N3—Zn—N1 | 148.38 (15) | N3—C9—C8 | 111.7 (4) |
O2—S—O4 | 108.6 (2) | C9—C10—C11 | 116.9 (6) |
O2—S—O1 | 110.5 (2) | C9—C10—H10 | 121.5 |
O4—S—O1 | 108.5 (2) | C11—C10—H10 | 121.5 |
O2—S—O3 | 108.3 (2) | C12—C11—C10 | 117.6 (6) |
O4—S—O3 | 110.2 (3) | C12—C11—H11 | 121.2 |
O1—S—O3 | 110.7 (2) | C10—C11—H11 | 121.2 |
S—O1—Zn | 134.5 (2) | C11—C12—C13 | 121.7 (6) |
C1—N1—C5 | 117.0 (5) | C11—C12—H12 | 119.1 |
C1—N1—Zn | 128.0 (4) | C13—C12—H12 | 119.1 |
C5—N1—Zn | 115.0 (3) | N3—C13—C12 | 121.9 (6) |
C8—N2—C6 | 117.2 (4) | N3—C13—H13 | 119.1 |
C8—N2—Zn | 120.0 (3) | C12—C13—H13 | 119.1 |
C6—N2—Zn | 122.6 (3) | N6—C14—C15 | 121.3 (5) |
C13—N3—C9 | 115.1 (5) | N6—C14—C7 | 118.6 (5) |
C13—N3—Zn | 128.1 (4) | C15—C14—C7 | 120.1 (5) |
C9—N3—Zn | 116.8 (3) | C14—C15—C16 | 120.3 (6) |
C6—N4—C7 | 115.1 (5) | C14—C15—H15 | 119.8 |
C8—N5—C7 | 113.9 (4) | C16—C15—H15 | 119.8 |
C18—N6—C14 | 117.0 (5) | C17—C16—C15 | 117.5 (6) |
N1—C1—C2 | 124.0 (5) | C17—C16—H16 | 121.2 |
N1—C1—H1 | 118.0 | C15—C16—H16 | 121.2 |
C2—C1—H1 | 118.0 | C16—C17—C18 | 119.8 (5) |
C3—C2—C1 | 116.1 (5) | C16—C17—H17 | 120.1 |
C3—C2—H2 | 122.0 | C18—C17—H17 | 120.1 |
C1—C2—H2 | 122.0 | N6—C18—C17 | 123.9 (6) |
C4—C3—C2 | 121.7 (5) | N6—C18—H18 | 118.0 |
C4—C3—H3 | 119.1 | C17—C18—H18 | 118.0 |
C2—C3—H3 | 119.1 | H1WA—O1W—H1WB | 106 (2) |
C3—C4—C5 | 118.0 (5) | H2WB—O2W—H2WA | 105 (2) |
C3—C4—H4 | 121.0 | H3WA—O3W—H3WB | 104 (3) |
C5—C4—H4 | 121.0 | H4WB—O4W—H4WA | 104 (5) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1W—H1WA···O4W | 0.82 (2) | 2.01 (2) | 2.741 (8) | 148 (3) |
O1W—H1WB···O4i | 0.82 (2) | 2.04 (2) | 2.684 (6) | 135 (3) |
O2W—H2WA···O2i | 0.82 (3) | 1.93 (2) | 2.705 (6) | 156 (1) |
O2W—H2WB···N6ii | 0.82 (3) | 2.05 (2) | 2.849 (6) | 165 (4) |
O3W—H3WA···O3 | 0.82 (3) | 2.23 (2) | 2.898 (8) | 139 (3) |
O3W—H3WB···O4iii | 0.82 (2) | 2.21 (3) | 2.868 (7) | 137 (4) |
O4W—H4WA···O3iv | 0.82 (3) | 2.09 (6) | 2.778 (7) | 141 (8) |
O4W—H4WB···O3Wi | 0.82 (5) | 2.45 (6) | 3.263 (14) | 171 (12) |
C11—H11···O2v | 0.93 | 2.38 | 3.250 (7) | 156 |
C13—H13···O3Wi | 0.93 | 2.41 | 3.228 (8) | 147 |
Symmetry codes: (i) x−1, y, z; (ii) −x+1, −y+1, −z; (iii) −x+2, −y, −z+1; (iv) −x+1, −y, −z+1; (v) −x+1, −y+1, −z+1. |
Experimental details
Crystal data | |
Chemical formula | [Zn(SO4)(C18H12N6)(H2O)2]·2H2O |
Mr | 545.83 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 293 |
a, b, c (Å) | 7.7120 (15), 11.771 (2), 12.523 (3) |
α, β, γ (°) | 85.27 (3), 75.38 (3), 75.82 (3) |
V (Å3) | 1066.2 (4) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 1.31 |
Crystal size (mm) | 0.32 × 0.12 × 0.12 |
Data collection | |
Diffractometer | Rigaku AFC-6S diffractometer |
Absorption correction | ψ scan (North et al., 1968) |
Tmin, Tmax | 0.78, 0.85 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 5725, 4670, 2117 |
Rint | 0.076 |
(sin θ/λ)max (Å−1) | 0.642 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.058, 0.140, 0.92 |
No. of reflections | 4670 |
No. of parameters | 336 |
No. of restraints | 18 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.90, −1.00 |
Computer programs: MSC/AFC Diffractometer Control Software (Molecular Structure Corporation, 1988), MSC/AFC Diffractometer Control Software, SHELXTL/PC (Sheldrick, 1994), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), XP in SHELXTL/PC, SHELXL97.
Zn—O1W | 2.019 (4) | Zn—N1 | 2.271 (4) |
Zn—O1 | 2.068 (4) | S—O2 | 1.474 (4) |
Zn—N2 | 2.073 (4) | S—O4 | 1.479 (4) |
Zn—O2W | 2.154 (5) | S—O1 | 1.480 (4) |
Zn—N3 | 2.193 (4) | S—O3 | 1.498 (4) |
O1W—Zn—O1 | 87.93 (17) | N2—Zn—N3 | 75.17 (15) |
O1W—Zn—N2 | 174.68 (19) | O2W—Zn—N3 | 88.19 (16) |
O1—Zn—N2 | 97.22 (16) | O1W—Zn—N1 | 105.48 (16) |
O1W—Zn—O2W | 88.71 (17) | O1—Zn—N1 | 90.39 (16) |
O1—Zn—O2W | 175.89 (15) | N2—Zn—N1 | 73.25 (15) |
N2—Zn—O2W | 86.09 (16) | O2W—Zn—N1 | 88.23 (17) |
O1W—Zn—N3 | 105.84 (16) | N3—Zn—N1 | 148.38 (15) |
O1—Zn—N3 | 94.99 (16) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1W—H1WA···O4W | 0.82 (2) | 2.01 (2) | 2.741 (8) | 148 (3) |
O1W—H1WB···O4i | 0.82 (2) | 2.04 (2) | 2.684 (6) | 135 (3) |
O2W—H2WA···O2i | 0.82 (3) | 1.93 (2) | 2.705 (6) | 156.1 (14) |
O2W—H2WB···N6ii | 0.82 (3) | 2.05 (2) | 2.849 (6) | 165 (4) |
O3W—H3WA···O3 | 0.82 (3) | 2.23 (2) | 2.898 (8) | 139 (3) |
O3W—H3WB···O4iii | 0.82 (2) | 2.21 (3) | 2.868 (7) | 137 (4) |
O4W—H4WA···O3iv | 0.82 (3) | 2.09 (6) | 2.778 (7) | 141 (8) |
O4W—H4WB···O3Wi | 0.82 (5) | 2.45 (6) | 3.263 (14) | 171 (12) |
C11—H11···O2v | 0.93 | 2.38 | 3.250 (7) | 156 |
C13—H13···O3Wi | 0.93 | 2.41 | 3.228 (8) | 147 |
Symmetry codes: (i) x−1, y, z; (ii) −x+1, −y+1, −z; (iii) −x+2, −y, −z+1; (iv) −x+1, −y, −z+1; (v) −x+1, −y+1, −z+1. |
Sulfate-metal complexes have been extensively studied over the years, and their appeal still appears to be maintained: one third of all structural research on the subject has been performed in the last three years [Cambridge Structural Database (CSD), April 2004 Release; Allen, 2002]. There are good reasons for this appeal: in addition to the important role played by the anion in metal-organic chemistry, in recent times some biology-related ones have been reported, viz. its participation in the biosynthesis of cysteine and other S-containing molecules in biological systems. Another focus of our interest in the present work on Zn-sulfate complexes arises as a result of findings from X-ray analyses that the cation may be present in enzyme systems where the sulfate anion is a substrate (Tamasi & Cini, 2003). Finally, to give examples of some applied investigations in which the anion is involved, it can be mentioned that metal sulfate compounds have been studied in relation to porous-framework materials (Khan et al., 2001), and in the chemistry relating to cisplatin (Reedijk, 1992).
To this broad span of interests it can added, as a bonus, that sulfate complexes having polycyclic aromatic ligands (and, additionally, aqua molecules) in their coordination polyhedra have been shown to be extremely prolific in generating crystal structures with a variety of non-covalent interactions. These may be through conventional hydrogen bonds and/or through medium-range contacts linking aromatic rings, either in a parallel displaced arrangement (hereinafter π–π) or in an edge-to-face (or point-to-face) T-shaped conformation (C—H···π) (Janiak, 2000).
It can be concluded, then, that sulfate complexes very often produce interesting crystal structures. Confirming this assertion, we report here a crystallographic study of the title compound, (I), which is a zinc(II) complex with the tridentate ligand 2,4,6-tris(2-pyridyl)-1,3,5-triazine (tpt). \sch
In (I), the metal complex is monomeric, and a distorted octahedral Zn centre is coordinated by three N donors from the tridentate tpt ligand, two cis-related aqua ligands and an O atom of a monodentate sulfate group (Fig. 1).
Several factors might affect the regular geometry of the coordination polyhedron, e.g. the Jahn-Teller effect typical of a d10 metal atom, but the main distortion of (I) is certainly due to the steric limitations imposed by the tpt ligand. The bond lengths to the central metal atom are clearly differentiated into two groups, with three shorter ones to an aqua O atom (O1W), a sulfate O atom (O1) and the central tpt N atom (N2), and three longer ones to the second aqua O atom (O2W) and the two outermost N atoms in the organic ligand (N1 and N3). The asymmetry in the Zn—N bond lengths may be attributed to the short covalent radius of ZnII and to the rather inflexible character of the tpt skeleton, which forces a closer approach of the central N atom. A search of the CSD revealed that 16 compounds in which Zn is complexed to tpt (or some closely related ligand) display a similar effect, with a mean Zn—Ncentral distance of 2.077 (12) Å, and Zn—Nlateral distances of 2.173 (12) (shorter) and 2.199 (17) Å (longer). These compare with 2.073 (4), 2.193 (4) and 2.271 (4) Å, respectively, in (I). Considering these values, it is evident that the marked asymmetry (ca 6%) of the two lateral bonds for (I) is much larger than the average. This is a rather unusual way of binding for these tridentate ligands. Also, the two aqua ligands present very different coordination lengths (Δ Zn—Owater ca 4%), with that which is trans to the short Zn—N2 bond being shorter. Thus, the N2—Zn—O1W axis is significantly shorter, giving the polyhedron a marked oblate character.
The monodentate sulfate ligand binds through atom O1, with a bond distance on the shorter side of the whole range, but there is no correlation with the corresponding S—O bond distances, the double-bond character being rather delocalized. A peculiar feature of the structure of (I) is the leaning of the sulfate anion towards the tpt group, driving one of its free O atoms to be at an almost colliding distance from one of the coordinated N atoms [O2···N2 2.92 (1) Å]. As a consequence of this repulsion, the N2—Zn—O1 bond angle is larger than any of the remaining three (cis) angles involving atom O1. This binding behaviour is quite unusual: we could not trace in the literature any mono-coordinated sulfate complex (irrespective of cation) in which any of its three free O atoms is less than 3.00 Å from a coordinated N or O atom, unless mediated by hydrogen bonding.
The tpt ligand in (I) presents a planar core determined by the three coordinated heterocycles (mean deviation from the least squares plane 0.06 Å), while the remaining terminal pyridyl group is rotated (out of this plane) by 6.9 (1)°.
The profuse availability of donors and acceptors for hydrogen bonding, as well as of aromatic groups with potential to enter into π–π interactions, gives rise to a very complex system of second-order interactions, defining the packing characteristics of the structure. Monomers connected to each other form double chains (or strips) embracing the symmetry centres at (0,1/2,0) and (1/2,1/2,0), while running along the a axis (Fig. 2). The internal single-chain linkage is achieved through two strong hydrogen bonds which involve the two aqua ligands as donors and atoms O2 and O4 from the sulfate anion as acceptors (Table 2).
The `dimerization' of chains into strips is achieved through the hydrogen bond involving atom O2W as a donor and atom N6 from a neighbouring chain as an acceptor. This chain-to-chain linkage is reinforced by the π–π parallel displacive interaction (Fig. 3) resulting from tpt groups related by the (1/2,1/2,0) symmetry centre and characterized by an interplanar spacing of 3.28 (1) Å, with a distance between centres of 3.60 (1) Å and a slippage angle (Janiak, 2000) of 24.4°. The broad `strips' thus generated, which are the real structural units in (I), connect with each other through hydrogen bonds involving the remaining water molecules O3W and O4W. Through these bonds evolving around the line containing the symmetry centres at (0,0,1/2) and (1/2,0,1/2), the solvate water molecules are attached laterally to the outermost sulfate O atom (O3), serving as strip connectors to define some sort of two-dimensional structures parallel to the (011) plane. Weaker C—H···O interactions, mainly those involving aromatic H atoms, connect these structures with each other into the final three-dimensional assembly.