
Acta Cryst. (2008). E64, m605-m606 [ doi:10.1107/S1600536808007757 ]
-L-cysteinato(2-)-
4S:S,N,O-[di-
-sulfido-bis[oxidomolybdate(V)](Mo-Mo)]-
-L-cysteinato(2-)-
4S,N,O:S]The title compound, [Mo2Zn(C3H5NO2S)2O2S2(H2O)2], forms a one-dimensional chain. The cysteine S atom of the dinuclear molybdenum complex anion coordinates to the zinc ion, which has a tetrahedral environment by the additional coordination of two water molecules. The one-dimensional chains are connected to each other by hydrogen bonds. The Zn-S(cysteine) distances [2.3599 (6) and 2.3072 (6) Å] are close to the value in ZnS (2.35 Å). The distances and angles within the complex are very close to those reported for the sodium and potassium di-
-sulfide species.
The title compound was prepared by the addition of ZnCl2 to a diluted aqueous solution of Na2[Mo2O2S2(cys)2].4H2O. A crystal suitable for single-crystal X-ray diffraction was selected directly from the prepared sample.
H atoms bonded to C, N, and O (H2O) atoms were located in a difference map and refined with distance restraints of C—H = 0.99 (1), N—H = 0.92 (1), and O—H, 0.84 (1) Å, and with Uiso(H) = 1.2Ueq(C, N, O). The absolute structure was confirmed by the value of Flack parameter (0.003 (7)).
Data collection: CrystalClear (Rigaku, 1999); cell refinement: CrystalClear (Rigaku, 1999); data reduction: CrystalStructure (Rigaku, 2007); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: CrystalStructure (Rigaku, 2007); software used to prepare material for publication: CrystalStructure (Rigaku, 2007).
| [Mo2Zn(C3H5NO2S)2O2S2(H2O)2] | F000 = 612.00 |
| Mr = 627.69 | Dx = 2.472 Mg m−3 |
| Monoclinic, P21 | Mo Kα radiation λ = 0.71070 Å |
| Hall symbol: P 2yb | Cell parameters from 3004 reflections |
| a = 8.6881 (11) Å | θ = 5.5–30.0º |
| b = 10.3529 (8) Å | µ = 3.41 mm−1 |
| c = 9.8686 (11) Å | T = 93.1 K |
| β = 108.2022 (14)º | Platelet, orange |
| V = 843.23 (16) Å3 | 0.35 × 0.30 × 0.10 mm |
| Z = 2 |
| Rigaku Mercury diffractometer | 4549 reflections with F2 > 2σ(F2) |
| Detector resolution: 14.63 pixels mm-1 | Rint = 0.019 |
| ω scans | θmax = 30.0º |
| Absorption correction: multi-scan (Jacobson, 1998) | h = −12→11 |
| Tmin = 0.382, Tmax = 0.727 | k = −14→14 |
| 9357 measured reflections | l = −13→13 |
| 4556 independent reflections |
| Refinement on F2 | w = 1/[σ2(Fo2) + (0.0303P)2 + 0.5406P] where P = (Fo2 + 2Fc2)/3 |
| R[F2 > 2σ(F2)] = 0.019 | (Δ/σ)max = 0.001 |
| wR(F2) = 0.049 | Δρmax = 0.47 e Å−3 |
| S = 1.02 | Δρmin = −0.94 e Å−3 |
| 4556 reflections | Extinction correction: none |
| 209 parameters | Absolute structure: Flack (1983), with 2010 Friedel pairs |
| 15 restraints | Flack parameter: 0.002 (7) |
| H atoms treated by a mixture of independent and constrained refinement |
| [Mo2Zn(C3H5NO2S)2O2S2(H2O)2] | V = 843.23 (16) Å3 |
| Mr = 627.69 | Z = 2 |
| Monoclinic, P21 | Mo Kα |
| a = 8.6881 (11) Å | µ = 3.41 mm−1 |
| b = 10.3529 (8) Å | T = 93.1 K |
| c = 9.8686 (11) Å | 0.35 × 0.30 × 0.10 mm |
| β = 108.2022 (14)º |
| Rigaku Mercury diffractometer | 4556 independent reflections |
| Absorption correction: multi-scan (Jacobson, 1998) | 4549 reflections with F2 > 2σ(F2) |
| Tmin = 0.382, Tmax = 0.727 | Rint = 0.019 |
| 9357 measured reflections |
| R[F2 > 2σ(F2)] = 0.019 | H atoms treated by a mixture of independent and constrained refinement |
| wR(F2) = 0.049 | Δρmax = 0.47 e Å−3 |
| S = 1.02 | Δρmin = −0.94 e Å−3 |
| 4556 reflections | Absolute structure: Flack (1983), with 2010 Friedel pairs |
| 209 parameters | Flack parameter: 0.002 (7) |
| 15 restraints |
Geometry. ENTER SPECIAL DETAILS OF THE MOLECULAR GEOMETRY |
Refinement. Refinement was performed using all reflections. The weighted R-factor (wR) and goodness of fit (S) are based on F2. R-factor (gt) are based on F. The threshold expression of F2 > 2.0 σ>F2) is used only for calculating R-factor (gt). |
| x | y | z | Uiso*/Ueq | ||
| Mo1 | −0.056910 (19) | 0.591229 (16) | 0.808774 (16) | 0.00615 (4) | |
| Mo2 | 0.113206 (19) | 0.533750 (19) | 0.613333 (16) | 0.00647 (4) | |
| Zn1 | −0.46728 (3) | 0.59442 (3) | 0.84366 (3) | 0.01008 (4) | |
| S1 | −0.07812 (7) | 0.40574 (6) | 0.67221 (6) | 0.00917 (8) | |
| S2 | 0.16158 (6) | 0.70395 (5) | 0.77534 (6) | 0.00880 (8) | |
| S3 | −0.22984 (6) | 0.46976 (5) | 0.93439 (5) | 0.00813 (8) | |
| S4 | 0.39318 (6) | 0.59322 (6) | 0.60271 (5) | 0.01009 (8) | |
| O1 | −0.2167 (2) | 0.68209 (17) | 0.71583 (17) | 0.0104 (2) | |
| O2 | 0.00101 (19) | 0.60344 (18) | 0.45909 (16) | 0.0111 (2) | |
| O3 | 0.2203 (2) | 0.45050 (18) | 1.21945 (17) | 0.0125 (3) | |
| O4 | 0.13324 (19) | 0.49461 (16) | 0.98677 (16) | 0.0089 (2) | |
| O5 | 0.4690 (2) | 0.2383 (2) | 0.7999 (2) | 0.0217 (3) | |
| O6 | 0.2865 (2) | 0.39663 (18) | 0.77426 (17) | 0.0125 (3) | |
| O7 | −0.3954 (2) | 0.77830 (18) | 0.9006 (2) | 0.0182 (3) | |
| O8 | −0.54704 (19) | 0.55572 (18) | 1.00931 (17) | 0.0136 (3) | |
| N1 | −0.0163 (2) | 0.70357 (19) | 1.01408 (19) | 0.0087 (3) | |
| N2 | 0.1744 (2) | 0.3658 (2) | 0.4962 (2) | 0.0102 (3) | |
| C1 | 0.0084 (2) | 0.6095 (2) | 1.1320 (2) | 0.0092 (3) | |
| C2 | 0.1322 (2) | 0.5110 (2) | 1.1161 (2) | 0.0083 (3) | |
| C3 | −0.1525 (2) | 0.5421 (2) | 1.1147 (2) | 0.0099 (3) | |
| C4 | 0.3455 (2) | 0.3284 (2) | 0.5675 (2) | 0.0112 (3) | |
| C5 | 0.3694 (2) | 0.3165 (2) | 0.7269 (2) | 0.0116 (4) | |
| C6 | 0.4534 (2) | 0.4378 (2) | 0.5447 (2) | 0.0130 (4) | |
| H1 | 0.0683 | 0.7596 | 1.0256 | 0.010* | |
| H2 | −0.1027 | 0.7551 | 1.0124 | 0.010* | |
| H3 | 0.1090 | 0.2957 | 0.4919 | 0.012* | |
| H4 | 0.1624 | 0.3890 | 0.4039 | 0.012* | |
| H5 | −0.2299 | 0.6042 | 1.1334 | 0.012* | |
| H6 | −0.1366 | 0.4727 | 1.1869 | 0.012* | |
| H7 | 0.0460 | 0.6482 | 1.2291 | 0.011* | |
| H8 | 0.4318 | 0.4416 | 0.4403 | 0.016* | |
| H9 | 0.5706 | 0.4243 | 0.5928 | 0.016* | |
| H10 | 0.3821 | 0.2458 | 0.5359 | 0.013* | |
| H11 | −0.3638 | 0.8290 | 0.8487 | 0.022* | |
| H12 | −0.4303 | 0.8035 | 0.9659 | 0.022* | |
| H13 | −0.5293 | 0.6197 | 1.0646 | 0.016* | |
| H14 | −0.6424 | 0.5281 | 0.9816 | 0.016* |
| U11 | U22 | U33 | U12 | U13 | U23 | |
| Mo1 | 0.00760 (7) | 0.00633 (8) | 0.00567 (7) | 0.00053 (6) | 0.00374 (5) | 0.00047 (6) |
| Mo2 | 0.00756 (7) | 0.00729 (8) | 0.00565 (7) | 0.00067 (6) | 0.00364 (5) | 0.00022 (6) |
| Zn1 | 0.01030 (10) | 0.01118 (12) | 0.00928 (10) | 0.00082 (10) | 0.00382 (8) | −0.00105 (9) |
| S1 | 0.0114 (2) | 0.0085 (2) | 0.0091 (2) | −0.00148 (18) | 0.00549 (17) | −0.00119 (17) |
| S2 | 0.0109 (2) | 0.0077 (2) | 0.0098 (2) | −0.00074 (18) | 0.00601 (17) | −0.00107 (17) |
| S3 | 0.0087 (2) | 0.0085 (2) | 0.0086 (2) | −0.00003 (18) | 0.00480 (16) | −0.00014 (17) |
| S4 | 0.0088 (2) | 0.0127 (2) | 0.0098 (2) | −0.0003 (2) | 0.00436 (16) | 0.00152 (19) |
| O1 | 0.0111 (6) | 0.0117 (8) | 0.0102 (6) | 0.0024 (5) | 0.0060 (5) | 0.0015 (5) |
| O2 | 0.0113 (6) | 0.0135 (8) | 0.0097 (6) | 0.0019 (6) | 0.0048 (5) | 0.0014 (6) |
| O3 | 0.0152 (7) | 0.0123 (8) | 0.0101 (6) | 0.0030 (6) | 0.0039 (5) | 0.0014 (6) |
| O4 | 0.0102 (6) | 0.0099 (7) | 0.0074 (6) | 0.0011 (5) | 0.0041 (5) | 0.0002 (5) |
| O5 | 0.0216 (8) | 0.0185 (9) | 0.0221 (8) | 0.0064 (7) | 0.0027 (7) | 0.0083 (7) |
| O6 | 0.0166 (7) | 0.0129 (8) | 0.0087 (6) | 0.0010 (6) | 0.0049 (5) | −0.0004 (5) |
| O7 | 0.0217 (9) | 0.0131 (8) | 0.0250 (8) | −0.0031 (7) | 0.0146 (7) | −0.0054 (7) |
| O8 | 0.0096 (6) | 0.0217 (10) | 0.0103 (6) | −0.0025 (5) | 0.0045 (5) | −0.0045 (6) |
| N1 | 0.0111 (7) | 0.0069 (8) | 0.0096 (7) | 0.0002 (6) | 0.0053 (6) | 0.0004 (6) |
| N2 | 0.0096 (7) | 0.0125 (9) | 0.0084 (7) | 0.0010 (6) | 0.0026 (6) | −0.0032 (6) |
| C1 | 0.0131 (8) | 0.0086 (10) | 0.0067 (7) | 0.0002 (7) | 0.0043 (6) | −0.0005 (7) |
| C2 | 0.0099 (8) | 0.0060 (10) | 0.0107 (8) | −0.0019 (6) | 0.0058 (6) | −0.0008 (6) |
| C3 | 0.0118 (8) | 0.0109 (9) | 0.0088 (7) | −0.0005 (7) | 0.0060 (6) | 0.0001 (7) |
| C4 | 0.0114 (8) | 0.0130 (10) | 0.0088 (8) | 0.0038 (7) | 0.0024 (6) | −0.0032 (7) |
| C5 | 0.0126 (9) | 0.0095 (10) | 0.0124 (9) | −0.0007 (7) | 0.0034 (7) | 0.0003 (7) |
| C6 | 0.0117 (9) | 0.0186 (11) | 0.0099 (8) | 0.0019 (7) | 0.0052 (7) | −0.0024 (8) |
| Mo1—O1 | 1.6905 (17) | O5—C5 | 1.238 (3) |
| Mo1—O4 | 2.2366 (16) | O6—C5 | 1.279 (3) |
| Mo1—N1 | 2.2662 (19) | O7—H11 | 0.837 |
| Mo1—S1 | 2.3201 (6) | O7—H12 | 0.835 |
| Mo1—S2 | 2.3378 (6) | O8—H13 | 0.841 |
| Mo1—S3 | 2.5572 (6) | O8—H14 | 0.838 |
| Mo1—Mo2 | 2.8354 (3) | N1—C1 | 1.481 (3) |
| Mo2—O2 | 1.6914 (16) | N1—H1 | 0.915 |
| Mo2—N2 | 2.2419 (19) | N1—H2 | 0.917 |
| Mo2—O6 | 2.3044 (18) | N2—C4 | 1.484 (3) |
| Mo2—S2 | 2.3276 (6) | N2—H3 | 0.914 |
| Mo2—S1 | 2.3368 (6) | N2—H4 | 0.915 |
| Mo2—S4 | 2.5428 (6) | C1—C3 | 1.523 (3) |
| Zn1—O8 | 2.0052 (17) | C1—C2 | 1.526 (3) |
| Zn1—O7 | 2.0275 (19) | C1—H7 | 0.995 |
| Zn1—S4i | 2.3072 (6) | C3—H5 | 0.989 |
| Zn1—S3 | 2.3599 (6) | C3—H6 | 0.991 |
| S3—C3 | 1.852 (2) | C4—C5 | 1.527 (3) |
| S4—C6 | 1.838 (3) | C4—C6 | 1.531 (4) |
| S4—Zn1ii | 2.3072 (6) | C4—H10 | 0.996 |
| O3—C2 | 1.237 (3) | C6—H8 | 0.989 |
| O4—C2 | 1.290 (2) | C6—H9 | 0.989 |
| O1—Mo1—O4 | 162.73 (7) | C6—S4—Zn1ii | 102.50 (7) |
| O1—Mo1—N1 | 94.11 (7) | C6—S4—Mo2 | 99.79 (8) |
| O4—Mo1—N1 | 69.93 (6) | Zn1ii—S4—Mo2 | 99.22 (2) |
| O1—Mo1—S1 | 104.04 (6) | C2—O4—Mo1 | 119.10 (14) |
| O4—Mo1—S1 | 89.50 (4) | C5—O6—Mo2 | 117.99 (14) |
| N1—Mo1—S1 | 154.97 (5) | Zn1—O7—H11 | 123.4 |
| O1—Mo1—S2 | 102.18 (6) | Zn1—O7—H12 | 110.6 |
| O4—Mo1—S2 | 84.32 (4) | H11—O7—H12 | 122.9 |
| N1—Mo1—S2 | 87.91 (5) | Zn1—O8—H13 | 109.3 |
| S1—Mo1—S2 | 104.59 (2) | Zn1—O8—H14 | 111.1 |
| O1—Mo1—S3 | 91.69 (6) | H13—O8—H14 | 116.3 |
| O4—Mo1—S3 | 78.52 (4) | C1—N1—Mo1 | 107.99 (13) |
| N1—Mo1—S3 | 76.70 (5) | C1—N1—H1 | 113.9 |
| S1—Mo1—S3 | 85.55 (2) | Mo1—N1—H1 | 109.3 |
| S2—Mo1—S3 | 160.022 (19) | C1—N1—H2 | 108.3 |
| O1—Mo1—Mo2 | 105.18 (6) | Mo1—N1—H2 | 112.6 |
| O4—Mo1—Mo2 | 91.51 (4) | H1—N1—H2 | 104.8 |
| N1—Mo1—Mo2 | 138.35 (5) | C4—N2—Mo2 | 108.76 (13) |
| S1—Mo1—Mo2 | 52.760 (15) | C4—N2—H3 | 109.3 |
| S2—Mo1—Mo2 | 52.411 (14) | Mo2—N2—H3 | 113.3 |
| S3—Mo1—Mo2 | 137.441 (15) | C4—N2—H4 | 109.0 |
| O2—Mo2—N2 | 91.69 (8) | Mo2—N2—H4 | 109.8 |
| O2—Mo2—O6 | 162.14 (7) | H3—N2—H4 | 106.6 |
| N2—Mo2—O6 | 70.64 (6) | N1—C1—C3 | 108.11 (17) |
| O2—Mo2—S2 | 103.00 (6) | N1—C1—C2 | 107.01 (16) |
| N2—Mo2—S2 | 156.97 (5) | C3—C1—C2 | 109.49 (18) |
| O6—Mo2—S2 | 93.10 (5) | N1—C1—H7 | 114.5 |
| O2—Mo2—S1 | 102.18 (6) | C3—C1—H7 | 107.9 |
| N2—Mo2—S1 | 89.44 (5) | C2—C1—H7 | 109.8 |
| O6—Mo2—S1 | 80.89 (5) | O3—C2—O4 | 123.7 (2) |
| S2—Mo2—S1 | 104.38 (2) | O3—C2—C1 | 121.88 (18) |
| O2—Mo2—S4 | 98.59 (6) | O4—C2—C1 | 114.38 (18) |
| N2—Mo2—S4 | 77.44 (5) | C1—C3—S3 | 109.75 (13) |
| O6—Mo2—S4 | 75.53 (5) | C1—C3—H5 | 109.6 |
| S2—Mo2—S4 | 82.83 (2) | S3—C3—H5 | 112.2 |
| S1—Mo2—S4 | 155.71 (2) | C1—C3—H6 | 109.6 |
| O2—Mo2—Mo1 | 104.26 (5) | S3—C3—H6 | 109.0 |
| N2—Mo2—Mo1 | 140.49 (5) | H5—C3—H6 | 106.7 |
| O6—Mo2—Mo1 | 91.59 (4) | N2—C4—C5 | 107.66 (18) |
| S2—Mo2—Mo1 | 52.737 (15) | N2—C4—C6 | 107.82 (19) |
| S1—Mo2—Mo1 | 52.226 (15) | C5—C4—C6 | 108.60 (18) |
| S4—Mo2—Mo1 | 133.300 (15) | N2—C4—H10 | 116.5 |
| O8—Zn1—O7 | 96.70 (7) | C5—C4—H10 | 107.4 |
| O8—Zn1—S4i | 129.42 (5) | C6—C4—H10 | 108.7 |
| O7—Zn1—S4i | 107.94 (6) | O5—C5—O6 | 125.6 (2) |
| O8—Zn1—S3 | 93.73 (5) | O5—C5—C4 | 119.9 (2) |
| O7—Zn1—S3 | 104.55 (6) | O6—C5—C4 | 114.4 (2) |
| S4i—Zn1—S3 | 120.25 (2) | C4—C6—S4 | 110.80 (15) |
| Mo1—S1—Mo2 | 75.014 (19) | C4—C6—H8 | 104.8 |
| Mo2—S2—Mo1 | 74.853 (18) | S4—C6—H8 | 108.1 |
| C3—S3—Zn1 | 98.94 (7) | C4—C6—H9 | 114.2 |
| C3—S3—Mo1 | 100.08 (7) | S4—C6—H9 | 109.0 |
| Zn1—S3—Mo1 | 97.09 (2) | H8—C6—H9 | 109.7 |
| Symmetry codes: (i) x−1, y, z; (ii) x+1, y, z. |
| D—H···A | D—H | H···A | D···A | D—H···A |
| O7—H11···O3iii | 0.84 | 2.03 | 2.832 (2) | 161 |
| O7—H11···O4iii | 0.84 | 2.75 | 3.139 (2) | 110 |
| O7—H12···O5iii | 0.84 | 2.53 | 3.239 (3) | 144 |
| O7—H12···O6iii | 0.84 | 2.66 | 3.285 (2) | 133 |
| O7—H12···O8iv | 0.84 | 2.64 | 3.093 (2) | 116 |
| O8—H13···O5iii | 0.84 | 1.77 | 2.604 (2) | 171 |
| O8—H14···O4i | 0.84 | 2.00 | 2.789 (2) | 158 |
| O8—H14···O6i | 0.84 | 2.37 | 2.844 (2) | 116 |
| N1—H2···O4iii | 0.92 | 2.49 | 3.179 (2) | 132 |
| N1—H2···O7 | 0.92 | 2.45 | 3.224 (2) | 143 |
| N2—H3···O2v | 0.91 | 2.32 | 3.212 (2) | 164 |
| N2—H4···O1v | 0.92 | 2.56 | 2.934 (2) | 105 |
| N2—H4···O3vi | 0.92 | 2.13 | 3.011 (2) | 161 |
| Symmetry codes: (iii) −x, y+1/2, −z+2; (iv) −x−1, y+1/2, −z+2; (i) x−1, y, z; (v) −x, y−1/2, −z+1; (vi) x, y, z−1. |
| Mo1—S1 | 2.3201 (6) | Mo2—S4 | 2.5428 (6) |
| Mo1—S2 | 2.3378 (6) | Zn1—O8 | 2.0052 (17) |
| Mo1—S3 | 2.5572 (6) | Zn1—O7 | 2.0275 (19) |
| Mo1—Mo2 | 2.8354 (3) | Zn1—S4i | 2.3072 (6) |
| Mo2—S2 | 2.3276 (6) | Zn1—S3 | 2.3599 (6) |
| Mo2—S1 | 2.3368 (6) | ||
| O8—Zn1—O7 | 96.70 (7) | O8—Zn1—S3 | 93.73 (5) |
| O8—Zn1—S4i | 129.42 (5) | O7—Zn1—S3 | 104.55 (6) |
| O7—Zn1—S4i | 107.94 (6) | S4i—Zn1—S3 | 120.25 (2) |
| Symmetry codes: (i) x−1, y, z. |
| D—H···A | D—H | H···A | D···A | D—H···A |
| O7—H11···O3ii | 0.84 | 2.03 | 2.832 (2) | 161 |
| O8—H13···O5ii | 0.84 | 1.77 | 2.604 (2) | 171 |
| O8—H14···O4i | 0.84 | 2.00 | 2.789 (2) | 158 |
| Symmetry codes: (ii) −x, y+1/2, −z+2; (i) x−1, y, z. |
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Molybdenum and L-cysteine are important components of many enzymes. X-ray structures of sulfur/oxygen-bridged dinuclear molybdenum complexes with L-cysteine ligands: Na2[Mo2(µ-S)2O2(cys)2].4H2O (Brown & Jeffreys, 1973; Hong et al., 1983); K2[Mo2S2O2(cys)2].4H2O.CH3OH (Xing et al., 1998), Ca[Mo2(µ-S)(µ-O)O2(cys)2].3H2O (Shibahara et al., 1987), and Na2[Mo2O4(cys)2].5H2O (Knox & Prout, 1969; Kay & Mitchell, 1970; Liu & Williams, 1981), have been reported, where alkaline or alkaline earth metals are counter cations, and the existence of metal-oxygen (cysteine oxygen) bonds has been reported. Seeking another crystal structure type, we used Zn2+ion, as the counter ion. The present structural study of the complex compound Zn[Mo2O2S2(cys)2].2H2O (I) reveals the existence of Zn—S(cysteine sulfur) bonds, which result in polymerization; this type of Zn—S bond has been found in zinc finger proteins. The asymmetric unit of I is shown in Fig. 1 and a view of part of a one-dimensional polymeric chain of I is shown in Fig. 2. The zinc ion bridges the molybdenum complex anions: the coordination of the cysteine sulfur in the complex anion to the zinc ion results in the formation of one dimensional chains, where the zinc forms a tetrahedral structure by the additional coordination of two water molecules. The one dimensional chains are connected to each other by hydrogen bonds. Intra-chain hydrogen bonds also exist. The dimensions of the molybdenum complex and of the zinc tetrahedron are listed in Table 1, and the hydrogen bonds are listed in Table 2. The Zn—S(cysteine) distances (2.3599 (6), 2.3072 (6) Å) are close to that in ZnS (2.35 Å). The distances and angles within the complex are very close to those reported in the sodium and potassium salts in the di-µ-sulfide species.