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A single MoFe_3S_4 cubane-like cluster compound has been synthesized through spon-taneous self-assembly of simple inorganic salts with organosulfur ligand for the first time. (Et_4N)-[MoFe_3S_4(Et_2NCSS)_5]CH_3CN(1) is quite stable in air. The crystal of 1 is monoclinic with spacegroup P2_1/c, a=22.897(3),b=12.399(2),c=20.928(4),β=97.15(1)°, and Z=4. A fullmatrix least-squares refinement with 6725 unique reflections for all nonhydrogen atoms givesR=0.068. The anion of 1 is the first isolated single MoFe_3S_4 cubane cluster with core oxidation state [Mo-Fe_3S_4]~(4+). The distance between the two 6-coordinate metal atoms (Mo,Fe) is 2.624 , which isthe shortest M-M’bond observed for Mo-Fe-S clusters so far and the only one shorter than sim-ilar distances in FeMo-cofactor. The bond orders of this anion were calculated by EHMO method and the results coincide withthe general rule. The structural feature and the unusual stability of 1 can be attributed to the bidentatechelating effect of Et_2NCSS-, which leads to high coordination of metal atoms and the various ligatedtypes.
A single MoFe_3S_4 cubane-like cluster compound has been synthesized through spon-taneous self-assembly of simple inorganic salts with organosulfur ligand for the first time. (Et_4N) - [MoFe_3S_4 (Et_2NCSS) _5] CH_3CN (1) is quite stable in air . The crystal of 1 is monoclinic with spacegroup P2_1 / c, a = 22.897 (3), b = 12.399 (2), c = 20.928 (4), β = 97.15 (1) °, and Z = -squares refinement with 6725 unique reflections for all nonhydrogen atoms gives R = 0.068. The anion of 1 is the first isolated single MoFe_3S_4 cubane cluster with core oxidation state [Mo-Fe_3S_4] ~ (4+). The distance between the two 6-coordinate metal atoms (Mo, Fe) is 2.624, which is the shortest M-M’bond observed for Mo-Fe-S clusters so far and the only one shorter than sim-ilar distances in FeMo-cofactor. The bond orders of this anion were calculated by EHMO method and the results coincide with the general rule. The structural feature and the unusual stability of 1 can be attributed to the bidentatechelating effect of E t_2NCSS-, which leads to high coordination of metal atoms and the various ligatedtypes.