Synthesis and Crystal Structures of Diiron Dithiolate Complexes Containing Diphosphine Ligands

摘要

As the active site model of [FeFe]-hydrogenases, complexes [(μ-PDT) Fe_2(CO)_5]_2(dppb) (PDT = SCH_2CH_2CH_2S, dppb = Ph_2PCH_2CH_2CH_2CH_2PPh_2) (1) and [(μ-SCH_2)_2NCH_2CO_2Me]Fe_2(CO)_5(dppm) (dppm = Ph_2PCH_2PPh_2) (2) were prepared by reactions of (μ-PDT)Fe_2(CO)_6 (A) or [(μ-SCH_2)_2NCH_2CO_2Me]Fe_2(CO)_6 (B) with dppb or dppm in the presence of the decarbonylating agent Me_3NO?2H_2O in MeCN at room temperature. Complex 1 was characterized by elemental analysis, IR, and ~1H (~(31)P, ~(13)C) NMR spectroscopic techniques. In addition, the molecular structures of 1 and 2 have been confirmed by single crystalX-ray diffraction analysis. In the crystal structure of 1, two phosphorus atoms of dppb reside in a basal position of the squarepyramidal coordination sphere of the Fe2 and Fe3 atoms. However, in the crystal structure of 2, P1 atom of dppm resides in an apical position of the square-pyramidal coordination sphere of the Fe2 atom.