Through the reaction of Ph2AsCl with Et3NH[(m-CO)(m-RS)Fe2(CO)6] formed from Fe3(CO)12, RSH, and Et3N, (m-Ph2As)(m-RS)Fe2(CO)6 (R = Et, Pr, CHMe2, Bu, CMe3) were prepared and characterized by elemental anal., IR and 1H NMR spectroscopy. The crystal structure of the complex with R = CHMe2 was determine by x-ray diffraction. Crystals of the complex are triclinic, space group P1, a 8.623(2), b 12.082(1), c 12.357(2) ? a 84.24(1), b 71.05(1), g 79.48(2)? Z = 2, R = 0.032, Rw = 0.042. This mol. contains a butterfly-shaped cluster skeleton Fe2SAs, to its S atom CHMe2 group is connected by an e-type of bond. The Fe-Fe bond length is 2.626 ? which is quite close to those in (m-EtS)2Fe2(CO)6(m-Me2P)2Fe2(CO)6, and (m-PhS)(m-Ph2P)Fe2(CO)6 (2.537, 2.665, and 2.610 ? resp.).

Key words: INFRARED SPECTROPHOTOMETRY, MOLECULAR STRUCTURE, BENZENE P, IRON COMPLEX, CARBONYL COMPLEX, PROTON MAGNETIC RESONANCE SPECTROMETRY, BRIDGE COMPOUNDS, SULFUR COMPOUNDS, ARSENIC COMPOUNDS