Isolation and characterization of thiolato complexes of [CpCr(SBz)]2S, isomeric trans [CpMo(CO)(SBz)]2 and [CpMo(SBz)2]2 (Cp = (η5-C5H5), Bz = PhCH2) from the reactivity of bibenzyl disulfide towards [CpM(CO)3]2 (M = Cr, Mo)

The reactions of [CpM(CO)3]2 (M=Cr (1), Mo (3)) with Bz2S2 have been investigated. 1 underwent a facile reaction at ambient temperature which led to the isolation of [CpCr(CO)2]S (5), [CpCr(CO)2(SBz)]2 (6) and [CpCr(SBz)]2S (7) in 28.8, 42.6 and 11.8% yield, respectively. A similar reaction at 110°C with its congener, [CpCr(CO)2]2 (CrCr) (2) yielded only thermolytic products of 5 (40.3%) and Cp4Cr4S4 (8) (10.6%). With the Mo analogue 3, only the decarbonylated [CpMo(CO)2]2 (MoMo) (4) reacts at 70°C to give an isomeric pair of trans syn and anti [CpMo(CO)(SBz)]2 (9a & 9b), [CpMo(SBz)(S)]2 (10) and [CpMo(CO)(SBz)]2S (11) in 43.3, 34.1, 5.5 and 3.1% yield, respectively. A totally decarbonylated new complex of [CpMo(SBz)2]2 (12) was obtained in 33.2% yield from the co-thermolysis of Bz2S2 with 9a at 110°C. All products were fully characterized with NMR and IR spectroscopy and C, H analysis. The molecular structures of 7, 9b and 12 have been elucidated by single crystal X-ray diffraction. Plausible mechanistic pathways leading to the formation of 7, 9 and 12 were discussed.