Alkylation and metalation of binuclear anions containing a novel tricyclohexylphosphonioethanetrithiolate ligand S(SR)CC(PCy3)S

The reaction of homobinuclear rhenium–rhenium complex [Re2(CO)6(μ-S2CPCy3)] (1c) with Li[BHEt3] in THF produces anionic 2c which reacts with CS2 affording a new anion 3c, through desulfurization and CS insertion, in a fashion paralel to that of the perviously known Mn–Mn and Mn–Re analogues. Anions 3a–3c undergo allylation and metallation to give neutral products 4a–4k. The structures of [MnRe(CO)6(μ-H){μ-S(SSnBun3)CC(PCy3)S}] (4d) and [MnRe(CO)6(μ-H){μ-S(SC3H5)CC(PCy3)S}] (4h) have been determined by X-ray diffraction revealing the (OC)3Mn–Re(CO)3 core unit bridged by hydride and the novel S-tributylstannyl-, or (S-allyl)-(tricyclohexylphosphonio)ethenetrithiolate ligands.