Coordination chemistry of perhalogenated cyclopentadienes and alkynes—XX. Synthesis of bi- and trimetallic cymantrene derivatives with silver or gold containing ring substituents. First observation of oxidative addition of a halogen-cyclopentadienyl bond to a Ni 0 fragment

Abstract

Treatment of the perhalogenated cymantrenes [C 5X 4Br]Mn(CO) 3 (X = Cl, Br) with butyl lithium and Au(PPh 3)Cl yields, depending on the reaction conditions, the bi- or trimetallic σ, π-bridged cyclopentadienyl complexes [C 5X 5− n (AuPPh 3) n ]Mn(Co) 3 with n = 1 or 2. Similarly, the bimetallic complexes [C 5Cl 4(AgPPh 3)]Mn(CO) 3 and [C 5Cl 4(AuCN′Bu)]Mn(CO) 3 can be obtained. Addition of Ni[PBu 3] 2(C 2H 4) to [C 5Cl 4(AuPBu 3)]Mn(CO) 3 generated in situ results in oxidative addition of one ring CCl bond to Ni 0 to give [C 5Cl 3(AuPBu 3)[Ni(PBu 3) 2Cl]]Mn(CO) 3, the first complex with three different metals attached to one cyclopentadienyl ring. When the lithium cymantrenyl thiolates [C 5Cl 3X(SLi)]Mn(CO) 3 (X = Cl, Li or SLi) are treated with Au(PPh 3)Cl, the gold thiolates [C 5Cl 3Y(SAuPPh 3)]Mn(CO) 3 with Y = Cl, AuPPh 3 or SAuPPh 3 are formed.