Heteroleptic Binuclear Palladium(II)Complexes with P_2Pd(S_2)Cores:X-ray Crystal Structures of(PdCl_2)_2(mu-Ph2PC ident to CPPh_2)_2 and[Pd(MET)]_2(mu-Ph_2PC ident to CPPh_2)_2 where MET is(Z)-1,4-Dimethoxy-1,4-dioxobut-2-ene-2,3-dithiolate

摘要

1,2-Bis(diphenylphosphino)acetylene(abbreviated as dppa:Ph2PCCPPh2)is a linear diphosphine ligand,which has been used as a bridging ligand between metals or metal clusters such as Cu-chalcogenide,Ru3-cluster,Ag(I),W2(CO)6,Mo(CO)4,Pt(C6F5)2,Pt(SC6F5)2,Ru(acac)2 and MX2(M=Pd,Pt;X=Cl,Br,I,SCN).In these complexes,two phosphine groups in dppa coordinate to the metals.If the acetylenic group in dppa participates in the coordination of the metals,clusters such as the Cu-chalcogenide cluster and Co-carbonyl cluster can be formed.The dppa ligand shows more versatile modes of coordination chemistry than in the case where only two phosphines participate in the coordination.Previous studies on dppa-complexes mainly focused on their synthesis,X-ray crystal structure analysis and(in some cases)electrochemical properties.Metal-dppa complexes with a monothiolate terminating ligand also belong to this family,but only a few have been reported so far.