Synthesis and characterization of homo- and hetero-nuclear mixed thiolate phosphine complexes with Ni II , Pd II , and Pt II . Crystal and molecular structure of bis[µ-(3-dimethylamino-1-propanethiolato)]-bis{[1,2-bis(diphenylphosphino)-ethane]nickel( II )} tetraphenylborate

The following families of complexes have been prepared and characterized: [M{S(CH2)3NHMe2}2-(dppe)][BPh4]2, dppe = Ph2PCH2CH2PPh2, M = Ni, Pd, or Pt; [M{S(CH2)3NMe2}2(dppe)], M = Pd or Pt; [(dppe)M{µ-S(CH2)3NMe2}2M′(dppe)][BPh4]2(M = M′= Ni, Pd, or Pt; M = Ni, M′= Pd; M = Ni, M′= Pt; M = Pd, M′= Pt); and [Ni{Pt[µ-S(CH2)3NMe2]2(dppe)}2][BPh4]2. Infrared spectra indicate that within each family the complexes have the same structure. Crystals of the homonuclear nickel dimer are triclinic, space group P, with a= 14.346(1), b= 14.037(1), c= 13.207(1)Å, α= 105.79(1), β= 90.81(1), and γ= 113.06(1)°. The crystal structure consists of centrosymmetric binuclear thiolate-bridged cations and anions, well separated. The corresponding homonuclear complexes of PdII and PtII are isomorphous. The co-ordination of the metal atoms in the trinuclear complex [(dppe)Pt(µ-SR)2Ni(µ-SR)2Pt(dppe)]2+[R =(CH2)3NMe2], has been deduced from 31P-{1H} n.m.r. data. In solution the platinum mononuclear complexes and the nickel dimeric species are the most stable.