Synthesis and Characterization of a 1,3-Phenylene-Bridged N-Alkyl Bis(benzimidazole) CCC-NHC Pincer Ligand Precursor: Homobimetallic Silver and Rhodium Complexes and the Catalytic Hydrosilylation of Phenylacetylene

A new CCC-NHC pincer ligand precursor architecture based on 1,3-bis(N-alkylbenzimidazole)benzene has been synthesized and metalated using Ag2O, forming a homobimetallic Ag complex with a metal to ligand ratio of 1:1. The Ag complex was treated with either [Rh(COD)Cl](2) or Rh(COD)(2)OTf and NBu4I to yield a homobimetallic Rh complex by transmetalation. The Rh complexes were characterized, and an X-ray structure is reported. Their catalytic activity in the hydrosilylation of phenylacetylene is reported.