Rhodium, iridium and gold complexes of the short-bite ligand 1-benzyl-2-imidazolyldiphenylphosphine

Abstract

Reactions of [{M(μ-Cl)(cod)} 2] (M=Rh, Ir) with 1-benzyl-2-imidazolyldiphenylphosphine gave the mononuclear P-bonded compounds [MCl(cod)(Ph 2PBzIm)]. They react with [M(cod)(acetone) x ]BF 4 to give the cationic [{M(cod)} 2(μ-Cl)(μ-Ph 2PBzIm)] + complexes, while they react with silver salts to give the homometallic dinuclear complexes HT-[{M(μ-Ph 2PBzIm)(cod)} 2](BF 4) 2 (M=Rh, Ir) containing two mutually cis bridging ligands in a HT disposition. Addition of [AuCl(tht)] to [MCl(cod)(Ph 2PBzIm)] gave the heterometallic complexes [MCl(cod)(μ-Ph 2PBzIm)AuCl] with the gold atom coordinated to the P-end. While the Ir–Au compound remained as such in solution, the Rh–Au complex was found to be in equilibrium with [AuCl(Ph 2PBzIm)] and [{Rh(μ-Cl)(cod)} 2]. Reaction of trans-[RhCl(CO)(Ph 2PBzIm) 2] with [{Rh(μ-Cl)(CO) 2} 2] gave the ‘A-frame’ complex [{RhCl} 2(μ-CO)(μ-Ph 2PBzIm) 2] while the reaction with [PdCl 2(NCMe) 2] resulted in the formation of three isomers of the metal–metal bonded compound [(CO)Cl 2Rh(μ-Ph 2PBzIm) 2PdCl].