Platinum Complexes with picoline-functionalized benzimidazolin-2-ylidene ligands

Abstract

The dicarbene platinum complexes of the type [Pt(L)2]Br 2 [5]Br2-[8]Br2 (L = N-alkyl-́- picolylbenzimidazolin-2-ylidene) have been prepared by two different methods. The in situ depro-tonation of picoline-functionalized benzimidazolium salts 1-4 with platinum acetylacetonate gave the platinum complexes [5]Br 2-[8]Br2 in good yields. Complex [8]Br2 has also been obtained by a ligand transfer reaction from the silver dicarbene complex [9][AgBr2]. Attempts to cystallize [8]Br2 obtained from the carbene transfer reaction led to the isolation of the previously undetected mono-carbene complex Pt(Cl) 2L (10) which contains only one picoline-functionalized carbene ligand coordinating in a chelating fashion to the metal center. © 2010 Verlag der Zeitschrift fiir Naturforschung.