Room-temperature cyclometallation of amines, imines and oxazolines with [MCl2Cp*]2 (M = Rh, Ir) and [RuCl2(p-cymene)]2

Abstract

N,N-Dimethylbenzylamine, alkyl and aryl imines derived from benzaldehyde, and 2-phenyl-4,4-dimethyloxazoline all undergo cyclometallation with [IrCl₂Cp*]₂ (Cp* = η-C₅Me₅) when treated with NaOAc in dichloromethane at room temperature. The imines are also cyclometallated by [RhCl₂Cp*]₂ under the same conditions whilst only N-alkyl imines are cyclometallated by [RuCl₂(p-cymene)]₂. The role of acetate in the cyclometallation is more than just as a base. X-Ray structures of cyclometallated complexes [MCl{C₆H₄-2-C(H)NCH₂CH₂OMe-κC,N}(η-ring)](M = Ir, Rh ring = Cp*; M = Ru, ring = p-cymene), [MCl{C₆H₄-2-C(H)NCH₂CH₂OMe-κC,N}Cp*](M = Ir, Rh), [RuCl(η²-O₂CMe)(p-cymene)] and [IrCl₂(NH₂Ph)Cp*] are reported.