Rhodium(III)-mediated oxime–nitrile coupling giving chelated iminoacylated species†
Abstract
Treatment of the acetonitrile complex mer-[RhCl3(MeCN)3] with cyclopentanone oxime (C4H8)CNOH resulted in the formation of two rhodium(III) products that contain newly formed chelated iminoacyl ligands, i.e. [RhCl3{NHC(Me)ONC(C4H8)}{HONC(C4H8)}] and [RhCl2{NHC(Me)ONC(C4H8)}2]Cl·1.5H2O. Only one iminoacylated product, i.e. the rhodium(III) complex [RhCl2{NHC(Ph)ONC(C4H8)}2]Cl·H2O·EtOH, has been isolated in the reaction between the oxime and the benzonitrile complex mer-[RhCl3(PhCN)3] in ethanol. A formally reverse reaction between [RhCl3{HONC(C4H8)}3], prepared on treatment of RhCl3·4H2O with the oxime in EtOH, and free organonitrile has also been carried out. All products were characterized by elemental analyses (C, H, N, Cl, Rh), FAB+-MS, IR, 1H and 13C-{1H} NMR spectroscopies. X-Ray single-crystal analyses were performed for [RhCl3{NHC(Me)ONC(C4H8)}{HONC(C4H8)}], [RhCl2{NHC(Me)ONC(C4H8)}2]Cl·1.5H2O, [RhCl2{NHC(Ph)ONC(C4H8)}2]Cl·H2O·2EtOH and mer-[RhCl3{HONC(C4H8)}3].