作者:Jörn Müller、Christian Friedrich、Petra Escarpa Gaede、Sven Sodemann、Ke Qiao
DOI:10.1016/0022-328x(94)88131-6
日期:1994.5
The square-pyramid complexes (eta3-diene)2IrR [R = CH2C6H5, cyclo-C3H5, diene = 2,3-dimethylbuta-1,3-diene (dmb), cyclohexa-1,3-diene (chd); R = C2 H 3, diene = chd] are obtained by treatment of (eta4-diene)2 IrCl with RM (M = MgX, Li). For diene = chd and RM = NaCp, (eta2-chd)2Ir(eta5-Cp) was formed as the first compound with eta2 -bonded cyclohexadiene ligands, and was characterized by X-ray crystal analysis. With an excess of PMe3, (chd)2IrCH2C6H5 undergoes ligand substitution to form (chd)(PMe3)2IrCH2C6H5, whereas the dmb compound does not react. The heterobimetallic complexes (dmb)2IrCH2C6H5Cr(CO)3, as well as (dmb)2IrC6H5M(CO)3 (M = Cr, Mo), have been prepared, whilst attempts to synthesize the corresponding (chd)2IrRM(CO)3 species failed. A general mechanism for the formation of pentacoordinated (eta4-diene)2IrR by treatment of the corresponding halides with carbanions is proposed.