Synthesis and reactions of heterodinuclear organopalladium–cobalt complexes acting as copolymerization catalyst for aziridine and carbon monoxide
作者:Shin-ichi Tanaka、Hideko Hoh、Yoshifumi Akahane、Susumu Tsutsuminai、Nobuyuki Komine、Masafumi Hirano、Sanshiro Komiya
DOI:10.1016/j.jorganchem.2006.04.044
日期:2007.1
A series of heterodinuclear acylpalladium-cobalt complexes having a bidentate nitrogen ligand, L-2(RCO)Pd-Co(CO)(4) (L-2 = bpy, R = Me (5), Ph (6); L-2 = tmeda, R = Me (7), Ph (8); L-2 = phen, R = Me (9), Ph (10)) are prepared by metathetical reactions of PdRIL2 with Na+[Co(CO)(4)](-) followed by treatment with CO. These complexes are characterized by NMR and IR spectroscopies and elemental analyses, and the molecular structures of 6, 8, and 9 are determined by X-ray structure analysis. Geometry at Pd is essentially square planar and the Cc atom is considered to have d(10) tetrahedral structure, where cobalt(-I) anion coordinates to palladium(II) cation. Heterodinuclear organopalladium-cobalt complexes are shown to catalyze copolymerization of aziridines and CO under mild conditions. Reaction of (dppe)MePd-Co(CO)(4) (1) with aziridine gives a cationic (aziridine)palladium(II) complex with [CO(CO)(4)](-) anion, [PdMe(aziridine)(dppe)](+)[CO(CO)(4)](-) (13). (c) 2006 Elsevier B.V. All rights reserved.