Phosphinoalkylnitrile: Synthese und Koordinationsverhalten an Palladiumzentren Phosphinoalkylnitnles: Synthesis and Coordination Behaviour at Palladium Centres

Phosphinoalkylnitriles, Phosphine Complexes of Palladium, Crystal Structure, Catalysis, -Lactones Phosphinoalkylnitriles R2P-(CH2)„-CN {R = isopropyl ('pr), phenyl (ph), cyclohexyl (‘ hex), n 3, 6, 10} have been prepared starting from the corresponding secondary phosphines in an easy three step synthesis. All new compounds were characterized by their 'H -, i3C and 31P NMR data. Some of these new P, N ligands were used to prepare complexes [{R2P(CH2)„-CN}2PdCl2] which were also identified by their NMR data. In addition the crystal structures of three derivatives, [{'pr2P-(CH2)3-CN}2PdCl2] 7a, [{ph2P-(CH2)3-CN}2PdCl2) 7b and [{ph2P-(CH2)6-CN}2PdCl2] 8b were determined by X-ray analysis. The coordination mode of the phosphinoalkylnitriles in these complexes was found to be P-bonded resulting in a trans configuration. Palladium catalysts with 5a as ligand show high activies in the co-oligomerization of butadiene and carbon dioxide. The ^-lactone 11a is formed under very mild conditions.