Reaction of Pd(η3-C3H5)2 with cyano-olefins; reductive coupling of allyl groups in the presence of triphenylphosphine

Article abstract of DOI:10.1016/0022-328X(88)80456-X

Pd(η³-C3H5)2 reacts with tetracyanoethylene (TCNE) to give a 1/1 adduct identified as Pd(η³-C3H5)(η¹-C3H5)(TCNE) on the basis of spectroscopic evidence and its behaviour in solution.A similar reaction with fumaronitrile is also described.The complex Pd(η³-C3H5)(η¹-C3H5)(TCNE) reacts with triphenylphosphine to give 1,5-hexadiene and Pd(PPh3)2(TCNE); a mechanism for this reaction is proposed on the basis of low temperature 1H and 31P NMR spectroscopy study of the solution during the reaction.The mechanisms are compared with those for the Pt(η³-C3H5) system.