Addition of diphenylphosphine to Michael-type olefins: the preparation of phosphine-nitrile and phosphine-ester ligands

Article abstract of DOI:10.1016/0022-328X(90)87207-T

The reactions of five Michael-type olefins with diphenylphosphine have been carried out. 1-Cyanocyclopentene, 1-cyanocyclohexene, and 4-t-butyl-1-cyanocyclohexene all provide the corresponding 2-diphenylphosphino-1-cyanocycloalkanes, and both methyl acrylate and ethyl methacrylate yield to corresponding 2-diphenylphosphinopropionates.For the products from 1-cyanocyclopentene and 1-cyanocyclohexene, 13C and 31P NMR data are consistent with the formation of both trans (Ph2P equatorial and CN axial) and cis (both Ph2P and CN equatorial) isomers.The morpholine amide of 3-diphenylphosphinopropionic acid has been obtained by treatment of methyl-3-diphenylphosphinopropionate with the dimethylaluminum adduct of morpholine.This phosphine, Ph2Pmorph, has been isolated as its palladium(II) complex, (Ph2Pmorph)2PdCl2.A phosphine-benzaldimine, Ph2P(CH2)3NC(H)C6H5, has been obtained by reacting Ph2P(CH2)3NH2, from the reduction of PhP(CH2)2CN, with benzaldehyde in the presence of molecular sieves.