Ni-catalyzed nucleophilic conjugate additions of Grignard and organozincate reagents to substituted 4-vinylpyridines. General synthesis of phosphodiesterase IV inhibitors

Alkyl, aryl, and vinyl Grignard reagents were added to olefin II under Ni(acac)2 or Cl2Ni(PPh3)2 catalysis to give products with the general formula I in 74–95% yield. Organozincates gave similar results with Ni(acac)2 as the catalyst.