Asymmetric hydrovinylation of unactivated linear 1,3-dienes

J Am Chem Soc. 2010 Mar 17;132(10):3295-7. doi: 10.1021/ja1004703.

Abstract

Monosubstituted acyclic (E)-1,3-dienes undergo efficient hydrovinylation giving (Z)-3-alkylhexa-1,4-dienes upon treatment with catalytic amounts of bidentate phosphine-CoCl(2) complexes {[P~P](CoCl(2))} and Me(3)Al in an atmosphere of ethylene. The regioselectivity of the reaction (i.e., 1,4- or 1,2-addition) depends on the nature of the ligand and temperature at which the reaction is carried out. Complexes derived from (RR)-DIOP and (SS)-BDDP at -45 degrees C give very high enantioselectivities for several prototypical 1,3-dienes. In sharp contrast to the corresponding Ni(II)-catalyzed hydrovinylation, 1-aryl-substituted 1,3-dienes give almost exclusively achiral linear 1,4-addition products, unless the 2-position is also substituted. Solid-state structures of the precatalysts are presented.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Alkadienes / chemical synthesis*
  • Alkadienes / chemistry
  • Catalysis
  • Cobalt / chemistry
  • Phosphines / chemistry
  • Vinyl Compounds / chemical synthesis*

Substances

  • Alkadienes
  • Phosphines
  • Vinyl Compounds
  • Cobalt
  • cobaltous chloride