Synthesis 2011(4): 662-668  
DOI: 10.1055/s-0030-1258408
PAPER
© Georg Thieme Verlag Stuttgart ˙ New York

Substrate-Controlled Regioselective Cobalt(I)-Catalysed 1,4-Hydrovinylation Reactions

Gerhard Hilt*, Stefan Roesner
Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße, 35043 Marburg, Germany
Fax: +49(6421)2825677; e-Mail: Hilt@chemie.uni-marburg.de;
Further Information

Publication History

Received 23 November 2010
Publication Date:
18 January 2011 (online)

Abstract

The substrate-directed regiochemistry of the cobalt-catalysed­ 1,4-hydrovinylation reaction is described. A variety of symmetrical and unsymmetrical 2,3-disubstituted 1,3-dienes are synthesised by ruthenium-catalysed enyne metathesis, and then reacted with a terminal alkene catalysed by cobalt(II) bromide-[1,2-bis(diphenylphosphino)ethane] [CoBr2(dppe)] under reductive conditions. The regiochemistry of the branched 1,4-diene products is influenced by the nature of the substituents on the unsymmetrical 2,3-disubstituted 1,3-dienes. The influence of steric and electronic effects is also discussed.