A straightforward synthesis of polyendiynes is described. The method is based upon a simple dimerization reaction of silylated enynes in the presence of copper salts. A variety of polyunsaturated compounds have been obtained in high yields and with high retention of configuration. (C) 1998 Elsevier Science S.A. All rights reserved.
An efficient stereoselective approach to silylated polyunsaturated γ-alkylidene butenolides
synthetic approach to a variety of polyunsaturated γ-alkylidenebutenolides has been developed, starting from readily available silylated and polyunsaturated terminal alkynes. The palladium-catalysed tandem cross-coupling/cyclization reaction of the alkynes with the (Z)-3-iodo-2-propenoic acid leads directly to polyunsaturated (Z)-γ-alkylidene butenolides with a high degree of stereoselectivity.