SYNTHESE D'ALCOHOLS α-ALLENIQUES PAR REACTION D'ORGANOCHROMIQUES PROPARGYLIQUES SUR LES ALDEHYDES ET LES CETONES

Article abstract of DOI:10.1016/S0040-4020(01)92452-4

Propargylic bromides can be condensed with aldehydes and ketones in the presence of Hiyama's reagent (2CrCl3+LiAlH4 in THF) leading to α-allenic alcohols, to homopropargylic alcohols or to the mixture of both of them.The selectivity (or specificity) of this reaction depends on the substitution of the propargylic bromide, on the structure of the ketone, and on the presence of HMPT in the reaction mixture.In many cases, α- allenic alcohol has been specifically or very selectively obtained.The mechanism of the reaction and the influence of the various parameters are discussed.