TRANSPOSITION OXY-COPE ASSISTEE PAR LE TRIFLUOROACETATE MERCURIQUE EN QUANTITE STOECHIOMETRIQUE ET EN QUANTITE CATALYTIQUE

Article abstract of DOI:10.1016/0040-4020(84)85011-5

Tertiary 1,5-hexadien-3-ols are transformed at room temperature into δ-ethylenic ketones in 35-90percent yields under two sets of conditions: treatment with one molar equivalent of mercuric trifluoroacetate followed by demercuration of the intermediate α-mercuro ketone with sodium borohydride; and treatment with 0.2 molar equivalent of the same salt in the presence of one molar equivalent of lithium trifluoroacetate or trifluoromethansulfonate.The reactions are highly stereoselective, the E isomer of the ketone forming 80-95percent of the product.The highest selectivity was observed under the second conditions.