GaCl₃-Catalyzed α-Ethenylation Reaction of Ketone

Abstract

In the presence of catalytic amounts of GaCl₃ (10 mol%) and 2,6-di(t-butyl)-4-methylpyridine (10 mol%), five- or six-membered ring ketones possessing α,α′-disubstituents are ethenylated at the α-carbon with triethylsilylethyne at 180 °C. The roles of the base are to inhibit decomposition of the products and to promote protodegallation of the organogallium intermediates.

Keywords

catalytic reaction - α-ethenylation - GaCl₃ - cyclic ketone - silylethyne

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