Studies on organic fluorine compounds. XXII. Synthesis and reactions of (trifluoromethyl)benzofurans.

Abstract

2- and 3-(Trifluorometyl) benzofurans (III and V) were synthesized by the reaction of 2-and 3-bromobenzofurans with trifluoromethyliodide in the presence of copper powder. Reaction of III and V with alcoholic sodium hydroxide, lithium aluminum hydride, and sodium amide showed that the trifluoromethyl group on the benzofuran ring is much less reactive than that on the indole ring. The remarkable point of reactions of the (trifluoromethyl) benzofurans is the addition of the nucleophile of C2, C3-double bond, which might be ascribed to the localization of the double bond.