SYNTHESIS OF ATTRACTANTS FOR ORIENTAL FRUIT-FLY DACUS-DORSALIS HENDELUSING A CATALYTIC ORGANOCOPPER COUPLING REACTION

A general synthetic approach to various catechol derivatives was devel oped using a copper-catalyzed cross-coupling reaction of 1,2-dimethoxy -4-bromomethyl, 1-ethoxy-2-methoxy-4-bromomethyl- and 2-ethoxy-1-metho xy-4-bromomethylbenzenes with Grignard reagents. Dilithium tetrachloro cuprate was an acceptable catalyst in the dimethoxy series, whereas co pper(I) iodide in THF-HMPA was a superior catalyst in all cases due to decreased side reactions, i.e., reduction and reductive coupling. Met hyl-substituted analogs of methyl eugenol, a potent attractant of Orie ntal fruit fly, Dacus dorsalis Hendel, were synthesized by this method and evaluated for attractancy in held tests.