Carbon Atom Insertion: A One-Step Synthesis of Tricyclo[3.2.1.0^2,7]octanes and Tricyclo[4.1.0.0^2,7]heptanes from Cyclohexenes¹

Abstract

Reinarz and Fonken have reported² that the dibromocarbene adduct (1) of 1-methylcyclohexene, upon reaction with methylllthium at 0° in ether, produced exclusively the bicyclobutanes 2 and 3 in relative yields of 60% and 40%, respectively. We have prepared 1 by the phase-transfer method³ of Makosza and Fedorynski in a yield of 67%, found these previous results to be completely reproducible in our hands, and determined the combined yield of the two products (2 and 3) to be 67% also. Thus, the overall