... Department of Chemistry, Faculty of Science, Kyoto University, Kyoto 606, Japan ... in the presence of azobis(isobutyronitri1e) (AIBN, 0.3 equiv) at 80 "C for 1-2 h., This reaction is now being used as a useful strategy for organic synthe ~ is ... 5) (a) Ono, N.; Miyake, H.; Kaji, A. J. Chem ...