Reactions of tetracyanoethylene with polyenes]

Reactions of tetracyanoethylene with polyenes have been studied. With vitamin A derivatives 7,10- and 11,14-cycloadducts were formed. Starting with the unsaturated dihydroxy compound 13 tetracyanoethylene first catalyzed the ring closure to give the dihydrofuran 14 which then was dehydrogenated to the corresponding furan 15 .