Influence of an Internal Trifluoromethyl Group on the Rhodium(II)-Catalyzed Reactions of Vinyldiazocarbonyl Compounds

Incorporation of a trifluoromethyl group into the structure of 4-(alkoxycarbonyl)­vinyldiazocarbonyl compounds greatly decreases the tendency of the carbenoid intermediates formed during Rh­(II)-catalyzed reactions to undergo intermolecular processes. Instead, they are prone to experience intramolecular [1,5]- and [1,3]-electrocyclizations to produce reactive cyclopropenes and furans, and these are capable of further transformations.