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.