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.