Unusual Cycloadducts from the Dipolar Cycloaddition of Allenyl Perfluoroalkyl Sulfones to Nitrones

Abstract

Abstract The dipolar cycloaddition reaction of allenyl perfluoroalkyl sulfones ( 1 ) to nitrones ( 2 ) was described. Unlike nonfluorine‐containing allenyl sulfones, 1 reacted readily with 2 in ether at room temperature and unusual zwitterionic cycloadducts ( 3 ) were obtained in good yields due to the strong electron‐withdrawing effect of perfluoroalkyl groups. The structure of 3 was characterized by spectral analyses and X‐ray crystallography.