Sodium Dithionite-Initiated Coupling of 1-Bromo-1-chloro-2,2,2-trifluoro­ethane with Pyrroles: A New, Convenient and Economical Synthesis of 5-(Trifluoromethyl)dipyrromethanes

Abstract

Sodium dithionite-initiated reactions of pyrrole and 1-methylpyrrole with 1-bromo-1-chloro-2,2,2-ethane in an acetonitrile-water mixture provide the respective 5-(trifluoromethyl)di­pyrromethanes 1 and 3 as main products in 40-58% isolated yields and of high purity. Small amounts of tripyrranes 2 and 4 are also formed and could be isolated from the reaction mixtures.

Key words

5-(trifluoromethyl)dipyrromethanes - pyrroles - 1-bromo-1-chloro-2,2,2-trifluoroethane - sodium dithionite

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Dmowski, W.; Ignatowska, J. J. Fluorine Chem., in press.