Nucleophilic 5-endo-trig Cyclization of 3,3-Difluoroallylic Metal Enolates and Enamides: Facile Synthesis of Ring-Fluorinated Dihydroheteroles

Abstract

Metal enolates and enamides bearing difluoroallylic moieties underwent nucleophilic 5-endo-trig cyclization, a process considered to be disfavored according to Baldwin’s rules. Whereas no C-cyclization was observed in these reactions, O- and N-cyclization proceeded exclusively to afford 5-fluorinated 2-alkylidene-2,3-dihydrofurans and -2,3-dihydropyrroles, respectively.

Key words

cyclizations - fluorine - heterocycles - furans - pyrroles - ring closure

• References


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