Abstract

Protonation of the highly reactive 1:1 intermediates, produced in the reaction between triphenylphosphine and dialkyl acetylenedicarboxylates by 2,2,2-trifluoroethanol, leads to vinyltriphenylphosphonium salts, which undergo Michael addition reaction with conjugate base to produce the corresponding fluorine-containing stabilized phosphorus ylides. Intermolecular Wittig reaction of the fluorine-containing stabilized phosphorus ylides with ninhydrin leads to the corresponding highly electron-poor fluorine-containing alkenes.