Abstract
Protonation of the highly reactive 1:1 intermediates, produced in the reaction between triphenylphosphine and dialkyl acetylenedicarboxylates, by 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione leads to vinyltriphenylphosphonium salts, which undergo Michael addition reaction with conjugate base to produce corresponding thiophene-containing phosphorus ylides. Basic alumina powder was found to catalyze conversion of the phosphorus ylides to dialkyl 2-[2-oxo-2-(2-thienyl)ethyl]-3-(1,1,1-triphenyl-λ 5-phosphanylidene)succinates in solvent-free conditions under microwave (0.9 KW, 3 min) and thermal (25°C, 120 min.) conditions.
Acknowledgments
This work was supported by the Zanjan University.