view:20506 Last Update: 2019-1-30
Ali Ramazani; Ebrahim Ahmadi; Ali Reza Kazemizadeh; Leila Dolatyari; Nader Noshiranzadeh; Issa Eskandari; Ali Souldozi|
One-Pot, Three-Component Synthesis of Dialkyl 1,2-Dihydroquinoline-2,3-Dicarboxylates from Triphenylphosphine, Acetylenic Esters, and Amide Derivatives of 2-Aminobenzaldehyde in Aqueous Acetone
Protonation of the highly reactive 1:1 intermediates, produced in the reaction between triphenylphosphine and dialkyl acetylenedicarboxylates by amide derivatives of 2-aminobenzaldehyde in the mixture of acetone-water (3:1) leads to vinyltriphenylphosphonium salts, which undergo a Michael addition reaction with a conjugate base to produce the corresponding stabilized phosphorus ylides. An intramolecular Wittig reaction of the stabilized phosphorus ylide group with the aldehyde group leads to the corresponding dialkyl 1,2-dihydroquinoline-2,3-dicarboxylates.