Solvent-free synthesis of 1,2-disubstituted 1,2-dihydroisoquinolines

One-pot and ef?cient approach to the synthesis of dialkyl 2-[1-[(alkoxycarbonyl)anilino]-2(1H)-isoquinolinyl]-2-butenedioates is described. This method involves three component reaction between isoquinoline, dialkyl acetylenedicarboxylate and N-phenyl carbamates under solvent-free condition, without using any catalyst and at room temperature. The mild reaction conditions and high yields of the products exhibit the good synthetic advantage of this method.