Facile Ecofriendly Synthesis of Monastrol and Its Structural Isomers via Biginelli Reaction

In this paper, a Q-tube equipment is proposed as a valid alternative to monomode MW technology to synthesize in a simple and economic way a library of dihydropyrimidine derivatives performing the Biginelli reaction in solvent-free conditions under pressure and with the catalysis of a very mild and environmentally benign Lewis acid consisting of erbium trichloride hexahydrate.