відсутність розчинника

Salicylic Acid as a Bio-Based, Natural and Versatile Catalyst for Green, Solvent-Free and One-Pot Biginelli Synthesis of 3,4-Dihydropyrimidin-2-(1H)-one/thione Derivatives

A green synthetic route for eco-safe and solvent-free preparation of biologically active 3,4-dihydropyrimidin-2-(1H)-ones/thiones derivatives via one-pot, three-component Biginelli condensation reaction of β-keto esters (methyl or ethyl acetoacetate), aromatic aldehyde (benzaldehyde derivatives) and urea or thiourea have been developed using a salicylic acid as a bio-based, natural and versatile catalyst.