A solvent-free reaction between urea/thiourea, dimedone and aromatic aldehydes in the presence of catalytic amounts of zirconium (IV) oxychloride octahydrate (ZrOCl 2 .8H 2 O) as a powerfull Lewis acid leads to octahydroquinazolinone/thione derivatives in good yields. This method has advantages such as avoidance of the organic solvents, production of pure products without any by-product, short reaction times and simple operation.

Abstract. An environmentally friendly and clean procedure gives octahydroquinazolinones/thiones by a simple Biginelli condensation of urea/thiourea, aromatic aldehydes, and cyclic 1,3-diones in the presence of indium(III) trifluoromethanesulfonate (In(OTf) 3 ) in solventless conditions. This method has advantages such as avoidance of the organic solvents, high yield of pure products without any by-product, short reaction times and operational simplicity.(doi: 10.5562/cca2087)

The introduced method leading to quinazolinones (IV) and (VI) and thiones (VIII) has advantages such as avoidance of organic solvents, high yields of pure products, short reaction times, and operational simplicity.