Eco-friendly syntheses of 2,2-disubstituted- and 2-spiroquinazolinones

Abstract

Environmentally friendly methods were applied to prepare quinazolin-4(1H)-one derivatives in either aqueous or solventless medium from anthranilamide and a number of ketones. With dialkyl-substituted ketones, acetophenone and cycloalkanones, the ring closure proceeded smoothly under either aqueous or solventless conditions. With poorly water-soluble cycloalkanones, the ring closure was carried out under mechanochemical ball-milling conditions, in the presence of molecular iodine as catalyst. The environmentally friendly protocols applied resulted in the corresponding quinazolinones in quantitative yields.