A Microwave-Assisted and Heteropolyacids-Catalysed Cyclocondensation Reaction for the Synthesis of4(3H)-Quinazolinones

摘要

We have investigated a microwave–assisted synthesis of 4(3H)–quinazolinones by condensation of anthranilic acid, orthoesters (or formic acid) and substituted anilines, using Keggin-type heteropolyacids (H3PW12O40∙13H2O, H4SiW12O40∙13H2O, H4SiMo12O40∙13H2O or H3PMo12O40∙13H2O) as catalysts. We found that the the use of H₃PW₁₂O₄₀∙13H₂O acid coupled to microwave irradiation allows a solvent-free, rapid (~13 min) and high-yielding reaction.