Straightforward synthesis of quinazolin-4(3)-ones visible light-induced condensation cyclization

A green, simple and efficient method is developed for the synthesis of quinazolin-4(3 H )-ones via visible light-induced condensation cyclization of 2-aminobenzamides and aldehydes under visible light irradiation. The reaction proceeds using fluorescein as a photocatalyst in the presence of TBHP without the need for a metal catalyst. In addition, this reaction tolerates a broad scope of substrates and could afford a variety of desirable products in good to excellent yields. Thus, the present synthetic method provides a straightforward strategy for the synthesis of quinazolin-4(3 H )-ones. Visible light was used as a readily available and renewable clean energy source for the green and metal catalyst free synthesis of quinazolin-4(3 H )-ones. High and excellent yields of the desired products were obtained with good functional group tolerance.