摘要 : Urea/thiourea have been identified as an effective ammonia surrogate in the construction of quinazolin-4(3H)-one ring. This strategy afforded a simple and catalystfree synthesis of 2-substituted 2,3-dihydroquinazolin-4(1H)-ones an... 展开 Urea/thiourea have been identified as an effective ammonia surrogate in the construction of quinazolin-4(3H)-one ring. This strategy afforded a simple and catalystfree synthesis of 2-substituted 2,3-dihydroquinazolin-4(1H)-ones and quinazolin-4(3- H)-ones via the reaction of isatoic anhydride and aryl aldehydes in the presence of urea or thiourea in ethanol. The reaction proceeded well to afford the quinazolin-4(3H)-one or its dihydro derivative, depending on the nature of carbonyl compounds employed. 收起