New facile and solvent-free method for the one-pot synthesis of quinazolin-4(3H)-ones catalyzed by SbCl3 under microwave irradiation

Efficient and fast condensation of anthranilic amide or anthranilic acid with various orthoesters have been carried out using a catalytic amount of antimony(iii) chloride (sbcl3) under microwave irradiation to afford a series of 2-substituted quinazolin-4(3h)-ones in good to excellent yields under solvent free condition. the reactions have been operated without solvent by one-pot reaction only in several minutes and the reactions have been optimized,such as microwave irradiation power and catalyst charge. furthermore,ammonium acetate as a nitrogen source in the condition of anthranilic acid is very convenient. its simplicity,efficiency,mild reaction conditions,high yields of products,easy workup procedure and good generality,make this one-pot procedure interesting for the preparation of different kinds of substituted quinazolin-4(3h)-ones. one of the important features of this methodology is the use of a minimum amount of sbcl3 as an effective lewis acid catalyst and the avoidance of hazardous organic solvent. � 2016,chemical society of pakistan. all rights reserved.