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.
Keywords: Quinazolin-4(3H)-one, Microwave, SbCl3, Solvent-free, Orthoester.
Furthermore, to the best of our knowledge, there is no report of the synthesis of quinazolin-4(3H)-ones catalyzed by SbCl3 under microwave irradiation.
2-aminobenzamide (1) (10 mmol), orthoesters (2) (12 mmol) and catalytic amount of SbCl3 were mixed thoroughly in a microwave reactor equipped with a condenser.
Anthranilic acid (4) (10 mmol), orthoester (2) (12 mmol), ammonium acetate (14mmol) and catalytic amounts of SbCl3 were mixed thoroughly in a microwave reactor, equipped with a condenser.
Different parameters have been studied (reaction time and SbCl3 loading).
The condensation of o-aminobenzamide with triethyl orthoformate (2a) was taken as example to study the impact of microwave power on the condensation catalyzed by SbCl3.
In the absence of SbCl3, the yield of quinazolin-4(3H)-one (3a) is only 17% (Table-2, entry 1).