green and efficient synthesis of azo schiff bases

pure azo schiff bases were readily and conveniently accessible in high yields by mixing of the reagents either as aqueous slurry, or by grinding at room temperature. this method, unlike a classical method, needs neither harsh conditions nor organic solvents. the satisfactory results were obtained with excellent yields, short reaction time, and operational simplicity in the experimental procedure. comparison of time and yield in this green method with the classical methods is also performed.