A SIMPLE,EFFICIENT AND NEW METHOD FOR PREPARING AZO UREAS

Azo compounds are widely utilized as dyes and analytical reagents.They can also be used as materials for non-linear optics and for storage optical information in laser dish^[1]. Recently, many noteworthy studies have shown that azobenzene derivatives possess excellent optical memory and photoelectric properties^[2]. The preparation of ordinary azo compounds has been described in many references. However, those compounds generally bear alkyl or aryl groups on both sides of the azo linkage (-N=N-).