Herein we report a convenient and efficient synthesis of 2-Arylbenzoxazole from the Schiff’s bases of 2-Aminophenol, 3, 5-Diarylisoxazole from α , β -unsaturated ketoxime and 1,3,5-Triarylpyrazole from 2-pyrazoline and N-Arylhydra zone by using milder, less toxic and less expensive-NBS-SiO 2 , KMnO 4 -Al 2 O 3 , PCC-SiO 2 and ACC-Al 2 O 3 as solid- supported oxidizing agents at room temperature. Within the framework of Green Chemistry, the use of solid supported reagents has many advantages such as 1 ) they are easy to remove from reactions by filtration 2 ) excess reagents can be used to drive the reaction without introducing any difficulties in purification 3 ) such solid-supported reagents react dif ferently, mostly more selectively, than their unbound counterparts and 4 ) toxic, noxious and explosive chemicals are handled more safely when contained on solid support.
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