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Abstract: In this paper, we presented a novel method for the facile and efficient one-pot synthesis of 2-Arylbenzoxazoles, which were directly synthesized from 2-Aminophenol and aldehydes catalyzed by hydrogen tetrachloroaurate (HAuCl₄·4H₂O) under an oxygen atmosphere with anhydrous tetrahydrofuran (THF) as solvent or in solvent-free condition. The results show that this method could bring excellent yields as high as 96%. THF was proven to be the best choice among several solvents screened and the reaction was tolerated with a variety of aromatic aldehydes possessing electron-donating or withdrawing groups. The advantages of the present method lie in catalytic process using economic and environmentally benign dioxygen as oxidant.

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