Selenium-catalyzed oxidative carbonylation of 2-aminobenzyl alcohol to give 1,4-dihydro-2 H -3,1-benzoxazin-2-one
文摘
An efficient, economical, and phosgene-free approach was developed for the preparation of 1,4-dihydro-2H-3,1-benzoxazin-2-one from 2-aminobenzyl alcohol. In terms of its key features, this reaction uses the cheap and recyclable non-metal selenium as a catalyst instead of the noble metal palladium; carbon monoxide as a carbonylation agent instead of virulent phosgene or one of its derivatives; and oxygen as an oxidant. The selenium-catalyzed oxidative carbonylation reaction of 2-aminobenzyl alcohol proceeded efficiently in a single pot in the presence of triethylamine to afford 1,4-dihydro-2H-3,1-benzoxazin-2-one in 87% yield. Furthermore, the selenium catalyst was readily recovered and recycled, affording a product yield of 80% after five cycles.