An efficient synthesis of 1,2-dihydro-1-aryl-3H-naphth[1,2-e][1,3]oxazin-3-one derivatives catalysed by 1,3-dibromo-5,5-dimethylhydantoin/kaolin under solvent-free conditions

摘要

A mild and efficient method has been developed for the preparation of 1,2-dihydro-1-aryl-3H-naphth[1,2-e][1,3]oxazin-3-one deriyatives from the reaction of aromatic aldehydes with beta-naphthol and urea in the presence of 1,3-dibromo 5,5-dimethylhydantoin (DBH), as an efficient, inexpensive catalyst under thermal and solvent-free conditions. Good yields, short reaction times, straightforward workup, and green conditions are the most obvious advantages of this procedure.