4-Hydroxy-2-quinolones. 118. Synthesis, structure, and chemical properties of 2-bromomethyl-5-oxo-1,2-dihydro-5H-oxazolo-[3,2-a]quinoline-4-carboxylic acid and its ethyl ester
Bromination of N-allyl-substituted 4-hydroxy-2-quinolinones with molecular bromine in acetic acid or carbon tetrachloride occurs with closing of a five membered oxazole ring to give 2-bromomethyl-5-oxo-1,2-dihydro-5H-oxazolo[3,2-a]quinoline.