4-(3-bromo-4-fluoro-phenyl)-6,6-dimethyl-5-oxo-2-propyl-4,5,6,8-tetrahydro-1H-pyrano[3,4-b]pyridine-3-carboxylic acid methyl ester 在
吡啶 、 pyridinium hydrobromide perbromide 作用下,
以
氯仿 为溶剂,
反应 0.58h,
生成 (+)-trans-9-(3-bromo-4-fluorophenyl)-3-ethyl-7,7-dimethyl-5,9-dihydro-3H,4H-2,6-dioxa-4-azacyclopenta[b]naphthalene-1,8-dione