3-Hydroxy-5-keto-4-phenylazo-3-cyclohexen-methylcarboxylat 、
乙酰胺 、
3-溴吡咯烷-2,5-二酮 、
溴 在
acetamide; compound with hydrogen bromide 、
乙醇 作用下,
以
氯仿 为溶剂,
反应 0.5h,
以whereby there was obtained 3,5-dihydroxy-4-phenylazo-benzoic acid methyl ester having a melting point of 216°-218° C.的产率得到3,5-Dihydroxy-4-phenylazo-benzoic acid methyl ester