反应详情

Prepared by the method described in Example 1 except that the 3,4-dimethoxyphenol (61.5 g, 0.40 moles) is added in one portion to an ice-cooled mixture of ethyl 4-oxo-3-piperidinecarboxylate hydrochloride (75 g, 0.36 moles) and 200 ml of 72% sulfuric acid. Recrystallization from acetonitrile yielded the product (71 g), mp 186°-188° C.

1. customPrepared by the method
2. temperaturecooled
3. customRecrystallization from acetonitrile