反应详情

16.2 parts of 2,2,6,6-tetramethyl-4-hydroxypiperidine-4-carboxylic acid methyl ester (according to German Patent No. 91,122), 5 parts of hydrazine hydrate and 20 parts of methanol were boiled under reflux for 10 hours and the methanol was subsequently distilled off. The residue was recrystallised from cyclohexane. Yield: 15.3 parts of 2,2,6,6-tetramethyl-4-hydroxypiperidine-4-carboxylic acid hydrazide melting at 121° to 123° C.

1. temperatureunder reflux for 10 hours
2. distillationthe methanol was subsequently distilled off
3. customThe residue was recrystallised from cyclohexane