Sulfuric Acid → 2,2,6,6-Tetramethyl-4-hydroxy-4-tert.-butylcarbamoyl piperidine

Reaction equation

[CH3:1][C:2]1([CH3:13])[CH2:7][C:6]([OH:10])([C:8]#[N:9])[CH2:5][C:4]([CH3:12])([CH3:11])[NH:3]1.[C:14](O)([CH3:17])([CH3:16])[CH3:15].S(=O)(=O)(O)[OH:20]>C(O)(=O)C>[CH3:1][C:2]1([CH3:13])[CH2:7][C:6]([OH:10])([C:8](=[O:20])[NH:9][C:14]([CH3:17])([CH3:16])[CH3:15])[CH2:5][C:4]([CH3:12])([CH3:11])[NH:3]1

Participants

Procedure

54.6 g 2,2,6,6-Tetramethyl-4-hydroxy-4-cyanopiperidine together with 45 g tert.-butanol in 200 ml glacial acetic acid are introduced into the reactor. Subsequently, 60 g concentrated sulfuric acid are added dropwise with agitation, and agitation is continued for 2 hours at 70° C., thus forming a precipitate which is filtered off and dissolved in water. On alkalization with NaOH, the product precipitates, it is suction-filtered and recrystallized from ethyl acetate. Yield 44 g, m.p. 134°-136° C.