Hydrochloric Acid → HCID 22101549, compound

Participants

Reaction Conditions

Reaction Steps

To an ethanol solution (5 ml) containing the 4-(1,4-dioxa-8-aza-spiro[4.5]decan-8-yl)-5-hydroxy-2,6,6-trimethyl-2-cyclohepten-1-one obtained in Example 26 (1 g, 3.24 millimoles) there was added 6N hydrochloric acid (2 ml), and the mixture was stirred at 75° C. for 4 hours. The reaction solution was concentrated, water was added, and a 1N aqueous sodium hydroxide solution was used for neutralization. The aqueous solution was subjected to extraction with ethyl acetate and drying over anhydrous magnesium sulfate. The crude product obtained by concentration of the ethyl acetate solution was recrystallized from a benzene-hexane mixed solvent to obtain 0.53 g (60.9%) of 4-(4-oxopiperidino)-5-hydroxy-2,6,6-trimethyl-2-cyclohepten-1-one as colorless crystals.

Provenance & Evidence