Sodium borohydride → 3-Hydroxy-2,8-dimethyl-1-oxa-8-azaspiro[4.5]decane

Participants

Reaction Steps

To a solution of 2,8-dimethyl-1-oxa-8-azaspiro[4.5]-decan-3-one (200 mg) in 7 ml ethanol, was added 25 mg sodium borohydride at room temperature, and the mixture was stirred at room temperature for two hours. The reaction mixture was cooled in an ice-water bath, acidified by addition of 6N--HCL (to about pH 4), and stirred for about 20 minutes with the ice-water bath removed. Ethanol was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography by using, as eluent, a mixed solvent of chloroform/methanol/conc. ammonia (5:1:0.1 by volume), giving 200 mg of 3-hydroxy-2,8-dimethyl-1-oxa-8-azaspiro[4.5]decane as oil. It was dissolved in ether, and ehtanolic hydrogen chloride was added to this solution, thus giving its hydrochloride as white crystals.

Provenance & Evidence