Hydrochloric Acid → (1S,5S)-5-amino-2,2-dimethylcyclohexanol hydrochloride

Participants

Reaction Steps

To a mixture of 2-((1R,3R)-3-hydroxy-4,4-dimethylcyclohexyl)isoindoline-1,3-dione and 2-((1S,3S)-3-hydroxy-4,4-dimethylcyclohexyl)isoindoline-1,3-dione (1.1 g, 4.02 mmol) in ethanol (50 mL) was added hydrazine hydrate (0.195 mL, 4.02 mmol). The resulting solution was allowed to stir at reflux overnight under a nitrogen atmosphere. The reaction was cooled to ambient temperature and then the pH was adjusted to <2 via addition of concentrated aqueous hydrochloric acid. The precipitate was filtered off, rinsed with ethanol, and then the resulting filtrate was concentrated to 20 mL under reduced pressure. An equal volume of water was added and this mixture was stirred at ambient temperature for 15 min. The solids were filtered off, rinsed with water, and the filtrate was concentrated under reduced pressure to give a solid that was dried in a vacuum oven for a few hours to afford a mixture of (1R,5R)-5-amino-2,2-dimethylcyclohexanol hydrochloride and (1S,5S)-5-amino-2,2-dimethylcyclohexanol hydrochloride (835 mg, 4.65 mmol, 115% yield) that was used without further purification. 1H NMR (400 MHz, DMSO-d6) δ ppm 7.87-8.21 (m, 3H), 2.98-3.23 (m, 1H), 2.75-3.02 (m, 1H), 1.49-1.92 (m, 2H), 1.26-1.47 (m, 3H), 0.96-1.16 (m, 1H), 0.48-0.93 (m, 6H)

Provenance & Evidence