Ammonium Chloride → cis-4-(Boc-amino)-1-methylcyclohexanol

Participants

Reaction Steps

To a stirred solution of tert-butyl 4-oxocyclohexylcarbamate (2 g, 9.3 mmol) in THF (40 mL) at −78° C. was added dropwise MeMgBr (10 mL of 3M/THF, 30 mmol). The reaction mixture was allowed to warm to room temperature. After stirring at room temperature for 18 h, the reaction was treated with saturated NH4Cl aqueous solution. The solution was concentrated, taken up into CH2Cl2, washed with H2O by aid of citric acid. The organic phase was washed with saturated NaHCO3 aqueous solution, H2O, brine, dried (Na2SO4) and concentrated. The crude product was purified by column chromatography to give tert-butyl 4-hydroxy-4-methylcyclohexylcarbamate 2 as oil (1.2 g, 56%). 1H NMR (300 MHz, CDCl3) δ 1.20 (s, 3H), 1.45 (s, overlapped 9H), 1.5˜1.8 (set of m, 10H), 3.40 (br, 1H), 4.40 (br, 1H).

Provenance & Evidence