Triethylamine → (S)-2-(tert-butoxycarbonylamino)-3-cyclohexylpropyl methanesulfonate

Participants

Reaction Conditions

Reaction Steps

A solution of tert-butyl (S)-3-cyclohexyl-1-hydroxypropan-2-ylcarbamate (3.02 g, 11.7 mmole) in CH2Cl2 (50 mL) and triethylamine (4.0 mL, 28.6 mmol) was cooled to −20° C. (internal temperature). Neat methanesulfonyl chloride (2.0 mL, 25.7 mmol) was added dropwise, maintaining the internal temperature at −20° C. (+/−5° C.). The reaction mixture was stirred at −20° C. for an additional 30 min and at 0° C. for 1 h. Reaction progress was followed by TLC and LC-MS. The reaction was quenched with ice-cold water, extracted with CH2Cl2 (3×20 mL), washed with water (3×10 mL), dried (Na2SO4), decanted, and stripped to give 4.13 g (quant) of product. 1H NMR (CDCl3) δ 0.80-1.40 (10H), 1.40 (s, 9H), 1.65 (t, 2H), 1.75 (d, 1H), 2.95 (s, 3H), 3.94 (m, 1H), 4.10 (m, 1H), 4.24 (m, 1H), 4.60 (m, 1H). MS ESI+ve m/z 236 (M(−BOC)+1).

Provenance & Evidence