Sodium Azide → (S)-tert-butyl 1-azido-3-cyclohexylpropan-2-ylcarbamate

Participants

Reaction Conditions

Reaction Steps

(S)-2-(tert-Butoxycarbonylamino)-3-cyclohexylpropyl methanesulfonate (13.3 g, 39.3 mmol) from Step 1 was dissolved in anhydrous DMF (140 mL). Solid NaN3 (5.18 g, 79.7 mmol) was added and the reaction was warmed to 50° C. for 5 h. The reaction mixture was permitted to cool to rt and the solvent was removed under reduced pressure (150 Torr, 55° C.). This material was taken up into Et2O (150 mL), washed with water (3×10 mL) and brine (3×10 mL), dried (Na2SO4), decanted, and stripped to give 13.9 g crude product. This was separated on a silica column using a gradient from 0-100% EtOAc in hexanes. Solvent was stripped from appropriate fractions to give (S)-tert-butyl 1-azido-3-cyclohexylpropan-2-ylcarbamate (7.21 g, 65%) as a clear oil. 1H NMR (CDCl3) δ 0.60-1.80 (m 12H), 1.40 (s, 9H), 2.86 (d, 1H), 3.29 (d, 1H), 4.85 (d, 1H), 4.51 (m, 1H), 8.00 (s, 1H). MS ESI+ve m/z 183 (M(−BOC)+1).

Provenance & Evidence