1-Ethyl-3-(3'-dimethylaminopropyl)carbodiimide → t-Butyl 3-(Cbz-Val-amido)-5-fluoro-4-liydroxy-pentanoate

Participants

Reaction Steps

To a solution of Cbz-Valine (396 mg, 1.58 mmol) in THF (20 mL) was added 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide (EDCI) (300 mg, 1.57 mmol), 1-hydroxybenzotriazole hydrate (HOBT) (240 mg, 1.57 mmol) and dimethylaminopyridine (DMAP) 129 mg 1.06 mmol). The resulting mixture was stirred for 5 min, then was added a solution of t-butyl 3-amino-5-fluoro-4-hydroxy-pentanoate (215 mg, 1.04 mmol) in THF (10 mL) and it was stirred at rt for 18 h. The mixture was filtered and the THF solution was evaporated, and the residue was purified by chromatography over silica gel ( hexane-EtOAc, 3:2) to give 290 mg (68%) of the titled compound as a white solid. 1HNMR (CDCl3), 0.905 (d, 3H, J=7), 0.965 (d, 3H, J=7), 1.428 (s, 9H), 2.07-2.16 (m, 1H), 2.50-2.57 (m, 1H), 2.64-2.70 (m, 1H), 3.52 (bs, 1H, OH), 3.92-3.96 (m, 2H), 4.20-4.27 (m, 1H), 4.40 (bs, 1H),4.49 (bs, 1H), 5.10 (s, 2H), 5.31-5.4 (m, 1H, NH), 6.86-6.93 (m, 1H, NH), 7.350(s, 5H).

Provenance & Evidence