反应详情

To a stirred solution of 2-((tert-butoxycarbonyl)amino)-5,5,5-trifluoropentanoic acid (500 mg, 1.843 mmol) in THF (15 mL) cooled to −10° C. under nitrogen atmosphere was added N-methylmorphline (0.223 mL, 2.028 mmol) followed by isobutyl chloroformate (0.266 mL, 2.028 mmol) dropwise. The solution was then stirred for 30 min then filtered. The filtrate was added to sodium borohydride (147 mg, 3.87 mmol) in water (10 mL), stirred for 5 min and diluted with ethyl acetate (10 mL). The organic layer was separated and washed with brine (2×10 mL), dried (Na2SO4) and evaporated under reduced pressure to afford tert-butyl (5,5,5-trifluoro-1-hydroxypentan-2-yl)carbamate (400 mg, 1.555 mmol, 84% yield) as a white solid which was taken to the next step without further purification. 1H NMR (400 MHz, MeOD) δ 3.44-3.56 (m, 3H), 2.16-2.26 (m, 2H), 1.83-1.92 (m, 1H), 1.57-1.67 (m, 1H), 1.47 (s, 9H).

1. filtrationthen filtered
2. stirringstirred for 5 min
3. customThe organic layer was separated
4. washwashed with brine (2×10 mL)
5. dry with materialdried (Na2SO4)
6. customevaporated under reduced pressure