反应详情

A solution of tert-butyl 4-(aminocarbonyl)tetrahydro-2H-pyran-4-yl-carbamate (C-25) and triethylamine (2.1 eq.) in dichloromethane was cooled to 0° C. and trifluoroacetic anhydride (1.1 eq.) was added dropwise under nitrogen. Stirring was continued for 1 hour allowing the mixture to reach room temperature. Volatiles were removed in vacuo and residue was taken up in ethyl acetate, washed with HCl 1N, brine and dried over Na2SO4. Evaporation gave a crude which was purified by flash chromatography on silica gel (eluent: petroleum ether: ethyl acetate=7:3) to give the title compound (C-26), colorless oil, as a 8:2 mixture of two rotamers by 1H NMR.

1. customto reach room temperature
2. customVolatiles were removed in vacuo and residue
3. washwashed with HCl 1N, brine
4. dry with materialdried over Na2SO4
5. customEvaporation
6. customgave a crude which
7. customwas purified by flash chromatography on silica gel (eluent: petroleum ether: ethyl acetate=7:3)