反应详情

5-bromopyridin-3-amine (20 g, 116 mmol) was dissolved in DCM (500 mL) and pyridine (28.0 mL, 347 mmol) was added, followed by ethyl chloroformate (11.44 mL, 119 mmol) dropwise. The reaction mixture was stirred for 1.5 h at room temperature. The reaction mixture was diluted with DCM. The two phases were separated and the organic phase was washed with 10% CuSO4 solution (2×) sat. NaHCO3 solution (1×) Brine (1×) dried (Na2SO4) and evaporated. The residue was triturated with diethyl ether filtered and dried obtaining ethyl (5-bromopyridin-3-yl)carbamate (21.58 g, 76%) as a white solid. LCMS (m/z): 247.0 (MH+), 0.58 min; 1H NMR (400 MHz, CDCl3) δ ppm 8.62-8.15 (m, 3H) 7.00 (br. s., 1H) 4.27 (q, J=7.0 Hz, 2H) 1.34 (t, J=7.0 Hz, 3H).

1. customThe two phases were separated
2. washthe organic phase was washed with 10% CuSO4 solution (2×) sat. NaHCO3 solution (1×) Brine (1×)
3. dry with materialdried (Na2SO4)
4. customevaporated
5. customThe residue was triturated with diethyl ether
6. filtrationfiltered
7. customdried