反应详情

Triethyl amine (73.1 mL, 526.6 mmol) was added slowly to a solution of 5-Bromo-2,4-dichloro-pyrimidine (40 g, 175.5 mmol) in acetonitrile (400 mL) at 00° C. and then 2-Methoxy-1,1-dimethyl-ethylamine (Preparation 255, 23.4 g, 263.3 mmol) was added to the mixture portion wise. The reaction mixture was stirred for another 16 hours at room temperature. TLC showed the presence of unreacted starting pyrimidine, but the reaction was not continued further. All the volatiles were removed in vacuo and the residue was taken in ethyl acetate, washed with water, brine, dried over sodium sulphate and evaporated to dryness in vacuo. The crude material was purified by column chromatography on silica gel (100-200 mesh, gradient of ethyl acetate:hexane 1:9 to 2:4) to afford the title compound as white solid in 23% yield (10 g of starting pyrimidine was recovered), 12 g.

1. customAll the volatiles were removed in vacuo
2. washwashed with water, brine
3. dry with materialdried over sodium sulphate
4. customevaporated to dryness in vacuo
5. customThe crude material was purified by column chromatography on silica gel (100-200 mesh, gradient of ethyl acetate:hexane 1:9 to 2:4)