反应详情

To a solution of the mixture of 4-Oxo-4,5,6,8-tetrahydro-3H-pyrido[3,4-d]pyrimidine-6,7-dicarboxylic acid 7-tert-butyl ester 6-ethyl ester and 4-Oxo-3,5,7,8-tetrahydro-4H-pyrido[4,3-d]pyrimidine-6,7-dicarboxylic acid 6-tert-butyl ester 7-ethyl ester (1.5 g, 4.64 mmol) in DCE (25 mL), carbon tetrachloride (1.34 mL, 13.9 mmol) and triphenylphosphine (2.43 g, 9.28 mmol) are added. The reaction is heated at reflux and after completion of reaction as judged by LCMS. The solvents are removed and the products are isolated using FCC eluting with heptane:EtOAc 80:20. At this point the two products are separated. 4-Chloro-5,8-dihydro-6H-pyrido[3,4-d]pyrimidine-6,7-dicarboxylic acid 7-tert-butyl ester 6-ethyl ester MS (ESI) m/z 342.1 (M+1) and 4-chloro-7,8-dihydro-5H-pyrido[4,3-a]pyrimidine-6,7-dicarboxylic acid 6-tert-butyl ester 7-ethyl ester MS (ESI) m/z 342.1 (M+1) are isolated as an almost 4:1 ratio.

1. additionare added
2. temperatureThe reaction is heated
3. temperatureat reflux
4. customafter completion of reaction
5. customThe solvents are removed
6. customthe products are isolated
7. washeluting with heptane:EtOAc 80:20
8. customAt this point the two products are separated