反应详情

温度

115 °C

A solution of 5-bromo-2-chloropyrimidine (4.03 g, 20.8 mmol), ethyl acrylate (9.06 mL, 83.3 mmol), palladium(II) acetate (187 mg, 0.830 mmol), and tri(o-tolyl)phosphine (762 mg, 2.50 mmol) in DMF (22 mL) and diisopropylethylamine (11 mL) was heated at reflux (115° C. oil bath) for 3.5 h, cooled to room temperature, and diluted with brine. The suspension was extracted with EtOAc (300 mL). The extract was washed (brine) and dried. After solvent removal at reduced pressure, the residue was purified on silica gel (11% EtOAc/hexane) to give 3.26 g (73%) of ethyl(E)-3-(2-chloro-5-pyrimidinyl)-2-propenoate as a yellow solid, mp 125°-127° C. IR 2905, 1698, 1542, 1405, 1160 cm−1; 1H NMR (CDCl3) δ 1.38 (t, J=7.2 Hz, 3H, OCH2CH3), 4.32 (q, J=7.2 Hz, 2H, OCH2CH3), 6.60 (d, J=16.2 Hz, 1H, CH═CHCO), 7.61 (d, J=16.2 Hz, 1H, CH═CHCO), 8.79 (s, 2H, 4-ArH, 6-ArH). HRMS calcd C9H9ClN2O2 [M+H]+ 213.0425. found 213.0428.

1. temperaturecooled to room temperature
2. extractionThe suspension was extracted with EtOAc (300 mL)
3. washThe extract was washed (brine)
4. customdried
5. customAfter solvent removal at reduced pressure
6. customthe residue was purified on silica gel (11% EtOAc/hexane)