反应详情

温度

90 °C

To a solution of 6-chloro-2,4-dimethyl-nicotinic acid ethyl ester (0.30 g, 1.40 mmol) and 5-pyrimidine boronic acid (0.522 g, 4.21 mmol) in argon-degassed DME/2 M Na2CO3 (4:1, 12.5 ml) was added Pd(PPh3)4 (162 mg, 0.14 mmol) and the mixture heated to 90° C. overnight. The reaction was cooled, diluted with EtOAc (25 ml) and H2O (15 ml). The aqueous layer was extracted with EtOAc (2×10 ml) and the combined organic extracts were dried (Na2SO4), concentrated and purified by column chromatography on silica gel (Hexanes/EtOAc, 3:2) to afford 2,4-dimethyl-6-pyrimidin-5-yl-nicotinic acid ethyl ester (306 mg, 85%). 1H NMR (CDCl3) δ 1.43 (t, 3H, J=6 Hz), 2.44 (s, 3H), 2.64 (s, 3H), 4.47 (q, 2H, J=6 Hz), 7.44 (s, 1H), 9.26 (s, 1H), 9.32 (s, 2H).

1. temperatureThe reaction was cooled
2. extractionThe aqueous layer was extracted with EtOAc (2×10 ml)
3. dry with materialthe combined organic extracts were dried (Na2SO4)
4. concentrationconcentrated
5. custompurified by column chromatography on silica gel (Hexanes/EtOAc, 3:2)