反应详情

2M aqueous Na2CO3 (4.7 ml, 9.4 mmol) was added to a solution of 2,4,5-trichloropyrimidine [Chesterfield, J.; McOmie, J. F. W.; Sayer, E. R.; J. Chem. Soc. (1955) 3478-3481] (1.18 g, 6.44 mmol), tert-butyl N-{1-[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]1-methylethyl}carbamate (1.55 g, 4.29 mmol) and tetrakis(triphenylphosphine)palladium (O) (150 mg, 0.13 mmol) in ethyleneglycol dimethylether (20 ml) under N2 and the mixture heated to reflux for 6 h. The reaction was diluted with H2O (30 ml) and extracted with ethyl acetate (3×50 ml), the combined ethyl acetate extracts were washed with brine (30 ml), dried (MgSO4) and concentrated in vacuo. The crude product was purified by column chromatography (SiO2, 15% ethyl acetate in hexane) to give 4-[4-(1-tert-butoxycarbonylamino-1-methylethyl)phenyl]-2,5-dichloropyrimidine as a white solid (1.34 g). δH (d6DMSO) 8.62 (1H, s), 7.90 (2H, d, J 8.6 Hz), 7.54 (2H, dt, J 8.7, 2.1 Hz), 5.02 (1H, bs), 1.65 (6H, s) and 1.37 (9H, s).

1. temperaturethe mixture heated
2. temperatureto reflux for 6 h
3. extractionextracted with ethyl acetate (3×50 ml)
4. washthe combined ethyl acetate extracts were washed with brine (30 ml)
5. dry with materialdried (MgSO4)
6. concentrationconcentrated in vacuo
7. customThe crude product was purified by column chromatography (SiO2, 15% ethyl acetate in hexane)