Sodium Carbonate → 4-[4-(1-Tert-butoxycarbonylamino-1-methylethyl)phenyl]-2,5-dichloropyrimidine

Beteiligte Stoffe

Reaktionsschritte

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).

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