CC(C)(C)OC(N)=O.COC(=O)c1ncc(Br)cn1>C1COCCO1.CC(=O)O.CC(=O)O.CC1(C)c2cccc(P(c3ccccc3)c3ccccc3)c2Oc2c(P(c3ccccc3)c3ccccc3)cccc21.O=C([O-])[O-].[Cs+].[Cs+].[Pd]>COC(=O)c1ncc(NC(=O)OC(C)(C)C)cn1The methyl 5-bromopyrimidine-2-carboxylate (1 g, 4.61 mmol), tert-butyl carbamate (0.756 g, 6.45 mmol), diacetoxypalladium (0.052 g, 0.23 mmol), (9,9-dimethyl-9H-xanthene-4,5-diyl)bis(diphenylphosphine) (0.267 g, 0.46 mmol), cesium carbonate (2.252 g, 6.91 mmol) and dioxane (15 mL) were placed and sealed into a microwave tube. The reaction was degased, purged with argon and heated to 90 °C (oil bath) over a period of 7 hours . The mixture was poured in water, extracted with ethyl acetate (x2). The organic phase was washed with brine, dried over magnesium sulfate and concentrated. The crude product was purified by flash chromatography on silica gel 15-40µm eluting with 5 to 50% ethyl acetate in petroleum ether. The solvent was evaporated to dryness to afford methyl 5-(tert- butoxycarbonylamino)pyrimidine-2-carboxylate (0.710 g, 60.8 %) as a white solid.
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