反应详情

To a suspension of 5-ethoxycarbonyl-2-methylpyrimid-4-one (2.7 g, 14.75 mmol.) in DME (20 ml), tetrabutylammonium fluoride (22 ml, 22.0 mmol.) was added. The solution was stirred at room temperature until solids dissolved, then 1-bromopinacolone (2.2 ml, 1.1 eq., 16.22 mmol) was added. The solution was stirred overnight and concentrated to a brown oil. The crude mixture was purified by silica gel column chromatography (hexane/ethyl acetate, 100/0 to 0/100). A less polar O-alkylated by-product was eluted first (1.8 g) and then the desired N-alkylated product (1.1 g); MS (281, M+H)+. NMR (CDCl3, δ): 8.57 (1H, s) , 5.06(1H, s), 4.35(2H, q), 2.42 (3H, s), 1.34 (3H, t), 1.30 (9H,s).

1. additionwas added
2. dissolutiondissolved
3. stirringThe solution was stirred overnight
4. concentrationconcentrated to a brown oil
5. customThe crude mixture was purified by silica gel column chromatography (hexane/ethyl acetate, 100/0 to 0/100)
6. washby-product was eluted first (1.8 g)