反应详情

Malonic acid (13.03 g; 126.2 mmol) and redistilled piperidine (2 ml) were added to a solution of 5-formyl-2,4,dimethoxypyrimidine (10.52 g; 6.2.6 mmol) in dry pyridine (60 ml). The mixture was heated on a steam bath for 10 h then the solvent was removed by distillation under reduced pressure. The residual oil was re-evaporated from water (3×25 ml) and the solid thus obtained recrystallised firstly from water and then from dry methanol to give the product as white needles, yield 6.45 g; a second crop was obtained from the filtrate (1.08 g). Total yield 7.53 g (57%). Mass spectrum: (El) m/z 210 (M+). Analysis, found: C,52.1;H,4.8;N, 13.1%: C9H10N2O4 requires: C, 52.43; H, 4.79; N, 13.33%.

1. temperatureThe mixture was heated on a steam bath for 10 h
2. customthe solvent was removed by distillation under reduced pressure
3. customThe residual oil was re-evaporated from water (3×25 ml)
4. customthe solid thus obtained
5. customrecrystallised firstly from water