Acetic Anhydride → N-(4,6-Dichloropyrimidin-2-yl)formamide
反応式
[NH2:1][C:2]1[N:7]=[C:6]([Cl:8])[CH:5]=[C:4]([Cl:9])[N:3]=1.[C:10](OC(=O)C)(=[O:12])C>C(O)=O>[CH:10]([NH:1][C:2]1[N:7]=[C:6]([Cl:8])[CH:5]=[C:4]([Cl:9])[N:3]=1)=[O:12]参加物
4
反応条件
- 温度
- 50 °C
実験手順
A 250 ml. three necked flask was fitted with a mechanical stirrer, a thermometer, and a reflux condenser with drying tube. To the flask was charged 70 ml. of a 98% formic acid and 3.85 g (0.025 mole) of 2-amino-4,6-dichloropyrimidine as prepared in example 1. Acetic anhydride, 30 ml. was added slowly with stirring to maintain temperature below 50° C. When the addition of acetic anhydride was complete, the mixture was heated for 6 more hours at 50° C and then allowed to stand overnight at room temperature. Excess formic acid and acetic anhydride were evaporated under vacuum. The solid residue was crystallized from 15 ml. of ethyl alcohol. There was obtained 3.7 g of 2-formamido-4,6-dichloropyrimidine (PY-24) in the form of white crystals, melting point, 142°-144° C, yield 77%.