反应详情

338 g of a 30% solution of sodium methylate in methanol are added over 10 minutes to a suspension of 112 g of p-methoxybenzamidine hydrochloride and 101 g of diethyl malonate in 520 ml of ethanol, and the mixture is subsequently refluxed for 5 hours. The reaction mixture is then concentrated by rotary evaporation and the residue is dissolved in 1000 ml of warm water of 80° C. The solution is filtered and the filtrate is acidified to pH 1. The precipitate is isolated by filtration and vacuum dried at 80° C., affording 109.8 g of 2-p-methoxyphenyl-4,6-dihydroxypyrimidine with a melting point of 318° C. (decompos.).

1. temperaturethe mixture is subsequently refluxed for 5 hours
2. concentrationThe reaction mixture is then concentrated by rotary evaporation
3. dissolutionthe residue is dissolved in 1000 ml of warm water of 80° C
4. filtrationThe solution is filtered
5. customThe precipitate is isolated by filtration and vacuum
6. customdried at 80° C.