反应详情

2-Methoxypyrimidine-5-carbaldehyde (see J. Heterocycl. Chem. (1991) 28, 1281) (9.00 kg) was reacted with ethylacetoacetate (17.8 kg) in the presence of piperidine (555 g) in propan-2-ol (90 L) at 50° C. for several hours, followed by a hydrolysis with aqueous sodium hydroxide (24.2 kg of 46% NaOH in 30 L of water) at 0° C. Phase separation of the resulting mixture, acidification of the aqueous layer with concentrated hydrochloric acid (23.2 kg) to pH 2-3 and crystallization afforded the title compound (12.7 kg; 85% yield).

1. customPhase separation of the resulting mixture, acidification of the aqueous layer with concentrated hydrochloric acid (23.2 kg)
2. customto pH 2-3 and crystallization