反应详情

To a solution of 5.0 g of ethyl α-bromo-o-toluate, 4.7 g of 9-hydroxy-4-oxo-4H-pyrido[1,2-α]pyrimidine-3-carboxylic acid, ethyl ester, and 200 ml of ethyl methyl ketone is added 3.9 g of anhydrous dipotassium hydrogen phosphate and the mixture stired and heated under reflux for 18 hours. The cooled mixture is filtered, and the filtrate is concentrated in vacuo to give a semi-solid product. To this product, 3.9 g, in 10 ml of acetic acid is added a solution of 0.81 g of hydrogen bromide in 4 ml of glacial acetic acid, dropwise, with agitation. The crystalline product that separates is filtered, washed with anhydrous ether, and recrystallized from acetonitrile to give the named product.

1. temperatureheated
2. temperatureunder reflux for 18 hours
3. filtrationThe cooled mixture is filtered
4. concentrationthe filtrate is concentrated in vacuo
5. customto give a semi-solid product
6. filtrationThe crystalline product that separates is filtered
7. washwashed with anhydrous ether
8. customrecrystallized from acetonitrile
9. customto give the named product