反应详情

2-Amino-7,8-dihydro-5H-pyrido[4,3-d]pyrimidine-6-carboxylic acid tert-butyl ester 528 mg (2.11 mmol) was added at 0° C. to a solution of 2-ethoxybenzoic acid chloride 390 mg (2.11 mmol) in pyridine (25 ml) and stirring was performed for 2 h at 0° C. and then for 72 h at RT under nitrogen as inert gas. After the addition of aqueous 1 M NaOH (40 ml) and stirring for 20 minutes, CH2Cl2 (50 ml) was added and the aqueous phase extracted with CH2Cl2 (3×20 ml). The combined organic phases were dried over Na2SO4. After filtration and removal of the solvent, purification was performed by means of column chromatography and the product 2-(2-ethoxy-benzoylamino)-7,8-dihydro-5H-pyrido[4,3-d]pyrimidine-6-carboxylic acid tert-butyl ester 600 mg (1.51 mmol, 72% of theoretical) was obtained.

1. waitfor 72 h at RT under nitrogen as inert gas
2. stirringstirring for 20 minutes
3. extractionthe aqueous phase extracted with CH2Cl2 (3×20 ml)
4. dry with materialThe combined organic phases were dried over Na2SO4
5. filtrationAfter filtration and removal of the solvent, purification