Dichloromethane → 3-Acetoxy-2-(ethoxycarbonyl)methoxypyridine

9.18 g of trifluoromethanesulfonic acid was added to a mixture of 12 g of 3-amino-2-(ethoxycarbonyl)methoxypyridine, 36 ml of 1,2-dimethoxyethane and 12 ml of dichloromethane dropwise at −5° C. The mixture was stirred for 10 minutes at the same temperature, then, to the reaction solution was added a solution of 7.57 g of t-butyl nitrite in 3 ml of 1,2-dimethoxyethane dropwise at −5° C. or lower. The mixture was stirred for 30 minutes at the same temperature, then, into the mixture was poured n-pentane. The lower layer of two separated layers was dissolved in 12 ml of acetic anhydride, and the mixture was stirred for 2.5 hours at 50° C. The reaction solution was poured into ice water, and extracted with t-butyl methyl ether. The organic layer was washed with saturated aqueous sodium bicarbonate solution, then, saturated saline, dried over anhydrous magnesium sulfate, and concentrated. The resulted residue was subjected to silica gel chromatography to obtain 4.2 g of 3-acetoxy-2-(ethoxycarbonyl)methoxypyridine.

1. stirringThe mixture was stirred for 30 minutes at the same temperature
2. stirringthe mixture was stirred for 2.5 hours at 50° C
3. extractionextracted with t-butyl methyl ether
4. washThe organic layer was washed with saturated aqueous sodium bicarbonate solution
5. dry with materialsaturated saline, dried over anhydrous magnesium sulfate
6. concentrationconcentrated

ORD record

ord-cc165c185c494827ad52595c24679763

Source dataset

uspto-grants-2003_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06537948B1