115012-09-4

The general procedure for the synthesis of 7-hydroxy-6,7-dihydro-5H-pyrrolo[3,4-b]pyridin-5-one and compounds (CAS:115012-10-7) from 2,3-pyridinedicarboximide was as follows: 0.74 g (5 mmol) of 2,3-pyridinedicarboximide was dissolved in 50 ml of a solvent mixture of methanol and chloroform at -20 °C ( methanol:chloroform=1:1, V/V). Subsequently, 0.283 g of sodium borohydride was added and the reaction was monitored by TLC until the disappearance of the feedstock spot. Upon completion of the reaction, the pH of the reaction solution was first adjusted to 3 with 3 mol/L hydrochloric acid, and then adjusted to pH 9 with 2 mol/L sodium hydroxide solution. the solvent was removed by concentration under reduced pressure, and the resulting mixture was separated by silica gel column chromatography (eluent: dichloromethane:methanol=15:1, V/V) to give a white solid (a mixture of compound a-1 and compound b-1 in the ratio of about 3:1 ). Finally, the two isomers were isolated by ethanol recrystallization in 45.1% yield of compound a-1.

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