Water → methyl 2-(N-hydroxyimino)-2-(pyridin-2-yl)acetate

Reaction equation

[CH3:1][O:2][C:3](=[O:11])[CH2:4][C:5]1[CH:10]=[CH:9][CH:8]=[CH:7][N:6]=1.[N:12]([O-])=[O:13].[Na+].O>CC(O)=O>[CH3:1][O:2][C:3](=[O:11])[C:4](=[N:12][OH:13])[C:5]1[CH:10]=[CH:9][CH:8]=[CH:7][N:6]=1

Participants

Procedure

To a solution of pyridin-2-yl-acetic acid methyl ester (8.9 ml, 0.66 mmol) in AcOH (16 mL) at 0° C. with stirring, an aqueous solution of sodium nitrite (4.67 g, 0.66 mmol in 14 mL) was added portion wise. After addition was completed stirring was continued for 40 min at room temperature. Water (30 mL) was added and the mixture was stirred for additional 1 h. The mixture was concentrated to remove most of the AcOH and basidified to pH 8˜9 with Na2CO3 aq. extracted with EtOAc (3×). The combined organics were dried over MgSO4, filtered, and concentrated in vacuo. Drying in a vacuum oven affords Hydroxyimino-pyridin-2-yl-acetic acid methyl ester (11.6 g, 97%) as an off-white solid, m/z 181.6 [M+1]+