2-(methoxyimino)acetic acid synthesis

Yield:88012-58-2 99%

Reaction Conditions:

with pyridine in methanol at 20; for 1 h;

Steps:

3

Benzyl (2-methoxyimino)acetate (3) was prepared as follows: methoxylamine hydrochloride salt (75.0 g, 0.90 mol) was added to a stirred solution of glyoxylic acid monohydrate (75.1 g, 0.82 mol) in pyridine/MeOH (1 :1, 1.4 L) under argon. The reaction mixture was stirred at room temperature for one hour and quenched with saturated aqueous NH₄Cl. The aqueous layer was extracted with EtOAc (3x, 700 mL), the organic layers were combined and dried over Na₂SO₄ and concentrated. Purification of the crude material by flash chromatography (8:1 EtOAc/MeOH) furnished methoxyimino-acetic acid as a colorless solid in 83.3 g, 99% yield. R_f = 0.57 (50% CHCl₃MeOH); ¹H δ (CD₃OD): 7.45 (s, IH), 3.98 (s, 3H); ¹³C δ (CD₃OD): 163.8, 141.1, 62.5; Electrospray ionization-MS m/z [M-H]^" calculated for C₃H₄NO₃, 102.0; observed 102.0.

References:

WO2008/67039,2008,A2 Location in patent:Page/Page column 28