反应详情

A solution in THF of O-[2-[(2,6-dichloro-3-methylphenyl)amino]phenylmethyl]hydroxylamine (0.50 g, 1.71 mmol), prepared as in step 3, and glyoxylic acid (0.18 g, 1.99 mmol) in THF was stirred for 16 hours. The solution was then diluted with aqueous citric acid and extracted with ethyl acetate (100 mL). The extract was washed with brine, dried over MgSO4, filtered, and concentrated in vacuo to yield an off white solid which was purified by chromatography on silica gel (10% methanol-chloroform). The resulting residue was crystallized from EtOAc/hexanes to provide glyoxylic acid-O-[2-[(2,6-dichloro-3-methylphenyl)amino]phenylmethyl] oxime (0.21 g, 33%) as a white solid. mp 185°-187° C. 1H NMR (300 MHz, DMSO-d6) δ2.38 (s, 3 H), 5.17 (s, 2 H), 6.19 (d, J=7.5 Hz, 1 H), 6.82 (t, J=7.5 Hz, 1 H), 6.97 (s, 1 H), 7.09 (t, J=7.5 Hz, 1 H), 7.25 (m, 2 H), 7.44 (m, 2 H). MS (DCI/NH3) m/z 353 (M+H)+. Anal. Calcd for C16H14N2O3Cl2 ×1.0 H2O: C, 51.76; H, 4.34; N, 7.54. Found: C, 51.78; H, 3.69; N, 7.15.

1. extractionextracted with ethyl acetate (100 mL)
2. washThe extract was washed with brine
3. dry with materialdried over MgSO4
4. filtrationfiltered
5. concentrationconcentrated in vacuo
6. customto yield an off white solid which
7. customwas purified by chromatography on silica gel (10% methanol-chloroform)
8. customThe resulting residue was crystallized from EtOAc/hexanes