反应详情

To a solution of (3-(hydroxyimino-methyl)-phenoxy)-acetic acid tert-butyl ester prepared of Preparation 20, Step B (2.25 g, 5.96 mmol) in EtOH (10 mL) was added Raney Nickel (about 1 g, washed with water followed by EtOH) in 100 mL EtOH. Additional EtOH (90 mL) was required for the transfer. Ammonium hydroxide (10 mL) was added and the mixture was shaken under 45 psi for H2 for 4 hours. The catalyst was removed via filtration through Celite® and the solution was concentrated to a clear oil. Purification via flash chromatography on silica gel (96.5/3.5/0.1 to 9/1/0.1 CH2Cl2/MeOH/NH4OH) afforded the title compound as a yellow oil. 1H NMR (400 MHz, CDCl3) δ 7.23 (m, 1H), 6.92 (m, 2H), 6.72 (d, 1H), 4.50 (s, 2H), 3.82 (s, 2H), 1.96 (m, 2H), 1.46 (s, 9H); MS 238 (M+1).

1. customThe catalyst was removed via filtration through Celite®
2. concentrationthe solution was concentrated to a clear oil
3. customPurification via flash chromatography on silica gel (96.5/3.5/0.1 to 9/1/0.1 CH2Cl2/MeOH/NH4OH)