Sodium hydride → 4-{2-[1-(4-Tert-butyl-phenyl)-ethylideneaminooxy]-ethoxy}-2-hydroxy-benzoic acid methyl ester

Participants

Reaction Steps

To a slurry of sodium hydride (95%) (0.487 g, 20.3 mmol) in tetrahydrofuran (6 mL) was added 1-(4-tert-butyl-phenyl)-ethanone oxime (0.7021 g, 3.67 mmol) as a solution in tetrahydrofuran (18 mL) and the solution was allowed to stir at room temperature for 40 minutes. 4-(2-Bromo-ethoxy)-2-hydroxy-benzoic acid methyl ester (0.908 g, 3.64 mmol) was added as a solution in tetrahydrofuran (10 mL). The reaction was stirred at room temperature 1 hour and then heated at reflux 3 days. The reaction was cooled, quenched with brine and extracted with ethyl acetate. The combined organics were washed with brine, dried over anhydrous magnesium sulfate and concentrated in vacuo. The residue was purified by flash chromatography using ethyl acetate/hexanes (5/95 to 10/90) afford 4-{2-[1-(4-tert-butyl-phenyl)-ethylideneaminooxy]-ethoxy}-2-hydroxy-benzoic acid methyl ester (0.546 g, 39%) as a yellow oil which solidified on standing. mp=65.4-66.8° C.; mass spectrum (+ESI, M+H) m/z 386. 1H NMR (400 MHz, DMSO-d6); δ 10.63 (s, 1H), 7.69 (d, 1H), 7.57 (d, 2H), 7.40 (d, 2H), 6.55 (m, 2H), 4.42 (t, 2H), 4.31 (t, 2H), 3.75 (s, 3H), 2.14 (s, 3H), 1.28 (s, 9H). Elemental analysis: Calcd. for C22H27NO5: C, 68.55; H, 7.06; N, 3.63, Found: C, 68.91; H, 7.10; N, 3.60.

Provenance & Evidence