反应详情

A solution of 3-[4-hydroxy-2-(hydroxyimino-methyl)-phenyl]-acrylic acid tert-butyl ester (0.50 g, 1.9 mmol) in ethanol (50 mL) was treated with 10% palladium on carbon (0.25 g). The resulting suspension was treated with hydrogen using a Parr shaker apparatus at ambient temperature and 50 psi for 16 h. The reaction mixture was filtered through Celite, rinsed with ethanol (20 mL), and concentrated. The residue was dissolved in ethyl acetate (50 mL) and washed with 10% K2CO3 solution (2×25 mL) and 1N NaOH (2×25 mL). The organic layer was dried (Na2SO4), filtered, and concentrated. The residue was crystallized from isopropyl acetate to give the title compound (0.14 g, 40%), mp 154-157° C. 1H NMR (CD3OD): δ 1.37 (s, 9H), 2.44-2.50 (t, 2H), 2.80-2.85 (t, 2H), 3.75 (s, 2H), 4.83 (s, 3H), 6.57-6.63 (dd, 1H), 6.75-6.77 (d, 1H), 6.95-7.00 (d, 1H). MS (ES+) m/z 252.1 ([M+H]+). MS (ES−) m/z 250.2 ([M−H]−). Anal. Calculated for C14H21NO3: C: 66.9069; H: 8.4222; N: 5.5731. Found: C: 66.57; H: 8.29; N: 5.60.

1. filtrationThe reaction mixture was filtered through Celite
2. washrinsed with ethanol (20 mL)
3. concentrationconcentrated
4. dissolutionThe residue was dissolved in ethyl acetate (50 mL)
5. washwashed with 10% K2CO3 solution (2×25 mL) and 1N NaOH (2×25 mL)
6. dry with materialThe organic layer was dried (Na2SO4)
7. filtrationfiltered
8. concentrationconcentrated
9. customThe residue was crystallized from isopropyl acetate