反应详情

To a solution of 4-(2-tert-butoxycarbonyl-vinyl)-3-ethyl-5-methyl-benzoic acid benzyl ester (10.0 g, 26 mmol) in THF 100 mL), Pd/C (0.5 g, 20% Pd) is added under nitrogen. The mixture is stirred at rt for 48 h under 1 bar of H2. The catalyst is filtered off over a celite pad and the filtrate is concentrated to dryness to give 4-(2-tert-butoxycarbonyl-ethyl)-3-ethyl-5-methyl-benzoic acid (7.64 g) as a white solid; 1H NMR δ 1.29 (t, J=7.5 Hz, 3 H), 1.49 (s, 9 H), 2.36-2.41 (m, 2 H), 2.74 (q, J=7.5 Hz, 2 H), 2.99-3.05 (m, 2 H), 7.77 (s, 1 H), 7.80 (s, 1 H).

1. filtrationThe catalyst is filtered off over a celite pad
2. concentrationthe filtrate is concentrated to dryness