反应详情

Dissolve 2-(2,5-dimethoxy-phenyl)-cyclopent-1-enecarboxylic acid ethyl ester (5 g, 18 mmol) in methanol (150 ml) exchange with N2 3×, add platinum oxide (1.6 g 7.2 mmol), add 60 psi of H2 for 24 hours at room temperature. Filter off catalyst, concentrate the filtrate to give the title compound (4.5 g, 89%): 1H NMR (CDCl3) δ 6.77-6.67 (m, 3H), 3.81 (s, 3H), 3.74 (s, 3H), 3.71-3.57 (m, 3H), 3.32-3.27 (m, 1H), 2.13-1.96 (m, 4H), 1.89-1.83 (m, 1H), 1.70-1.62 (m, 1H), 0.83-0.79 (t, 3H).

1. additionadd 60 psi of H2 for 24 hours at room temperature
2. filtrationFilter off catalyst
3. concentrationconcentrate the filtrate