反应详情

To a solution of the diethyl 2-(4,5-methylenedioxy-2-methoxybenzyl)-malonate (20.00 g, 0.066 mol) of in ethanol (50 mL) was added a solution of potassium hydroxide (3.50 g, 0.066 mol) in water (25 mL). The solution stirred at reflux for 6 h. After cooling the aqueous layer was washed with ether and acidified with concentrated HCl to pH 1 and extracted with ethyl acetate. The organic extracts were dried (Na2SO4) and concentrated to afford the title compound as a yellow solid (17.30 g, 89%): 1H NMR (400 MHz, CDCl3) δ 10.20 (b, 1H), 6.68 (s, 1H), 6.50 (s, 1H), 5.90 (s, 2H), 4.15 (q, 2H), 3.72 (s, 3H), 3.10 (dd, 2H), 1.20 (t, 3H); MS(ESI) m/e 297.0 [M+H]+.

1. temperatureat reflux for 6 h
2. temperatureAfter cooling the aqueous layer
3. washwas washed with ether
4. extractionextracted with ethyl acetate
5. dry with materialThe organic extracts were dried (Na2SO4)
6. concentrationconcentrated