Ethanol → (6-Methoxy-indan-1-ylidene)-acetic acid ethyl ester

Participants

Reaction Conditions

Reaction Steps

6-Methoxy-indan-1-one (5.02 g, 30.95 mmol) and triethyl phosphonoacetate (15.5 mL, 78.13 mmol) was dissolved in THF (20 mL) and added slowly to a mixture of EtOH (850 μL) and NaH (60% dispersion in oil, 2.5 g). The resulting slurry was stirred at 70° C. overnight. The crude mixture was diluted with diethyl ether and washed with water and brine, dried (Na2SO4), filtered and concentrated. The product was purified by silica gel flash column chromatography (5:1 hexanes in ethyl acetate) to afford (6-Methoxy-indan-1-ylidene)-acetic acid ethyl ester (3.18 g, 47%) as a mixture (˜1:1) of E/Z isomers. 1H NMR (400 MHz, CDCl3) mixture (˜1:1) of E/Z isomers δ 7.37 (d, 1H) 7.27 (d, 1H), 7.09 (d, 1H), 6.99 (dd, 1H), 6.97 (d, 1H), 6.81 (dd, 1H), 6.50 (m, 1H), 6.31-6.30 (m, 1H), 4.27 (quart, 2H), 4.22 (quart, 2H), 3.87 (s, 3H), 3.86 (s, 3H), 3.60 (m, 2H), 3.36-3.33 (m, 4H), 3.05-3.02 (m, 2H), 1.37 (t, 3H), 1.31 (t, 3H).

Provenance & Evidence