Hydrochloric Acid → ethyl(4E)-3-hydroxy-3,5-diphenylpent-4-enoate

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Reaction Steps

Under nitrogen atmosphere, 15 mL of THF was added to 3.05 g (5 mmol, 1.0 equivalent) of (BrZnCH2COOEt.THF)2. Under argon atmosphere, a solution of 1.04 g (5 mmol) of (E)-chalcone in 2.5 mL of THF was added dropwise while stirring at 0˜5° C. The mixture was stirred at 0˜5° C. for 3 hours. 7.5 mL of 1N hydrochloric acid was added dropwise at 20° C. or lower, followed by dilution with 25 mL of ethyl acetate. Then, the layers were separated. The organic layer was washed successively with 5 mL (×2) of 1N hydrochloric acid, 5 mL of an aqueous saturated sodium chloride solution, 10 mL (×2) of an aqueous saturated sodium bicarbonate solution, and 5 mL (×2) of an aqueous saturated sodium chloride solution. After washing, the organic layer was dried with anhydrous magnesium sulfate. Concentration under reduced pressure afforded 1.44 g of the desired product (yield 97%). 1H NMR (CDCl3), (ppm): δ 1.17 (3H, t, J=7.1 Hz), 3.04 (2H, dd, J=22.8, 15.7 Hz), 4.11 (2H, q, J=7.1 Hz), 4.81 (1H, s), 6.42 (1H, d, J=16.0 Hz), 6.66 (1H, d J=16.0 Hz), 7.25-7.53 (10H, m).

Provenance & Evidence