Water → HCID 133191, compound

Participants

Reaction Conditions

Reaction Steps

To the crude 1-(3,5-dimethoxy-4-i-propylphenyl)-2-phenylethene (18.07 g) in dry CH2Cl2 (100 mL) at −78° C. under N2 was added BBr3 (5.2 mL, 55 mmol) dropwise. After the reaction was stirred at −78° C. for 1 h, the temperature was allowed to rise to room temperature and the reaction mixture was stirred at room temperature for 2 days. Water was added to quench the reaction, followed by 20% NaOH to adjust pH>12. The organic layer was removed and the aqueous layer was washed with hexane (2×100 mL). The aqueous layer was acidified with 6N HCl to pH 1 and extracted with ether (3×200 mL). The organic layer was separated and washed with water (50 mL) and brine (50 mL) and dried over anhydrous Na2SO4. Evaporation of ether gave a red syrup. Recrystallization with chloroform yielded pure stilbene product 20B (6.92 g) as a white crystal. The mother liquid was concentrated and the residue was recrystallized once more to afford an additional 2.5 g of 20B (total 9.42 g, 67.7% over two steps). 1HNMR (CDCl3, ppm): δ 1.38 (d, J=7.3 Hz, 6H), 3.46 (hept., J=7.3 Hz, 1H), 4.80 (s, 2H), 6.50 (s, 2H), 6.92 (d, J=17.2 Hz, 1H), 6.97 (d, J=17.2 Hz, 1H), 7.25 (m, 1H), 7.34 (m, 2H), 7.52 (m, 2H).

Provenance & Evidence