Iodine → 4-({3,5-Bis[(3,5-di-tert-butylphenyl)vinyl]phenyl}vinyl)toluene

Participants

Reaction Steps

Lithium ethoxide (1.0 M in ethanol, 15.0.mL, 15 mmol) was added to a stirred suspension of 3,5-bis[(3,5-di-tert-butylphenyl)vinyl]benzaldehyde (A) (WO99/9921935) (4.00 g, 7.48 mmol) and 4-methylbenzylphosphoniumchloride (8) (3.62 g, 8.98 mmol) in diethyl ether (40 mL), giving a clear orange solution which was stirred at room temperature for 2 h. The solution was washed with water (3×40 mL) and brine (40 mL), dried over anhydrous magnesium sulphate, filtered and the solvent removed, This residue was passed through a plug of silica with dichloromethane—light petroleum (1:4) as eluent to give a white solid, which was found by 1H NMR to be mainly cis isomer. The solid was heated with iodine (210 mg) and toluene (100 mL) at 100° C. under argon for 6 h and allowed to cool. The solution was washed with saturated aqueous sodium metabisulphite (50 mL) and brine (50 mL) and the solvent removed. The residue was recrystallised from a dichloromethane—hexanes mixture to leave 4-({3,5-bis[(3,5-di-tert-butylphenyl)vinyl]phenyl}vinyl)toluene (9) (3.00 g, 64%) as a white solid. δH(400 MHz, CDCl3) 1.40 (36 H, s, t-butyl), 2.39 (3 H, s, CH3), 7.13 and 7.22 (2 H, d, J 16, core vinyl H), 7.17 and 7.28 (4 H, d, J 16, branch vinyl H), 7.21 and 7.48 (4 H, AA′BB′, core phenyl H), 7.39 (2 H, dd, J 1.5, sp H), 7.43 (4 H, d, J 1.5, sp H), 7.59 (2 H, d, J 1, bp H) and 7.62 (1 H s, bp H).

Provenance & Evidence