反应详情

A solution of aqueous hydroxylamine (50% w/w, 65.6 cm3, in N,N-dimethylformamide (250 cm3) was cooled over a NaCl—ice bath. Ethyl acetate (46.5 cm3, 0.475 mol) was added and the solution stirred below 0° C. A 25 cm3 portion of this solution was added to a suspension of 3,5-bis[3,5-bis(3,5-di-tert-butylphenyl-E-vinyl)phenyl-E-vinyl]benzyl alcohol (2.09 g, 1.78 mmol) in toluene (42 cm3) and the mixture heated to 100° C. A homogeneous solution had formed after a few minutes. The remaining hydroxylamine solution was added portionwise over 3 h with stirring maintained at 100° C., and continued at 100° C. for a further 2 h after the addition was complete. The solution was allowed to cool overnight. Water (150 cm3) was added and the mixture extracted with ether (2×150 cm3). The combined extracts were washed with aqueous hydrochloric acid (3 M, 150 cm3), water (150 cm3) and brine (150 cm3), dried over anhydrous magnesium sulphate, filtered and the solvent removed. Analysis of the residue by 1H NMR indicated incomplete reduction of the vinyl bonds had occurred. The residue was therefore subjected to the same reaction conditions as above but without the toluene, in the place of the alcohol, to give, upon solvent removal, 3,5-bis(2-{3,5-bis[2-(3,5-di-tert-butylphenyl)ethyl]phenyl}ethyl)benzyl alcohol as a white solid foam (2.105 g, 100%), (Found: C, 88.0; H, 10.3. C87H120O requires C, 88.4; H, 10.2%); νmax(KBr)/cm−1 1600 (C═C); λmax(CH2Cl2)/nm 265 (log(ε/dm3 mol−1 cm−1) 3.38), 269 sh (3.36), 306 (3.08), 317 (3.08), and 332 sh (2.87); δH(400 MHz, CDCl3) 1.35 (72 H, s, t-butyl), 1.61 (1 H, t, J 6 CH2OH), 2.91 (24 H, s, CH2CH2), 4.70 (2 H, d, J6, CH2OH), 6.97 (6 H, s, G1 bp-H), 7.09 (9 H, m, sp-H and cp-H), 7.12 (2 H, s, cp-H) and 7.30 (4 H, dd, J2, sp-H); m/z (MALDI) 1204.9 (MNa+, 100%). A solution of 3,5-bis(2-{3,5-bis[2-(3,5-di-tert-butylphenyl)ethyl]phenyl}ethyl)benzyl alcohol (1.317 g, 1.114 mmol) and pyridinium chlorochromate (0.480 g, 2.23 mmol) in dichloromethane (20 cm3) was heated to reflux for 1 h and allowed to cool overnight. The dark brown slurry was then filtered through a plug of silica with dichloromethane as eluent to give 16 (1.29 g, 98%) as a white solid foam, (Found: C, 88.3; H, 10.1. C87H118O requires C, 88.6; H, 10.1%); νmax(KBr)/cm−1 1701 (C═O) and 1600 (C═C); λmax(CH2Cl2)/nm 257 (log(ε/dm3 mol−1 cm−1) 4.12) and 300 (3.43); δH(400 MHz, CDCl3) 1.35 (72 H, s, t-butyl), 2.90-2.99 (24 H, m, CH2CH2), 6.94 (4 H, d, J1, bp-H), 6.97 (2 H, s, bp-H), 7.08 (8 H, d, J2, sp-H), 7.30 (4 H, dd, J2, sp-H), 7.36 (1 H, s, cp-H), 7.61 (2 H, d, J1.5, cp-H) and 10.01 (1 H, s, CHO); m/z (MALDI) 1202.2 (MNa+, 100%).

1. temperatureto reflux for 1 h
2. temperatureto cool overnight
3. filtrationThe dark brown slurry was then filtered through a plug of silica with dichloromethane as eluent