تفاعل #1797476

معادلة التفاعل

PCC

6-benzyloxy-1-tetradecanol

→

6-benzyloxy-tetradecanal

المذيبات

methylene chloride

ظروف التفاعل

المعالجة

1. 1
   ترشيحfiltered through a bed of silica gel

الإجراء التجريبي

PCC (9.7 g, 45 mmol) was added in portions to a solution containing 6-benzyloxy-1-tetradecanol (7.5 g, 30 mmol) in methylene chloride (100 ml) at RT. The black mixture was stirred for 2 hours, then filtered through a bed of silica gel using hexane:ethyl acetate (90:10). The corresponding aldehyde, 6-benzyloxy-tetradecanal, was produced at a yield of 6.1 g (81%). This aldehyde compound was mixed with carbethoxymethylene triphenylphosphorane (10 g, 29 mmol) in 100 ml of methylene chloride at RT. The mixture was allowed to stir overnight, after which the solvent was removed and replaced with hexane. Solid precipitates were removed by filtration. Following chromatography on silica gel using hexane:ethyl acetate at a ratio of 90:10, the corresponding ester was detected at 8.4 g scale (90%). The chemical shift of the ester, 8-benzyloxyhexadec-2-enoate ethyl ester, is as follows: 1H-NMR (CDCl3) δ 0.89 (m, 6H, CH3), 1.2-1.5 (m, 20H, CH2), 2.2 (m, 2H, CH2—C═), 3.35 (m, 2H, CH2O), 4.2 (q, 2H, MeCH2—O), 4.55 (dd, 2H, CH2—O), 5.8 (d, 1H, CH═C), 6.95 (d,t 1H, CH═C), 7.35 (m, 5H, benzyl).

المصدر