反応 #1869152

反応方程式

ethyl 3-oxododecanoate

ethylene glycol

p-TsOH

→

ethyl 3,3-ethylenedioxydodecanoate

収率 79.0%

溶媒

benzene

反応条件

後処理

1. 1
   その他The solvent was removed
2. 2
   workup.ADDITIONthe residue was diluted with 50 mL ethyl acetate
3. 3
   洗浄The solution was washed with saturated aqueous NaHCO3 (50 mL) and brine (50 mL)
4. 4
   乾燥the organic phase was dried over MgSO4
5. 5
   濃縮concentrated
6. 6
   その他The residue was purified by flash chromatography (hexane/EtOAc 8:1, Rf=0.21)

実験手順

The mixture of ethyl 3-oxododecanoate (1.456 g, ca. 5 mmol), ethylene glycol (2.78 mL, 50 mmol) and a catalytic amount of p-TsOH (95 mg, 0.5 mmol) in benzene (50 mL) was heated to 110° C. under an argon atmosphere overnight. The solvent was removed, and the residue was diluted with 50 mL ethyl acetate. The solution was washed with saturated aqueous NaHCO3 (50 mL) and brine (50 mL), and the organic phase was dried over MgSO4 and concentrated. The residue was purified by flash chromatography (hexane/EtOAc 8:1, Rf=0.21) to give ethyl 3,3-ethylenedioxydodecanoate (1.131 g, 3.95 mmol) in 79% overall yield for the above two steps. 1H NMR (500 MHz, CDCl3) δ 0.88 (t, J=7 Hz, 3H), 1.20-1.44 (m, 17H), 1.76-1.82 (m, 2H), 2.65 (s, 2H), 3.94-4.04 (m, 4H), 4.16 (q, J=7 Hz, 2H); 13C NMR (125 MHz, CDCl3) δ 14.1, 22.6, 23.4, 29.22, 29.43, 29.48, 29.62, 31.8, 37.7, 42.5, 60.4, 65.0, 109.4, 169.5.

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