反応 #554572

反応方程式

NaOH

15a

Methyl 6-trityloxy-hexanoate

NaOH

→

white powder 16a

収率 78.1%

6-Trityloxyhexanoic acid

収率 78.1%

溶媒

THF

water

反応条件

後処理

1. 1
   workup.STIRRINGstirring
2. 2
   workup.WAITwas continued for another 2 days
3. 3
   その他The THF was removed under reduced pressure
4. 4
   抽出extracted with diethyl ether
5. 5
   洗浄The combined organic layers were washed with brine
6. 6
   乾燥dried over MgSO4
7. 7
   その他The diethyl ether was removed under reduced pressure
8. 8
   その他the resulting crude powder was recrystalized in hexanes

実験手順

An aqueous solution of 5 M NaOH (17.5 mL, 87.5 mmol) was added to a stirring solution of 15a (20.1 g, 51.6 mmol) in 130 mL of THF and 52.5 mL of water at room temperature. After stirring for 2 days, 3.1 mL of 5 M NaOH (15.5 mmol) was added, and stirring was continued for another 2 days. The THF was removed under reduced pressure, then the aqueous residue was acidified with 1 M HCl to pH 5 and extracted with diethyl ether. The combined organic layers were washed with brine and dried over MgSO4. The diethyl ether was removed under reduced pressure, and the resulting crude powder was recrystalized in hexanes to yield 15.1 g (78%) of white powder 16a. Mp 114-116° C. 1H-NMR (400 MHz, CDCl3, δH ppm): 7.43 (6H, m, p-Ar), 7.28 (6H, m, m-Ar), 7.22 (3H, m, o-Ar), 3.05 (2H, t, 3JH—H=6.4 Hz, HO—CH2), 2.33 (2H, t, 3JH—H=7.5 Hz, CH2CO2), 1.56-1.68 (4H, m, 2CH2), 1.36-1.47 (2H, m, CH2). 13C-NMR (100 MHz, CDCl3, δH ppm): 180.26, 144.36, 128.62, 127.66, 126.79, 86.30, 63.24, 33.98, 29.63, 25.74, 24.48. HRMS (EI): m/z calcd 374.1882 (C25H26O3), found 374.1883 [M]+.

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