反応 #5353

反応方程式

8-carbomethoxyoctanal

4-chlorobenzyltriphenylphosphonium chloride

water

potassium hexamethyldisilazide

→

10-(4-chlorophenyl)-dec-9-enoic acid methyl ester

収率 13.0%

溶媒

tetrahydrofuran

tetrahydrofuran

反応条件

後処理

1. 1
   workup.ADDITIONis added dropwise
2. 2
   温度to warm to room temperature
3. 3
   workup.STIRRINGstirred for 2 days
4. 4
   抽出extracting three times with diethyl ether
5. 5
   洗浄washed with brine
6. 6
   乾燥dried over Na2SO4
7. 7
   ろ過filtered
8. 8
   濃縮concentrated in vacuo
9. 9
   その他to give a yellow solid
10. 10
    ろ過Pad filtration through flash silica gel eluting with 10% ethyl acetate/hexane
11. 11
    その他gives a yellow oil
12. 12
    濃縮after concentration in vacuo
13. 13
    洗浄Flash chromatography on a 60 mm×150 mm silica column eluting with 5% ethyl acetate/hexane

実験手順

To a solution of 18.2 g (43 mmol) of 4-chlorobenzyltriphenylphosphonium chloride in 200 mL of dry tetrahydrofuran at -78° C. is added dropwise, 30.7 mL (43 mmol) of a 1.4M solution of potassium hexamethyldisilazide in tetrahydrofuran. This is allowed to stir for 1 hour when 8.0 g (43 mmol) of 8-carbomethoxyoctanal is added dropwise. The solution is stirred at -78° C. for 2 hours, allowed to warm to room temperature, and stirred for 2 days. The reaction is worked up by adding water and extracting three times with diethyl ether. The ether extracts are combined, washed with brine, dried over Na2SO4, filtered, and concentrated in vacuo to give a yellow solid. Pad filtration through flash silica gel eluting with 10% ethyl acetate/hexane, gives a yellow oil after concentration in vacuo. Flash chromatography on a 60 mm×150 mm silica column eluting with 5% ethyl acetate/hexane gives 1.62 g (13%) of 10-(4-chlorophenyl)-dec-9-enoic acid methyl ester as a mixture of E and Z isomers.

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