反応 #979824

反応方程式

15-chloro-3-(1-methylethyl)-6,10,14-tri-methyl-2-trimethylsiloxy-3,5,9,13-pentadecatetraenenitrile

lithium bis(trimethylsilyl) amide

→

2-(1-methylethyl)-5,9,13-trimethyl-1-trimethylsiloxy-2,4,8,12-cyclotetradecatetraene-1-carbonitrile

収率 83.0%

2-(1-methylethyl)-5,9,13-trimethyl-2,4,8,12-cyclotetradeca-tetraen-1-on

収率 16.0%

溶媒

tetrahydrofuran

tetrahydrofuran

反応条件

後処理

1. 1
   その他the reaction is quenched
2. 2
   workup.ADDITIONby adding a saturated aqueous ammonium chloride solution
3. 3
   workup.STIRRINGwhile stirring on an ice-water bath
4. 4
   その他After removing tetrahydrofuran
5. 5
   workup.DISTILLATIONby distillation under reduced pressure
6. 6
   抽出the organic layer is extracted with ether
7. 7
   抽出The obtained extract
8. 8
   その他is purified by silica gel column chromatography (n-hexane/ethyl acetate =60:1)

実験手順

A solution of lithium bis(trimethylsilyl) amide (5.0 mmol, 0.25 M) in dry tetrahydrofuran (20 ml) is stirred under argon atmosphere on an oil bath at 40° C. and thereto is dropwise added a solution of the cyanohydrin trimethylsilyl ether which is 15-chloro-3-(1-methylethyl)-6,10,14-tri-methyl-2-trimethylsiloxy-3,5,9,13-pentadecatetraenenitrile (378 mg, 0.895 mmol) prepared in Reference Example 5 in dry tetrahydrofuran (15 ml) over 50 minutes. After stirring the mixture at this temperature for 20 minutes, the reaction is quenched by adding a saturated aqueous ammonium chloride solution while stirring on an ice-water bath. After removing tetrahydrofuran by distillation under reduced pressure, the organic layer is extracted with ether. The obtained extract is purified by silica gel column chromatography (n-hexane/ethyl acetate =60:1) to give 2-(1-methylethyl)-5,9,13-trimethyl-1-trimethylsiloxy-2,4,8,12-cyclotetradecatetraene-1-carbonitrile (288 mg, 83%) and 2-(1-methylethyl)-5,9,13-trimethyl-2,4,8,12-cyclotetradeca-tetraen-1-on (42.9 mg, 16%).

出典