反応 #213919

反応方程式

magnesium

propargyl bromide

1,1-dimethoxy-2-hexanone

imidazole

trimethylchlorosilane

1,2-dibromoethane

ammonium chloride

magnesium sulfate

→

title compound

4-Dimethoxymethyl-4-trimethylsiloxy-1-octyne

溶媒

ether

tetrahydrofuran

water

ether

ether

反応条件

後処理

1. 1
   workup.ADDITIONTo a suspension of 5.31 g
2. 2
   workup.ADDITIONfollowed by the dropwise addition of a solution of 25 g
3. 3
   workup.ADDITIONMidway through the addition 15 ml
4. 4
   workup.ADDITIONAfter complete addition of the solution
5. 5
   温度the mixture is refluxed for 40 minutes
6. 6
   ろ過The mixture is filtered through Celite
7. 7
   その他the solvent is removed
8. 8
   workup.DISSOLUTIONThe residue is dissolved in 53 ml
9. 9
   workup.ADDITIONof dimethylformamide and at 0° C. is added 24.4 g
10. 10
    抽出extracted with hexanes
11. 11
    乾燥The organic layer is dried over magnesium sulfate
12. 12
    その他the solvent is removed
13. 13
    workup.DISTILLATIONDistillation (75°-95° C., 0.3 mm.)
14. 14
    その他gives 17.4 g

実験手順

To a suspension of 5.31 g. (0.22 moles) of magnesium in 15 ml. of ether is added 100 mg. of mercuric chloride and 1.5 ml. of 1,2-dibromoethane. After the reaction begins, another 45 ml. of ether is added followed by the dropwise addition of a solution of 25 g. (0.16 moles) of 1,1-dimethoxy-2-hexanone and 27.3 g. (0.2 moles) of 85% propargyl bromide in 45 ml. of ether at a rate which maintains reflux. Midway through the addition 15 ml. of tetrahydrofuran is added. After complete addition of the solution, the mixture is refluxed for 40 minutes. The mixture is cooled to 0° C. and saturated ammonium chloride solution is added followed by magnesium sulfate. The mixture is filtered through Celite and the solvent is removed. The residue is dissolved in 53 ml. of dimethylformamide and at 0° C. is added 24.4 g. (0.36 moles) of imidazole and 21.19 g. (0.20 moles) of trimethylchlorosilane. After stirring at 25° C. for 70 minutes, the solution is poured into water and extracted with hexanes. The organic layer is dried over magnesium sulfate and the solvent is removed. Distillation (75°-95° C., 0.3 mm.) gives 17.4 g. of the title compound.

出典