Reaktion #1463481

Reaktionsgleichung

2-(1,3-dioxan-2-yl)ethyltriphenylphosphonium bromide

tetrahydrofuran

tetrahydrofuran

4-(3-fluoro-4-trifluoromethoxyphenyl)cyclohexanone

potassium t-butoxide

→

1-(2-(1,3-dioxan-2-yl)ethylidene)-4-(3-fluoro-4-trifluoromethoxyphenyl)cyclohexane

Lösungsmittel

ether

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeInto a three-necked flask equipped with a dropping funnel
2. 2
   Sonstigereached 10° C
3. 3
   SonstigeThe resulting reaction mixture
4. 4
   Sonstigeup to room temperature
5. 5
   Sonstigefor one hour
6. 6
   workup.STIRRINGstirring for one hour
7. 7
   workup.STIRRINGfurther stirring the reaction mixture for 5 hours
8. 8
   workup.ADDITIONafter completion of the dropwise addition
9. 9
   Filtrationfiltering off
10. 10
    Einengenconcentrating the filtrate under reduced pressure
11. 11
    Sonstigeisolating
12. 12
    Sonstigepurifying the resulting pale brown oil by means of silica gel column chromatography

Vorschrift

Into a three-necked flask equipped with a dropping funnel, a three-way cook and a thermometer was placed 2-(1,3-dioxan-2-yl)ethyltriphenylphosphonium bromide (9.1 g, 20 mmols), followed by adding tetrahydrofuran (100 ml), suspending, stirring under ice cooling till the liquid temperature reached 10° C. The resulting reaction mixture was added potassium t-butoxide (2.2 g, 20 mmols) followed by elevating the temperature up to room temperature under ice cooling for one hour, stirring for one hour, dropwise adding a tetrahydrofuran (50 ml) solution of 4-(3-fluoro-4-trifluoromethoxyphenyl)cyclohexanone (5.5 g, 20 mmols) over 30 minutes from the dropping funnel, further stirring the reaction mixture for 5 hours after completion of the dropwise addition, adding ether (100 ml), allowing to stand for one hour, filtering off deposited insoluble substance, concentrating the filtrate under reduced pressure, and isolating and purifying the resulting pale brown oil by means of silica gel column chromatography, to obtain 1-(2-(1,3-dioxan-2-yl)ethylidene)-4-(3-fluoro-4-trifluoromethoxyphenyl)cyclohexane.

Quelle