Reaction #710528

Reaction equation

Compound I

2-(1,3-benzodioxol-5-yl)-2-methyl propanal

t-BuOK

→

desired Compound

5-(2-methylbut-3-en-2-yl)benzo[d][1,3]dioxole

Solvents

tetrahydrofuran

tetrahydrofuran

Conditions

Workup

1. 1
   workup.STIRRINGThe reaction mixture was stirred at 0° C. for 1 hour and at room temperature for 2 hours
2. 2
   Temperaturerefluxed for 5 hours
3. 3
   TemperatureIt was then cooled to 0° C.
4. 4
   Otherquenched by NH4Cl solution
5. 5
   workup.STIRRINGwith stirring for 30 minutes
6. 6
   ExtractionThe reaction mixture was then extracted with diethyl ether
7. 7
   WashThe ether layer was washed with distilled water
8. 8
   Dryingdried over anhydrous sodium sulfate
9. 9
   Filtrationfiltered
10. 10
    Otherevaporated
11. 11
    OtherPurification on silica gel column

Procedure

A suspension of methyl triphenyl phosphonium bromide (325 mg, 0.95 mmol) and t-BuOK (87.5 mg, 0.78 mmol) in dry tetrahydrofuran (1 mL) was stirred at 0° C. for 1 hour. To this mixture at 0° C., a solution of Compound I (50 mg, 0.26 mmol) in dry tetrahydrofuran (1 mL) was added dropwise. The reaction mixture was stirred at 0° C. for 1 hour and at room temperature for 2 hours and then refluxed for 5 hours. It was then cooled to 0° C. and quenched by NH4Cl solution with stirring for 30 minutes. The reaction mixture was then extracted with diethyl ether. The ether layer was washed with distilled water, dried over anhydrous sodium sulfate, filtered and evaporated. Purification on silica gel column using petroleum ether followed by with 20:1 petroleum ether-ethyl acetate afforded desired Compound No. 14 (1 mg) as colourless oil.

Source