Réaction #83911

Équation de réaction

water

vanillin

K2CO3

1-bromo-3-chloropropane

→

4-(3-chloropropoxy)-3-methoxybenzaldehyde

Rendement 37.0%

Solvants

acetone

acetone

Conditions de réaction

Traitement

1. 1
   Températurerefluxed for 0.5 hours
2. 2
   TempératureHeating
3. 3
   Autrewas removed
4. 4
   workup.STIRRINGThe reaction was stirred
5. 5
   Températurerefluxed for 16 hours
6. 6
   ExtractionThe aqueous mixture was extracted with diethyl ether
7. 7
   Séchagethe extract was dried (MgSO4)
8. 8
   Concentrationthe solution was concentrated
9. 9
   Autreto afford an oil, which upon evacuation
10. 10
    Autrechromatographed on silica gel with 50% ethyl acetatehexane as eluent

Mode opératoire

A mixture of vanillin (30.4 g, 200 mmol), K2CO3 (27.6 g) and acetone (150 ml) was stirred and refluxed for 0.5 hours. Heating was removed and 1-bromo-3-chloropropane (40.8 g, 260 mmol) in acetone was added dropwise. The reaction was stirred and refluxed for 16 hours, and then it was poured into water. The aqueous mixture was extracted with diethyl ether, the extract was dried (MgSO4), and the solution was concentrated to afford an oil, which upon evacuation solidified to a white solid (50.2 g). An 8.0 g sample was flash chromatographed on silica gel with 50% ethyl acetatehexane as eluent. Concentration of appropriate fractions gave 2.7 g (37%) of 4-(3-chloropropoxy)-3-methoxybenzaldehyde as a white solid, m.p.=53°-55° C.

Source