Réaction #3050

Équation de réaction

phenol

N-methylformanilide

phosphoryl chloride

Ortho-tertbutylphenol

→

3-(1,1-dimethylethyl)-4-hydroxybenzaldehyde

Solvants

—

hexanes

toluene

Conditions de réaction

Traitement

1. 1
   Températurewith cooling
2. 2
   Autrethe resulting reaction mixture
3. 3
   workup.STIRRINGwas stirred for an additional 30 minutes at room temperature
4. 4
   Températureheated to approximately 60° C.
5. 5
   workup.STIRRINGstirred for five hours at that temperature
6. 6
   workup.ADDITIONThe reaction mixture was poured into a volume of crushed ice
7. 7
   Extractionextracted with chloroform
8. 8
   AutreThe aqueous layer was separated
9. 9
   Lavagewashed again with chloroform
10. 10
    Extractionextracted with 2000 ml of a 5% potassium hydroxide solution
11. 11
    ExtractionThe aqueous potassium hydroxide extract
12. 12
    workup.ADDITIONwas then added to 1000 ml of chloroform
13. 13
    AutreThe mixture's layers were separated
14. 14
    Extractionthe aqueous layer was again extracted with chloroform
15. 15
    ExtractionThe organic layer from the two-phase mixture and the chloroform extract
16. 16
    Lavagewashed with water
17. 17
    Séchagedried over sodium sulfate
18. 18
    AutreThe volatile components of the solution were removed under reduced pressure
19. 19
    Autreto provide a residue
20. 20
    TempératureThe solution was slowly cooled to room temperature while a precipitate
21. 21
    Autreformed
22. 22
    FiltrationThis precipitate was recovered by filtration
23. 23
    Lavagewashed with hexanes
24. 24
    Autredried under vacuum
25. 25
    Autreto provide 20.0 g of the

Mode opératoire

Into 184.4 ml (1,494 mol) of N-methylformanilide were added dropwise, with cooling, 130.9 ml (1,404 mol) of phosphoryl chloride over a period of 20 minutes. The mixture was allowed to warm to room temperature and stirred for one hour. Ortho-tertbutylphenol (138.2 ml; 0.9 mol) was then added dropwise to the reaction solution over a period of 25 minutes. After phenol addition was complete, the resulting reaction mixture was stirred for an additional 30 minutes at room temperature and then heated to approximately 60° C. and stirred for five hours at that temperature. The reaction mixture was poured into a volume of crushed ice and extracted with chloroform. The aqueous layer was separated and washed again with chloroform. The chloroform layers were combined and extracted with 2000 ml of a 5% potassium hydroxide solution. The aqueous potassium hydroxide extract was then added to 1000 ml of chloroform. The pH of the resulting two-phase mixture was adjusted to approximately pH 2.0 with concentrated hydrochloric acid. The mixture's layers were separated and the aqueous layer was again extracted with chloroform. The organic layer from the two-phase mixture and the chloroform extract were combined, washed with water and then dried over sodium sulfate. The volatile components of the solution were removed under reduced pressure to provide a residue. This residue was dissolved in 100 ml of hot toluene and the resulting solution was diluted with 100 ml of hexanes. The solution was slowly cooled to room temperature while a precipitate formed. This precipitate was recovered by filtration, washed with hexanes and then dried under vacuum to provide 20.0 g of the desired substituted intermediate.

Source