Reaktion #69611

Reaktionsgleichung

Paraformaldehyde

Triethylamine

2-phenylphenol

magnesium chloride

→

2-Hydroxybiphenyl-3-carbaldehyde

Lösungsmittel

THF

EtOAc

HCl

HCl

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeformed
2. 2
   Temperaturthe mixture heated
3. 3
   Temperaturto reflux with formation of a yellow suspension
4. 4
   TemperaturThe mixture was refluxed for 2.5 hr
5. 5
   Temperaturto slowly cool to room temperature
6. 6
   workup.STIRRINGstirred overnight
7. 7
   Temperaturwith mild cooling
8. 8
   Sonstigeat <25° C
9. 9
   SonstigeThe mixture was transferred to a separatory funnel
10. 10
    WaschenThe organic phase was washed with brine (300 mL)
11. 11
    Trocknendried over Na2SO4
12. 12
    Filtrationfiltered
13. 13
    Einengenthe solution concentrated under reduced pressure
14. 14
    Sonstigegiving a yellow oil
15. 15
    Sonstigethat partially crystallized
16. 16
    workup.WAITThe oily crystalline material was pumped on high vacuum for 1 hr
17. 17
    Sonstigeto give 20.6 g (104%) of crude 14 that
18. 18
    Sonstigewas used without further purification

Vorschrift

Triethylamine (20.2 g, 27.8 mL, 0.20 mol, 2.0 equiv) was added to a solution of 2-phenylphenol (13) (17.0 g, 0.10 mol, 1.0 equiv) in THF (200 mL) followed by solid magnesium chloride (14.3 g, 0.15 mol, 1.5 equiv). The reaction temperature increased from 23 to 40° C. over ˜10 min. The reaction mixture was stirred an additional 10 min during which time a light tan suspension formed. Paraformaldehyde (15.0 g, 0.5 mol, 5.0 equiv) was added and the mixture heated to reflux with formation of a yellow suspension. The mixture was refluxed for 2.5 hr, allowed to slowly cool to room temperature and stirred overnight. The mixture was diluted with EtOAc and 1N HCl (300 mL) with mild cooling to keep the reaction temperature at <25° C. The mixture was transferred to a separatory funnel and shaken with an additional 1N HCl (200 mL). The organic phase was washed with brine (300 mL), dried over Na2SO4, filtered and the solution concentrated under reduced pressure giving a yellow oil that partially crystallized. The oily crystalline material was pumped on high vacuum for 1 hr to give 20.6 g (104%) of crude 14 that was used without further purification.

Quelle