Reaktion #435032

Reaktionsgleichung

ammonium chloride

triethoxyborane

3,5-dimethoxybenzyl alcohol

n-butyllithium

→

title compound

4-(Hydroxymethyl)-2,6-dimethoxyphenylboric acid

Lösungsmittel

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwhile cooling with ice with ice bath
2. 2
   TemperaturThe internal temperature was then cooled to −78° C., to the mixture
3. 3
   Temperaturthe temperature was raised to room temperature
4. 4
   workup.STIRRINGwhile stirring
5. 5
   workup.ADDITIONwas added to the reaction mixture
6. 6
   Temperaturwhile cooling with ice
7. 7
   Extraktionthe reaction mixture was extracted with ethyl acetate
8. 8
   Waschenafter washing the
9. 9
   Extraktionorganic extract with brine, it
10. 10
    Trocknenwas dried over anhydrous magnesium sulfate
11. 11
    Sonstigethe solvent was evaporated under reduced pressure
12. 12
    SonstigeThe residue was purified by silica gel column chromatography (50 g)

Vorschrift

To a solution of 3,5-dimethoxybenzyl alcohol (2.71 g) in tetrahydrofuran (50 mL) was added n-butyllithium (1.56M hexane solution; 36.2 mL)while cooling with ice with ice bath, and the internal temperature was raised to room temperature and stirred for 1 hour. The internal temperature was then cooled to −78° C., to the mixture was added triethoxyborane (9.6 mL), and the temperature was raised to room temperature while stirring. After completion of the reaction, saturated aqueous ammonium chloride was added to the reaction mixture while cooling with ice and the reaction mixture was extracted with ethyl acetate, and then after washing the organic extract with brine, it was dried over anhydrous magnesium sulfate and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (50 g) and the title compound (1.72 g) was obtained as a white amorphous solid from the ethyl acetate fraction.

Quelle