Hydrochloric Acid → 2-Methyl-2-phenylpropanal

To a solution of 2-methyl-2-phenylpropanenitrile (290 g, 2.00 mol) in hexane (2000 mL) at 0° C. under N2 is added diisobutylaluminum hydride (DIBAL-H) (2600 mL, 1M in hexane) over a period of 80 minutes. The reaction mixture is stirred at 6–14° C. for 15 minutes, then allowed to warm to room temperature and stirred for 4 hours. The reaction mixture is cooled to 0° C. and H2O (50 mL) is added slowly during 1 hour. Aqueous HCl (900 mL, 15%) is then added slowly to maintain a gentle reflux. The reaction mixture is stirred for 17 hours and the organic phase is separated. The aqueous layer is extracted with ethyl acetate (400 mL) and the combined organic layers are washed with water (300 mL), brine (300 mL) and dried over Na2SO4. The organic extracts are filtered and concentrated to give 2-methyl-2-phenylpropanal as an oil (275 g, 92.8% yield, 98.2% by HPLC area).

1. stirringstirred for 4 hours
2. temperatureThe reaction mixture is cooled to 0° C.
3. temperatureto maintain a gentle reflux
4. stirringThe reaction mixture is stirred for 17 hours
5. customthe organic phase is separated
6. extractionThe aqueous layer is extracted with ethyl acetate (400 mL)
7. washthe combined organic layers are washed with water (300 mL), brine (300 mL)
8. dry with materialdried over Na2SO4
9. filtrationThe organic extracts are filtered
10. concentrationconcentrated

ORD-Eintrag

ord-265cf475ddee42328a84105d9d35affc

Quelldatensatz

uspto-grants-2006_07

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07078572B2