反应详情

温度

25 °C

To a stirred mixture of 3,3-dimethoxybutan-2-one (J.Chem.Soc. 1953, 3135; 1.32 g., 10 m moles) and ammonium acetate (7.7 g., 0.1 mole) in methanol (30 ml.) at 25° C. was added sodium cyanoborohydride (380 mg., 6 m moles) and the pH of the mixture was reduced to 6.0 by addition of a solution of HCl in methanol. The mixture was stirred for 2 hours at 25° C. then the solvent was evaporated under reduced pressure. The residue was taken up in water and the pH adjusted to 5 with 2N aqueous HCl. The solution was washed with ether (3×20 ml.) and the pH of the aqueous phase raised to above 10 by addition of sodium carbonate. The product was extracted with ether (5×20 ml.) and the combined extracts were dried (MgSO4) and evaporated to dryness to give 1-methyl-2,2-dimethoxypropylamine (1.02 g., 77%) as a pale yellow oil having the following n.m.r. spectrum in CDCl3 : 1.05 (d, 3H); 1.2 (s, 3H); 1.6 (m, 2H); 3.25 (s, 6H); 3.0-3.6 (m, 1H).

1. customthe solvent was evaporated under reduced pressure
2. washThe solution was washed with ether (3×20 ml.)
3. temperaturethe pH of the aqueous phase raised to above 10 by addition of sodium carbonate
4. extractionThe product was extracted with ether (5×20 ml.)
5. dry with materialthe combined extracts were dried (MgSO4)
6. customevaporated to dryness