反应详情

A mixture of 44.8 g (0.2 mol) of flavanone (commercially available from Aldrich Chemical Co., Milwaukee, Wisconsin), 32.6 g (0.4 mole) of dimethylamine hydrochloride, 12.6 g (0.4 mol) of paraformaldehyde, 1 ml of concentrated HCl, and 120 ml of 2-propanol was stirred at reflux for 1 hour. The reaction was then allowed to cool to room temperature, the solvent was removed under reduced pressure and the residue partitioned between 400 ml of ether and 1 liter of 5 percent aqueous hydrochloric acid. The aqueous phase was separated, washed with 200 ml of ether, cooled and made basic with solid K2CO3. The liberated base was extracted into ether, the ether solution dried over anhydrous Na2SO4, filtered and concentrated under reduced pressure. The residue was taken up in 200 ml of ethyl acetate and treated with excess acetyl chloride and ethanol. Upon cooling, white crystals precipitated. After drying, a yield of 43.8 g of 3-dimethylaminomethyl flavanone hydrochloride, (mp 172°-174° C.) was obtained.

1. temperatureat reflux for 1 hour
2. customthe solvent was removed under reduced pressure
3. customthe residue partitioned between 400 ml of ether and 1 liter of 5 percent aqueous hydrochloric acid
4. customThe aqueous phase was separated
5. washwashed with 200 ml of ether
6. temperaturecooled
7. extractionThe liberated base was extracted into ether
8. dry with materialthe ether solution dried over anhydrous Na2SO4
9. filtrationfiltered
10. concentrationconcentrated under reduced pressure
11. additiontreated with excess acetyl chloride and ethanol
12. temperatureUpon cooling
13. customwhite crystals precipitated
14. customAfter drying