反应详情

A mixture of 4-amino-3,5-dichlorophenylglyoxal hydrate (1.18 g.) and 1,1-dimethyl-2-(2-phenylacetamido)ethylamine (1.03 g.) in methanol (20 ml.) was stirred at room temperature for 16 hours. The mixture was then filtered and the filtrate stirred vigorously during the dropwise addition of a solution of sodium borohydride (500 mg.) in water (2 ml.). After stirring for 2 hours, the mixture was acidified with concentrated hydrochloric acid to pH 2-3, and then evaporated. The solid residue was suspended in water (50 ml.) and the suspension obtained was extracted with ether (100 ml). The aqueous phase was basified to pH 12-13 by addition of aqueous ammonia solution (density 0.88), and extracted with ether (2×100 ml.). The combined extracts were dried (MgSO4) and evaporated. The resultant oil was dissolved in propan-2-ol (5 ml.) and an ethereal solution of hydrogen chloride was added to bring the pH to 2-3. Further addition of an excess of dry ether gave a precipitate (1.05 g., 43%) of 1-(4-amino-3,5-di-chlorophenyl)-2-[1,1-dimethyl-2-(2-phenylacetamido)ethylamino]-ethanol dihydrochloride (Example 1), m.p. 105°-8° C.

1. filtrationThe mixture was then filtered
2. stirringthe filtrate stirred vigorously during the dropwise addition of a solution of sodium borohydride (500 mg.) in water (2 ml.)
3. stirringAfter stirring for 2 hours
4. customevaporated
5. customthe suspension obtained
6. extractionwas extracted with ether (100 ml)
7. additionThe aqueous phase was basified to pH 12-13 by addition of aqueous ammonia solution (density 0.88)
8. extractionextracted with ether (2×100 ml.)
9. dry with materialThe combined extracts were dried (MgSO4)
10. customevaporated
11. dissolutionThe resultant oil was dissolved in propan-2-ol (5 ml.)
12. additionan ethereal solution of hydrogen chloride was added
13. additionFurther addition of an excess of dry ether