反应详情

A mixture of 8 g (0.026 mol) of ethyl 4,5-diphenyl-1H-pyrazole-1-acetate of Example 1, 4.1 g (0.028 mol) of dimethylaminohexylamine and 33.3 mL (0.19 mol) of diisopropylethylamine was stirred on a steam bath under nitrogen for 18 hours. Thin layer chromatography on silica gel with 5% isopropylamine in chloroform showed incomplete reaction. Another 1 mL of dimethylaminohexylamine was added and stirring continued on a steam bath for an additional 24 hours. The reaction was stripped in vacuo, taken up in 200 mL of ether, washed two times with water, washed once with half saturated sodium bicarbonate solution, washed with water again, washed with saturated sodium chloride solution, dried over magnesium sulfate, treated with decolorizing carbon, filtered and stripped. The residue was taken up in ether and treated with a slight excess of hydrochloric acid. The hydrochloride salt was extracted into water and washed three times with ether; the water layer was chilled, and made basic with solid sodium carbonate and extracted two times with ether. The ether extracts were combined, washed once with saturated sodium chloride, dried over magnesium sulfate, treated with decolorizing carbon, filtered and stripped. The resulting residue was triturated in pentane to yield 4.14 g of N([6-(dimethylamino)hexyl]-4,5-diphenyl-1H-pyrazole-1-acetamide, mp 60°-63° C.

1. stirringstirring
2. waitcontinued on a steam bath for an additional 24 hours
3. washwashed two times with water
4. washwashed once with half saturated sodium bicarbonate solution
5. washwashed with water again
6. washwashed with saturated sodium chloride solution
7. dry with materialdried over magnesium sulfate
8. additiontreated with decolorizing carbon
9. filtrationfiltered
10. additiontreated with a slight excess of hydrochloric acid
11. extractionThe hydrochloride salt was extracted into water
12. washwashed three times with ether
13. temperaturethe water layer was chilled
14. extractionextracted two times with ether
15. washwashed once with saturated sodium chloride
16. dry with materialdried over magnesium sulfate
17. additiontreated with decolorizing carbon
18. filtrationfiltered
19. customThe resulting residue was triturated in pentane