反应详情

To a mixture of 3.42 grams of dimethyl 1-(3-nitrobenzylidene)-acetonylphosphonate and 3.13 grams of 2-(N-benzyl-N-methylamino)-ethyl 3-aminocrotonate was added 50 ml of isopropanol and the mixture was heated to reflux for four hours with stirring. The reaction mixture was concentrated in vacuo, the residue was dissolved in ethyl acetate, to this was added 5% hydrochloric acid solution followed by separation, chloroform was added the lower layer followed by separation, the chloroform layer was washed with 5% calcium carbonate solution and then with water, and dried. Chloroform was evaporated in vacuo, the residue was purified by subjecting to silica gel column chromatography (100 grams of silica gel being used; eluting solution is ethyl acetate), and the resulting crystals were recrystallized from a mixture of ethyl acetate and ether to give 1.28 grams (yield 20%) of 2-(N-benzyl-N-methylamino)-ethyl 5-dimethoxyphosphinyl-2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3-carboxylate, pale yellow crystals, melting point 101°-3° C.

1. temperaturethe mixture was heated
2. temperatureto reflux for four hours
3. concentrationThe reaction mixture was concentrated in vacuo
4. dissolutionthe residue was dissolved in ethyl acetate
5. additionto this was added 5% hydrochloric acid solution
6. customfollowed by separation, chloroform
7. additionwas added the lower layer
8. customfollowed by separation
9. washthe chloroform layer was washed with 5% calcium carbonate solution
10. dry with materialwith water, and dried
11. customChloroform was evaporated in vacuo
12. customthe residue was purified
13. customthe resulting crystals were recrystallized from a mixture of ethyl acetate and ether