反应详情

To a stirred and cooled (5°-10° C.) mixture of 5.6 parts of 4-amino-α-(4-chlorophenyl)-2-methoxybenzeneacetonitrile, 6.2 parts of concentrated hydrochloric acid and 50 parts of acetic acid is added dropwise, during a 15 minutes period, a solution of 1.25 parts of sodium nitrite in 10 parts of water at about 10° C. Upon completion, the whole is stirred for 60 minutes and then 3.6 parts of anhydrous sodium acetate and 2.8 parts of ethyl (2-cyanoacetyl)carbamate are added and stirring is continued for 2 hours at room temperature. The reaction mixture is poured into 250 parts of water. The product is filtered off, washed with water and dissolved in a mixture of trichloromethane and methanol (90:10 by volume). The organic layer is dried, filtered and evaporated. The residue is purified by column chromatography over silica gel using a mixture of trichloromethane and methanol (95:5 by volume) as eluent. The pure fractions are collected and the eluent is evaporated in vacuo, yielding ethyl [2-[[4-[(4-chlorophenyl)cyanomethyl]-3-methoxyphenyl]hydrazono]-2-cyanoacetyl]carbamate.

1. temperaturecooled
2. additionis added dropwise, during a 15 minutes period
3. customat about 10° C
4. stirringUpon completion, the whole is stirred for 60 minutes
5. stirringstirring
6. filtrationThe product is filtered off
7. washwashed with water
8. dissolutiondissolved in a mixture of trichloromethane and methanol (90:10 by volume)
9. customThe organic layer is dried
10. filtrationfiltered
11. customevaporated
12. customThe residue is purified by column chromatography over silica gel using
13. additiona mixture of trichloromethane and methanol (95:5 by volume) as eluent
14. customThe pure fractions are collected
15. customthe eluent is evaporated in vacuo