Reaktion #63830

Reaktionsgleichung

4-amino-α-(4-chlorophenyl)-2-methoxybenzeneacetonitrile

hydrochloric acid

sodium acetate

ethyl (2-cyanoacetyl)carbamate

sodium nitrite

→

ethyl [2-[[4-[(4-chlorophenyl)cyanomethyl]-3-methoxyphenyl]hydrazono]-2-cyanoacetyl]carbamate

Lösungsmittel

water

water

acetic acid

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturcooled
2. 2
   workup.ADDITIONis added dropwise, during a 15 minutes period
3. 3
   Sonstigeat about 10° C
4. 4
   workup.STIRRINGUpon completion, the whole is stirred for 60 minutes
5. 5
   workup.STIRRINGstirring
6. 6
   FiltrationThe product is filtered off
7. 7
   Waschenwashed with water
8. 8
   workup.DISSOLUTIONdissolved in a mixture of trichloromethane and methanol (90:10 by volume)
9. 9
   SonstigeThe organic layer is dried
10. 10
    Filtrationfiltered
11. 11
    Sonstigeevaporated
12. 12
    SonstigeThe residue is purified by column chromatography over silica gel using
13. 13
    workup.ADDITIONa mixture of trichloromethane and methanol (95:5 by volume) as eluent
14. 14
    SonstigeThe pure fractions are collected
15. 15
    Sonstigethe eluent is evaporated in vacuo

Vorschrift

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.

Quelle