Reaktion #63833

Reaktionsgleichung

2-[4-[(4-chlorophenyl)cyanomethyl]-3-methoxyphenyl]-2,3,4,5-tetrahydro-3,5-dioxo-1,2,4-triazine-6-carboxylic acid

2-mercaptoacetic acid

→

intermediate 2

α-(4-chlorophenyl)-4-(4,5-dihydro-3,5-dioxo-1,2,4-triazin-2(3H)-yl)-3-methoxybenzeneacetonitrile

Lösungsmittel

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturAfter cooling
2. 2
   SonstigeThe aqueous phase is decanted
3. 3
   workup.STIRRINGthe remaining oil is stirred in water
4. 4
   workup.ADDITIONThe whole is treated with sodium hydrogen carbonate
5. 5
   ExtraktionThe product is extracted with a mixture of trichloromethane and methanol (90:10 by volume)
6. 6
   SonstigeThe extract is dried
7. 7
   Filtrationfiltered
8. 8
   Sonstigeevaporated
9. 9
   SonstigeThe residue is purified by column chromatography over silica gel using
10. 10
    workup.ADDITIONa mixture of trichloromethane and methanol (97:3 by volume) as eluent
11. 11
    SonstigeThe pure fractions are collected
12. 12
    Sonstigethe eluent is evaporated in vacuo
13. 13
    SonstigeThe residue is crystallized from 8 parts of acetonitrile
14. 14
    FiltrationThe product is filtered off
15. 15
    Waschenwashed with 2,2'-oxybispropane
16. 16
    Sonstigedried

Vorschrift

A mixture of 4.2 parts of 2-[4-[(4-chlorophenyl)cyanomethyl]-3-methoxyphenyl]-2,3,4,5-tetrahydro-3,5-dioxo-1,2,4-triazine-6-carboxylic acid and 13 parts of 2-mercaptoacetic acid is stirred and heated for 2 hours at 175° C. After cooling, 150 parts of water are added. The aqueous phase is decanted and the remaining oil is stirred in water. The whole is treated with sodium hydrogen carbonate. The product is extracted with a mixture of trichloromethane and methanol (90:10 by volume). The extract is dried, filtered and evaporated. The residue is purified by column chromatography over silica gel using a mixture of trichloromethane and methanol (97:3 by volume) as eluent. The pure fractions are collected and the eluent is evaporated in vacuo. The residue is crystallized from 8 parts of acetonitrile. The product is filtered off, washed with 2,2'-oxybispropane and dried, yielding α-(4-chlorophenyl)-4-(4,5-dihydro-3,5-dioxo-1,2,4-triazin-2(3H)-yl)-3-methoxybenzeneacetonitrile (intermediate 2).

Quelle