Reacción #74758

Ecuación de reacción

glyoxal

N-(3,5-bis-trifluoromethyl-phenyl)-N'-methyl-thiourea

thiourea

→

1-(3,5-bis-Trifluoromethyl-phenyl)-3-methyl-4,5-dihydroxy-imidazolidine-2-thione

Disolventes

triethylamine

1,2-dimethoxyethane

Condiciones de reacción

Tratamiento posterior

1. 1
   Concentraciónwas concentrated in vacuo
2. 2
   workup.STIRRINGthe residue was stirred with water
3. 3
   Filtraciónwas filtered off
4. 4
   Lavadowashed
5. 5
   Otrodried
6. 6
   Otromelting point: 133°-135° C. after recrystallisation from toluene

Procedimiento

30.0 g of N-(3,5-bis-trifluoromethyl-phenyl)-N'-methyl-thiourea were stirred in 100 ml of 1,2-dimethoxyethane and 10 ml of triethylamine, and then 22 g of a 30% strength aqueous glyoxal solution were added. The thiourea thereupon dissolved, the reaction being exothermic. The solution was stirred for a further 12 hours at 20° C. and was concentrated in vacuo and the residue was stirred with water and a little acetic acid. The reaction product, which had solidified, was filtered off, washed and dried. Yield 32.0 g; melting point: 133°-135° C. after recrystallisation from toluene.

Fuente