Reacción #1435678

Ecuación de reacción

sodium sulfide nonahydrate

methyl 2,3-diaminobenzoate

N-acetylpiperidine-4-carbaldehyde

hydrochloricacid

→

product

Rendimiento 75.0%

Methyl 2-(N-acetylpiperidin-4-yl)benzimidazole-4-carboxylate

Rendimiento 75.0%

Disolventes

water

water

water

methanol

methanol

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.ADDITIONwere added dropwise
2. 2
   Temperaturathe whole was refluxed for 30 minutes
3. 3
   TemperaturaAfter cooling
4. 4
   Temperaturathe whole was again refluxed
5. 5
   workup.ADDITIONwere then added dropwise
6. 6
   workup.WAITthe whole was boiled for a further 10 minutes
7. 7
   TemperaturaAfter cooling
8. 8
   Otrothe reaction solution was evaporated down under reduced pressure
9. 9
   OtroThe residue obtained
10. 10
    Filtraciónfiltered
11. 11
    Extracciónwas extracted several times with ethyl acetate
12. 12
    LavadoThe combined organic phases were washed with water
13. 13
    Otrodried
14. 14
    Otroevaporated down under reduced pressure

Procedimiento

3.3 g (19.9 mmol) of methyl 2,3-diaminobenzoate were dissolved in 100 ml of methanol, and a solution of 4.0 g (25.8 mmol) of N-acetylpiperidine-4-carbaldehyde in 100 ml of methanol was added dropwise at room temperature. The whole was stirred for about 10 minutes at room temperature. Thereafter, 5.2 g (25.8 mmol) of copper(II) acetate, which was dissolved in 100 ml of water, were added dropwise and the whole was refluxed for 30 minutes. After cooling, 25 ml of concentrated hydrochloricacid were added carefully and the whole was again refluxed. 7.15 g (29.8 mmol) of sodium sulfide nonahydrate, dissolved in 100 ml of water, were then added dropwise and the whole was boiled for a further 10 minutes. After cooling, the reaction solution was evaporated down under reduced pressure. The residue obtained was dispersed in water and filtered. The filtrate was rendered alkaline with aqueous sodium bicarbonate solution and was extracted several times with ethyl acetate. The combined organic phases were washed with water, dried and evaporated down under reduced pressure. 4.5 g of the product were obtained.

Fuente