Reacción #2298650

Ecuación de reacción

α-chloro-2-bromobenzaldehyde phenylsulfonylhydrazone

N-methylpiperazine

→

brown gum

Rendimiento 124.8%

1-[[(phenylsulfonyl)hydrazono](2-bromophenyl)methyl]-4-methylpiperazine

Rendimiento 124.8%

Disolventes

tetrahydrofuran

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.WAITto stand at ambient temperature for 16 hours
2. 2
   TemperaturaThe reaction was chilled in an ice bath
3. 3
   Filtraciónfiltered
4. 4
   Otroto remove the piperazine hydrochloride that
5. 5
   Otrowas formed
6. 6
   ConcentraciónThe filtrate was concentrated
7. 7
   Otroto yield a brown gum
8. 8
   OtroThe gum was triturated with hot acetonitrile
9. 9
   Temperaturathe mixture was cooled in an ice bath
10. 10
    Filtraciónwhen cold, was filtered
11. 11
    Otroto remove unwanted side product
12. 12
    ConcentraciónThe filtrate was then concentrated

Procedimiento

To a stirred solution, under nitrogen, of α-chloro-2-bromobenzaldehyde phenylsulfonylhydrazone (271.1 g; 0.72 mol) in tetrahydrofuran (THF; 2 liters), was added dropwise N-methylpiperazine (159.7 g; 1.6 mol). The reaction was stirred at ambient temperature for three hours, and then permitted to stand at ambient temperature for 16 hours. The reaction was chilled in an ice bath, and then filtered to remove the piperazine hydrochloride that was formed. The filtrate was concentrated to yield a brown gum. The gum was triturated with hot acetonitrile, the mixture was cooled in an ice bath, and when cold, was filtered to remove unwanted side product. The filtrate was then concentrated to afford 392.9 g of a brown gum of crude 1-[[(phenylsulfonyl)hydrazono]-(2-bromophenyl)methyl]-4-methylpiperazine.

Fuente