Reaction #312610

Reaction equation

4-bromobenzimidazole

homopiperazine

NaOt-Bu

→

4-(homopiperazin-1-yl)benzimidazole

Solvents

water

o-xylene

Conditions

Workup

1. 1
   Temperaturecooled to room temperature
2. 2
   ExtractionThe aqueous mixture is extracted with ethyl acetate
3. 3
   Dryingdried over MgSO4
4. 4
   Concentrationconcentrated in vacuo
5. 5
   Otherto give a residue
6. 6
   OtherThe residue is purified by flash chromatography

Procedure

A suspension of 4-bromobenzimidazole (42 mmol), homopiperazine (256 mmol) and NaOt-Bu (59 mmol) in dry o-xylene, under N2, is treated with a catalytic amount of Pd (OCOCH3)2·P(t-Bu)3 (P/Pd=4), heated at 120° C. for 3 hr, cooled to room temperature and diluted with water. The aqueous mixture is extracted with ethyl acetate. The extracts are combined, dried over MgSO4 and concentrated in vacuo to give a residue. The residue is purified by flash chromatography to give 4-(homopiperazin-1-yl)benzimidazole.

Source