Reaction #2171030

Reaction equation

potassium carbonate

1,3-bis-(5-benzylamino-3-bromo-4-nitropyrazol-1-yl)propane

phenyl boric acid

→

yellow product

Yield 81.8%

1,3-bis-(5-benzylamino-4-nitro-3-phenyl-pyrazol-1-yl)propane

Yield 81.8%

Solvents

water

1,2-dimethoxyethane

Conditions

Workup

1. 1
   OtherThe resulting reaction mixture
2. 2
   Temperatureis subsequently heated
3. 3
   Temperatureunder reflux under nitrogen
4. 4
   TemperatureAfter five hours the reaction mixture is heated over silica gel (hyflo super-gel of Celite Co.)
5. 5
   Filtrationfiltered
6. 6
   Temperaturethe filtrate cooled in an ice bath
7. 7
   FiltrationThe precipitate coming down is filtered
8. 8
   Washwashed with water
9. 9
   Otherrecrystallized from 50 ml ethanol
10. 10
    OtherAfter drying in vacuum at 60° C. one

Procedure

3.7 g of 1,3-bis-(5-benzylamino-3-bromo-4-nitropyrazol-1-yl)propane from step 5.2 in 40 ml 1,2-dimethoxyethane are mixed under nitrogen with 3.8 g phenyl boric acid, 1.2 g of tetrakis(triphenylphosphin)palladium (0) and a solution of 8.3 g of potassium carbonate in 30 ml water. The resulting reaction mixture is subsequently heated under reflux under nitrogen. After five hours the reaction mixture is heated over silica gel (hyflo super-gel of Celite Co.), filtered and the filtrate cooled in an ice bath. The precipitate coming down is filtered, washed with water and recrystallized from 50 ml ethanol. After drying in vacuum at 60° C. one obtains 1.5 g of a yellow product.

Source