Reaction #543546

Reaction equation

acetic acid

3,3′-diaminobenzidine

→

3,3′-diaminobenzidine monoisopropanimine

3,3′-diaminobenzidine diisopropanimine

Solvents

acetone

Conditions

Workup

1. 1
   OtherIn a 200-ml flask equipped with a Soxhlet extractor
2. 2
   Temperatureby heating
3. 3
   Temperatureunder reflux in a nitrogen atmosphere for 3 hours
4. 4
   Otheracetone was removed under reduced pressure
5. 5
   Otherthe residue was purified by silica gel chromatography

Procedure

In a 200-ml flask equipped with a Soxhlet extractor including molecular sieves 4A as a dehydrating agent, a stirrer, a condenser and a thermometer were placed 21.4 g (100 mmol) of 3,3′-diaminobenzidine, 100 ml of acetone and 3.0 g (50 mmol) of acetic acid, followed by heating under reflux in a nitrogen atmosphere for 3 hours. After cooling to room temperature, acetone was removed under reduced pressure, and the residue was purified by silica gel chromatography to yield 16.5 g (65 mmol) of 3,3′-diaminobenzidine monoisopropanimine [N′-isopropylidene-3,4,3′,4′-biphenyltetramine] and 4.7 g (16 mmol) of 3,3′-diaminobenzidine diisopropanimine [N′,N′″-diisopropylidene-3,4,3′,4′-biphenyltetramine].

Source