反应详情

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 0.95 g (5 mmol) of p-toluenesulfonic acid monohydrate, 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 dissolved in ethyl acetate. The solution was washed with water and 10% aqueous sodium carbonate solution to remove a residual acid component. Ethyl acetate was removed from the solution under reduced pressure, and the residue was purified by silica gel chromatography to yield 28.5 g (76 mmol) of the target 3,3′-diaminobenzidine tetraisopropanimine [N,N′,N″,N′″-tetraisopropylidene-3,4,3′,4′-biphenyltetramine] in a yield of 76%.

1. customIn a 200-ml flask equipped with a Soxhlet extractor
2. temperatureby heating
3. temperatureunder reflux in a nitrogen atmosphere for 3 hours
4. customacetone was removed under reduced pressure
5. dissolutionthe residue was dissolved in ethyl acetate
6. washThe solution was washed with water and 10% aqueous sodium carbonate solution
7. customto remove a residual acid component
8. customEthyl acetate was removed from the solution under reduced pressure
9. customthe residue was purified by silica gel chromatography