反应详情

A sample of 2-[[7-chloro-5-(o-chlorophenyl)-3H-1,4-benzodiazepin-2-yl]amino]propionaldehyde dimethyl acetal (2.03 g., 5.00 mmol), dissolved in 60 ml. of monoglyme, is treated with 0.75 ml. (1.30 g., 6.85 mmol) of (reagent-grade) titanium tetrachloride. A vigorous reaction takes place and a brown solid precipitates in the reaction flask. The mixture is refluxed under nitrogen for 4 hours. The reaction mixture is cooled to room temperature, poured into 250 ml. of cold 5% aqueous sodium hydroxide and extracted with chloroform (400 ml.). The chloroform layer is washed with brine, dried over anhydrous magnesium sulfate and concentrated in vacuo to a solid. After crystallization 960 mg. of 8-chloro-2-methyl-6-(o-chlorophenyl)-4H-imidazo[1,2-a][1,4]-benzodiazepine of melting point 169.5° -170.5° C. is obtained.

1. customA vigorous reaction
2. customa brown solid precipitates in the reaction flask
3. temperatureThe mixture is refluxed under nitrogen for 4 hours
4. additionpoured into 250 ml
5. extractionof cold 5% aqueous sodium hydroxide and extracted with chloroform (400 ml.)
6. washThe chloroform layer is washed with brine
7. dry with materialdried over anhydrous magnesium sulfate
8. concentrationconcentrated in vacuo to a solid
9. customAfter crystallization 960 mg