反应详情

A mixture of 300 mg of 6-phenyl-8-chloro-4H-s-triazolo[4,3-a][1,4]benzodiazepine-1-methanol, 0.57 g of dicyclohexyl-carbodiimide, 45 mg of phosphoric acid and 3 ml of abs. dimethylsulphoxide is stirred for 6 days at 25° and for a further 2 days at 70°-80°. Methylene chloride is then added, the organic phase washed with water and saturated sodium chloride solution, dried over magnesium sulphate and concentrated by evarporation. Crude 6-phenyl-8-chloro-4H-s-triazolo[4,3-a][1,4]benzodiazepine-1-carboxaldehyde is obtained, which is dissolved in 5 ml of ethanol. An addition is made to the obtained solution of 100 mg of p-toluenesulphonic acid, and the mixture refluxed for 10 hours. The solution is concentrated in vacuo. The residue is taken up in methylene chloride, the organic phase washed with 5% aqueous potassium carbonate solution and with saturated sodium chloride solution, dried over sodium sulphate, and concentrated by evaporation. The residue is recrystallised from ethyl acetate/ether/petroleum ether to obtain 6-phenyl-8-chloro-4H-s-triazolo[4,3-a][1,4]benzodiazepine-1-carboxaldehyde-diethylacetal, M.P. 133°-135°.

1. washthe organic phase washed with water and saturated sodium chloride solution
2. dry with materialdried over magnesium sulphate
3. concentrationconcentrated by evarporation
4. customCrude 6-phenyl-8-chloro-4H-s-triazolo[4,3-a][1,4]benzodiazepine-1-carboxaldehyde is obtained
5. additionAn addition
6. temperaturethe mixture refluxed for 10 hours
7. concentrationThe solution is concentrated in vacuo
8. washthe organic phase washed with 5% aqueous potassium carbonate solution and with saturated sodium chloride solution
9. dry with materialdried over sodium sulphate
10. concentrationconcentrated by evaporation
11. customThe residue is recrystallised from ethyl acetate/ether/petroleum ether