1,3-Dibromopropane → 4,5,6,7-Tetrahydropyrazolo[1,5-a]pyrimidine-3-carbonitrile

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of 5-aminopyrazole-4-carbonitrile (102 g) and triethylamine (316 ml) in 1,4-dioxane (2000 ml) was added 1,3-dibromopropane (115 ml), and the mixture was stirred at 95° C. for 5 days. The insoluble materials were removed by filtration, and the filtrate was concentrated in vacuo. To the residue was added 10% aqueous citric acid solution, and the mixture was extracted with chloroform. The extract was dried over anhydrous magnesium sulfate, filtered, and concentrated in vacuo. The residue was triturated with 2-propanol and dried in vacuo to give 4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidine-3-carbonitrile (8.0 g) as a solid.

Herkunft & Nachweise