Popis: |
In this paper, syntheses of 4-amino-3,5-dinitropyrazole from four different starting materials are described. The starting materials were 4-nitropyrazole, 4-nitro-3,5-dimethylpyrazole, 3,5-dinitropyrazole, and 4-chloropyrazole, respectively. They are compared in terms of yield, number of steps and suitability for scale-up into pilot scale production. The overall yield, calculated from commercially available starting materials, ranged from 21% in the case of synthesis via 3,5-dinitropyrazole up to 61% for the one starting from 4-chloropyrazole. With numerous factors taken into account, the latter was chosen for a pilot scale study and the product could be produced in batches of 200 g. |