ISSN:
0021-8383
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
Synthesis and Properties of Pyrazolo[3,2-c]benzo-1,2,4-triazines and Pyrazolo [3,2-c]pyrido[4,3-e] [1,2,4]triazinesα,β-Unsaturated β-aminonitriles 1 condensate with 2-nitrophenylhydrazine and with 4-hydrazino-3-nitropyridine to yield the corresponding nitriles of β-keto acids 2 and 3, respectively. Bases achieve cyclisation of these compounds to pyrazolo[3,2-c]benzo-1,2,4-triazine-5-oxides 7 and pyrazolo[3,2-c]pyrido[4,3-e] [1,2,4]triazine-5-oxides 8, respectively. The N-oxides are reduced by means of sodium dithionite to the corresponding triazines 9, 10.
Notes:
α,β-Ungesättigte β-Aminonitrile 1 kondensieren mit 2-Nitrophenylhydra-zin und mit 4-Hydrazino-3-nitropyridin zu Hydrazonen von β-Ketosäurenitrilen 2 bzw. 3. Diese Verbindungen cyclisieren bei der Einwirkung von Basen zu Pyrazolo[3,2-c]benzo-1,2,4-triazin-5-oxiden 7 bzw. Pyrazolo[3,2-c]pyrido[4,3-e] [1,2,4]triazin-5-oxiden 8. Die N-Oxide lassen sich mittels Natriumdithionit zu den entsprechenden Triazinen 9, 10 reduzieren.
Additional Material:
4 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/prac.19763180515
Permalink