76426-56-7Relevant academic research and scientific papers
Studies on Paraionic Compounds. Anhydro-1-hydroxy-3-oxopyrazolopyrazolium Hydroxides. Formation and Stability of a Novel Series of 4n? Heterocyclic Betaines.
Zvilichovsky, Gury,David, Mordechai
, p. 295 - 300 (2007/10/02)
Different substituted anhydro-1-hydroxy-3-oxopyrazolopyrazolium hydroxides were prepared by the reaction of 1,3-dicarbonyl compounds with derivatives of 4-phenyl-3,5-dihydroxypyrazole.These diazapentalene derivatives belong to new series of 4n? cyclic betaines which are named "paraionic" heterocycles.The effects of substituents on the stability of both the anionic and the cationic rings were kinetically studied.Selective cleavage of either the anionic or the cationic ring was achieved by varying the conditions of the reaction with morpholine.Electron releasing groups on the cationic ring and electron attracting groups on the anionic ring enhance the stability of the bicyclic system.They also cause a hypsochromic shift of the visible light absorption.
Mesoionic 4n ?-Heterocycles, I Mesoionic 4? Five-Membered Heterocycles and 8?-Heteropentalenes. Development of the Systems and Investigations on the 1-Oxo-1H-pyrazolopyrazol-4-ium-3-olate Type
Friedrichsen, Willy
, p. 1002 - 1008 (2007/10/02)
4n ?-Mesoionic heterocycles are - with one exception - a hitherto unknown class of compounds.In this paper the possible 4 ?-five-membered mesoionic heterocycles, their ring anellated derivatives and the corresponding heteropentalenes are derived.Reactions
