ISSN:
0170-2041
Keywords:
2-Pyrazolin-5-one derivatives
;
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
3-Methyl-1-phenyl-2-pyrazoline-4,5-dione (3) condenses readily with malononitrile in refluxing ethanol to yield 4-(dicyanomethylene)-3-methyl-1-phenyl-2-pyrazolin-5-one (4). Compound 4 readily reacts with aliphatic, aromatic, and heterocyclic amines to yield 4-substituted (aminocyanomethylene)-3-methyl-1-phenyl-2-pyrazolin-5-ones (8). o-Substituted arylamines afford also 4-substituted (arylcyanomethylene)pyrazolones, which readily cyclize to give the 4-azolylidene pyrazolones 9a-c. Secondary and tertiary amines and activated phenols condense with 4 by hydrogen cyanide elimination to yield compounds 10a-c and 10a, b, respectively.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jlac.198919890262
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