Reaction of several heteroarylhydrazines withbeta-diketones has been incorrectly reported togeneratetriazepines or diazepines.It has now been firmly established that these reactions lead to the formation of pyrazoles.Further,many workers have reported the formation of pyrazoles in the reaction of heteroarylhydrzaines with trifluoromethyl 1,3-diketones,whereas the actual products were found to be 5-hydroxy-5-trifluoromethyl-4,5-dihydro-1H-pyrazoles.Itwasalso establshed that iwth a trifluoromethyl beta-diketone and hydrazines,the location of the CF_3 group at position 3 or 5 pyrazoles depends on the nature of the hydrazine.Erroneous reports concening the structure of the products obtained by the reaciton of dehydroacetic acid withhydrazines have also been revised.
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