R. Jones, A. J. Ryan, S. Sternhell
1963
Citations
0
Influential Citations
78
Citations
Quality indicators
Journal
Tetrahedron
Abstract
Abstract Infrared and N.M.R. spectroscopy were used to assign structures to 3,4,4-trimethyl-5-pyrazolone, 3,4-dimethyl-5-pyrazolone, 3-methyl-5-pyrazolone, and their 1-phenyl analogues, 1-(p-sulphophenyl)-3-methyl-5-pyrazolone and the corresponding 3-carbethoxy and carboxy derivatives, together with 1-phenyl-3-methyl-4-phenylazo-5-pyrazolone, the corresponding 3-carboxylic acid and its methyl ester, and 1-phenyl-3-carbethoxy-4-(p-acetoxyphenylazo)-5-pyrazolone. All the above compounds exist in a keto form and the arylazo derivatives are in the form IX stabilized by strong intramolecular hydrogen bonding.