Beschreibung:
<jats:title>Abstract</jats:title><jats:p><jats:sup>15</jats:sup>N NMR spectra of phenylhydrazine and of 14 <jats:italic>para</jats:italic>‐ and <jats:italic>meta</jats:italic>‐substituted phenylhydrazines were measured at natural isotope abundance in DMSO‐<jats:italic>d</jats:italic><jats:sub>6</jats:sub> solution. The substituent present exerts a larger influence on the chemical shift of the nitrogen atom directly bound to the aromatic ring (N‐1) than on the second one (N‐2), which shows an attenuated and inverted trend. The chemical shifts of N‐1 and N‐2 give a good cross correlation in both series of compounds if <jats:italic>p</jats:italic>‐NO<jats:sub>2</jats:sub> and <jats:italic>m</jats:italic>‐F derivatives are excluded from the correlations of <jats:italic>para</jats:italic>‐ and <jats:italic>meta</jats:italic>‐substituted phenylhydrazines, respectively. Moreover, N‐1 SCS values show good linear correlations with Hammett substituent constants, with SCSs of directly bound hydrogen (H‐1) and with aniline nitrogen SCSs. The results of dual substituent parameter analysis are also reported together with a comparison of <jats:sup>13</jats:sup>C and <jats:sup>15</jats:sup>N chemical shifts with those of monosubstituted benzenes and substituted anilines.</jats:p>