Correlation of ¹³C and ¹⁵N nuclear magnetic resonance chemical shifts with polarographic reduction potentials of para-substituted benzenediazonium salts and their electronic structures

Abstract

. Can. J. Chem. 62, 92 (1984). Carbon-13 and nitrogen-15 nmr chemical shifts of benzenediazonium salt and its para-substituted derivatives have been measured in sulfolane solutions. The chemcial shifts of I3C 1 correlate linearly with the polarographic half-wave potentials. This relation indicates the linear increase of electron densities at Cl with the increase of electron-donating power of the substituents. Non-linear relationships between "N shifts of both nitrogen nuclei and the half-wave potentials were partly attributed to the second-order paramagnetic contributions to the I5N shifts. This contribution is approximately proportional to the inverse of the uv absorption frequencies. Overall results suggest that in the ground state resonance structures of the benzenediazonium salts, the rehybridization of the Cl-Nl bond is very unlikely and this bond remains as a single bond.

Spectroscopic evidence for an aryldiazonium salt formed via the action of sodium nitrite on N-acetyltyrosine and tyrosyl groups of bovine serum albumin

“…nance of the N-acetyl groups present. The two remaining lines, similar to those obtained for 14N and in agreement with the literature (Duthaler et al, 1978;Elofson et al, 1984), clearly indicate the presence of a diazonium salt derivative of Ñ-AcTyr.…”

“…Comparison of the results given in Table I with the literature (Duthaler et al, 1978; Elofson et al, 1984) and in particular the presence of quaternary carbons at 94 and 168 ppm enable the following diazonium structure to be proposed:…”

“…Interestingly, other groups (Duthaler et al, 1978; Korzeniowski et al, 1981; Olah and Grant, 1975; Casewit et al, 1982; Elofson et al, 1984) reported the detection of nitrogen resonances in this same region, when they analyzed the structure of aromatic diazonium salts via 15N and 13C NMR. Chemical shifts of -130 ppm ^ ( ( )) 5 -150 ppm and -30 ppm 5 ( ( )) 5 -70 ppm were reported for compounds of the type…”

Real-Time High-Sensitivity Reaction Monitoring of Important Nitrogen-Cycle Synthons by 15N Hyperpolarized Nuclear Magnetic Resonance

“…When this process was repeated with aniline-15 N, the reaction monitoring step revealed the detection of hyperpolarized responses for both of the 15 N centers in the diazo product at δ N 315.0 and 232.6 in agreement with the literature (Figure 4a). 106 The hyperpolarization of both of the 15 N sites happens even though aniline itself was not hyperpolarized. Consequently, efficient polarization transfer between them takes place during their time as a coupled spin pair at low field.…”

The crystal structure of p-diethylaminobenzenediazonium hexafluorophosphate

“…Subsequently, X-ray studies have consistently shown the N-N distance, regardless of subst~tution patterns pr the nature of the anion, remains in the range I .O8 to 1.14 A, which is indicative, when compared to the dinitrogen distance of 1.097 A ( l ) , of the N-N triple bond remaining largely intact in the ground state. In recent years "C and ''N I I nmr studies (2,3) have suggested that resonance form "D" is a major contributor to the ground state. An important com-…”