Dediazoniations of Arenediazonium Ions in Homogeneous Solution. Part XIV. ¹⁵N‐CIDNP. Investigation of the reactions of diazonium ions in weakly alkaline aqueous solutions

Abstract

SummaryI5N-CIDNP. spectra recorded during the reaction of diazonium cations with OH-in weakly alkaline aqueous solutions show that the dediazoniation is at least partially homolytic. The polarizations observed for the diazonium and transdiazotate ions can be explained by reaction proceeding via a cage involving diazenyl and diazotate radicals using Kuptein's rules and simple intensity considerations.

Dediazoniation of Arenediazonium Ions in Homogeneous Solutions. Part XVII. Kinetics and mechanisms of dediazoniation of p‐chlorobenzenediazonium tetrafluoroborate in weakly alkaline aqueous solutions in the presence of oxygen

“…The kinetic results are interpreted in conjunction with data concerning the reaction products [2] and a I5N-CIDNP. investigation of a related system [3]. Specific radical chain mechanisms are consistent with the results.…”

“…-In previous papers we have described investigations of the structure and distribution of products formed in dediazoniations of p-chlorobenzenediazonium ions in weakly alkaline aqueous solutions in the presence and absence of 0, [2] and also the kinetics and mechanisms of these systems under N2 (< 5 ppb of 0,) [ 11 [3]. The analyses of the decomposition products [2] indicate that the mechanism of dediazoniations under these conditions is influenced by 0, present in the solution and in the supernatant atmosphere.…”

“…Two kinetic runs of the dediatoniation of p-chlorobenzenediatonium tetrafluoroborate in aqueous hydrogen carbonate buffer (pH 9.005 0.02; I=O.lO, T=20.0+0.1"; under Nz (60 to 100ppbof Q) in a Teflon vessel) 3) We thank Dr. W. Schwarz for these 02-determinations; see also [I]. The rate constants calculated for the straight parts of the two curves in Figure 3 are kOb,=(4.55+0.08)x Sodium tetrafluoroborate has no influence on the rate constants if the ionic strength is kept constant.…”

Dediazoniation of Arenediazonium Ions in Homogeneous Solutions. Part XVI. Kinetics and mechanisms of dediazoniation of p‐chlorobenzenediazonium tetrafluoroborate in weakly alkaline aqueous solutions under nitrogen gas

“…For the same reason we will not discuss if our CIDNP. results [4] are compatible in principle with a chain mechanism. This problem was discussed briefly by Gragerov et al [22].…”

“…data of such systems [4]. The complex problem of the reaction mechanism is therefore approached from three sides, namely by measurement of the kinetics of the decrease in the diazonium ion concentration, analysis of steady-state intermediates with the help of CIDNP., and product analysis.…”