Arenediazonium salts: new probes of the interfacial compositions of association colloids. 1. Basic approach, methods, and illustrative applications

Rates and pH-dependent product distributions of the CuCl2-catalyzed dediazoniation ofp-nitrobenzenediazonium ­tetrafluoroborate in aqueous acid

“…This low selectivity is similar to literature values of S w Cl = 3 for benzendiazonium ion, S w Cl = 4 for 2,4,6 -trimethylbenzenediazonium ion and S w Cl = 1.7 for p-methylbenzenediazonium ion. 25 The selectivities are dependent on ionic strength, as found by Chauduri et al 34 All these results are consistent with rate-determining loss of N 2 (Figs 1 and 2). ArOH is probably formed primarily by reaction of water with the 'free' arenediazonium ions.…”

Solvolysis of o-methylbenzenediazonium tetrafluoroborate in acidic methanol-water mixtures. Further evidence for nucleophilic attack on a solvent separated aryl cation

“…Only two dediazoniation products, ArOH and ArOMe, are formed and quantitative conversion to products is achieved in the entire composition range. [14].…”

“…Therefore, determination of S values at different solution compositions [4,7] can be used to provide evidence of the presence of cationic intermediates and the nature of the cationic intermediate, complementing other studies involving added nucleophilic traps, which have the disadvantage that they may induce mechanistic changes [12]. These solvolysis studies also can be of interest to those working on dediazoniations in colloidal systems like micelles [13] and microemulsions [14,15] and other macromolecular systems like crown ethers [16,17] and cyclodextrins [18]. Such systems show significant gradients of polarity [19] ongoing from the bulk phase to the core of the aggregate or show relatively hydrophobic microscopic environments [20] where arenediazonium ions can be located [13,20].…”

Electrochemical determination of rate constants and product yields for the spontaneous dediazoniation ofp-nitrobenzenediazonium tetrafluoroborate in acidic aqueous solution

“…As noted before, product yields can be estimated from the peak current values at infinite time, i.e., when dediazoniation is essentially over (98%) and a selec- [27,28,35], which range from 2 to 10 and are ionic strength dependent, and with that obtained by HPLC under similar experimental conditions [34], S W Cl ϭ 5.4. The difference in the selectivity values obtained probably stems from the slight variations in the experimental conditions and from variations in the selectivity with ionic strength [27].…”