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The use of Activated Carboxylic Acids (ACAs) allows the time‐controlled operation of dissipative chemical systems based on the acid‐base reaction by providing both the stimulus that temporarily drives a physicochemical change and, subsequently, the counter‐stimulus with a single reagent addition. However, their application is inherently limited to acid‐sensitive systems. To overcome this limitation, we herein develop a straightforward device for the transduction of the acid‐base stimuli delivered by an ACA into a voltage signal that, in turn, is used to control voltage‐sensitive circuits that are not pH‐responsive by themselves. The signal transductor can be easily assembled from common laboratory equipment and employs aqueous solutions of readily available chemicals. Furthermore, the operator can simply and intuitively tune the amplitude of the voltage signal, as well as its duration and offset by varying the concentration of the chemical species involved in the transduction process. [ABSTRACT FROM AUTHOR]

The oxidation of a series of alkyl aryl sulfides promoted by the phthalimide N-oxyl radical (PINO) has been investigated by kinetic and product analysis. Sulfoxides are formed as major reaction products in the oxidation of thioanisoles and benzyl phenyl sulfides. The observation of fragmentation products in the oxidation of 2-phenyl-2-propyl phenyl sulfide and diphenylmethyl phenyl sulfide indicates that the reaction involves an initial electron transfer reaction from the sulfide to PINO with the formation of aryl sulfide radical cations and the anion PINO-. Combination of the species then leads to a radical adduct precursor of sulfoxides while the rapid C–S cleavage occurs with aryl sulfide radical cations that can form the stable 2-phenyl-2-propyl or diphenylmethyl carbocation. [ABSTRACT FROM AUTHOR]

In this perspective, two different classes of multidentate ligands (aminotriphenolate and dipyridinimine) and the corresponding metal (Ti, V, Mo, W, Fe) complexes are described. These catalysts can activate efficiently the environmental benign H2O2 oxidant, promoting a wide variety of oxidative processes (sulfoxidations, N‐oxidations, epoxidations, haloperoxidation, alcohol oxidation, hydroxylation). [ABSTRACT FROM AUTHOR]

The reactivity of the phthalimide-N-oxyl radical (PINO) toward the NO-methyl C-H bond of a number of 4-X-substituted N,N-dimethylanilines is investigated. It is found that the PINO is very reactive toward the methyl C-H bond of N,N-dimethylanilines promoting the oxidative N-demethylation of the substrate.

Ketyl radicals with lignin related structures are generated by means of radiation chemical and photochemical techniques. The high reactivity of ketyl radicals with oxygen coupled with the low rates of beta-fragmentation of the same species play an important role in the photoyellowing of lignin containing pulps and papers.

Research has been conducted on the ring-methoxylate diarylmethane and diarylmethanol radical cations. The reactivities and properties of these compounds generated in aqueous solution via pulse and gamma-radiolysis have been investigated and the results of the studies are reported.

The satisfactory rationalization of complex reactive pathways in solution chemistry may greatly benefit from the combined use of advanced experimental and theoretical complementary methods of analysis. In this work, we combine X‐Ray Absorption and 1H NMR spectroscopies with state‐of‐the‐art Multivariate Curve Resolution and theoretical analyses to gain a comprehensive view on a prototypical reaction involving the variation of the oxidation state and local structure environment of a selected metal ion coordinated by organic ligands. Specifically, we investigate the 2‐cyano‐2‐phenylpropanoic acid reduction of the octahedral complex established by the Cu2+ ion with terpyridine to the tetrahedral complex formed by Cu+ and neocuproine. Through our interdisciplinary approach we gain insights into the nature, concentration time evolution and structures of the key metal (XAS measurements) and organic (1H NMR measurements) species under reaction. We believe our method may prove to be useful in the toolbox necessary to understand the mechanisms of reactive processes of interest in solution. [ABSTRACT FROM AUTHOR]

The intra- and intermolecular kinetic deuterium isotope effects and the effects of substituents on reactivity were determined to study the mechanistic dichotomy in the oxidative N-dealkylation of a series of N,N-dimethylanilines catalyzed by tetrakis(pentafluorophenyl)porphyrin iron(III) chloride. The findings clearly showed the validity of the kinetic deuterium isotope effect profile criterion to distinguish electron transfer from the hydrogen atom transfer mechanism in the oxidative N-dealkylation of N,N-dimethylanilines.

A kinetic and product study of the 3‐cyano‐N‐methyl‐quinolinium photoinduced monoelectronic oxidation of a series of β‐hydroxysulfoxides has been carried out to investigate the competition between Cα‐S and Cα‐Cβ bond cleavage within the corresponding cation radicals. Laser flash photolysis experiments unequivocally established the formation of sulfoxide cation radicals showing their absorption band (λmax ≈ 520 nm) and that of 3‐CN‐NMQ• (λmax ≈ 390 nm). Steady‐state photolysis experiments suggest that, in contrast to what previously observed for alkyl phenyl sulfoxide cation radicals that exclusively undergo Cα‐S bond cleavage, the presence of a β‐hydroxy group makes, in some cases, the Cα‐Cβ scission competitive. The factors governing this competition seem to depend on the relative stability of the fragments formed from the two bond scissions. Substitution of the β‐OH group with ‐OMe did not dramatically change the reactivity pattern of the cation radicals thus suggesting that the observed favorable effect of the hydroxy group on the Cα‐Cβ bond cleavage mainly resides on its capability to stabilize the carbocation formed upon this scission. [ABSTRACT FROM AUTHOR]