31053-93-7

Upstream product

• 5335-87-5 4,4'-dimethoxyphenyl disulfide 
• 6119-32-0 4-methoxyphenoxyl 
• 26971-83-5 4-methoxybenzenethiolate 
• 50-44-2 6H-purine-6-thione 
• 696-63-9 4-Methoxybenzenethiol 
• 1015308-23-2 [D]4-methoxythiophenol 
• 24856-47-1 3-hydroxy-phenyloxyl 

Downstream Products

• 5335-87-5 4,4'-dimethoxyphenyl disulfide 
• 84751-94-0 C₇H₇OS*C₆H₅NO 
• 24856-47-1 3-hydroxy-phenyloxyl 
• 26971-83-5 4-methoxybenzenethiolate 
• 6119-32-0 4-methoxyphenoxyl 

Relevant academic research and scientific papers

Reactivity of perfluoro-n-alkyl radicals a Hammett study of hydrogen transfer from arene thiols

A Hammett study of hydrogen atom abstraction by the perfluoro-n-heptyl radical is presented. Excellent correlation of the rates with σ+, with a ρ+ value of -0.56, provides important corroboration of the substantial influence of transition state polar effects on this unexpectedly slow process.

Understanding Chemoselectivity in Proton-Coupled Electron Transfer: A Kinetic Study of Amide and Thiol Activation

While the mechanistic understanding of proton-coupled electron transfer (PCET) has advanced significantly, few reports have sought to elucidate the factors that control chemoselectivity in these reactions. Here we present a kinetic study that provides a quantitative basis for understanding the chemoselectivity in competitive PCET activations of amides and thiols relevant to catalytic olefin hydroamidation reactions. These results demonstrate how the interplay between PCET rate constants, hydrogen-bonding equilibria, and rate-driving force relationships jointly determine PCET chemoselectivity under a given set of conditions. In turn, these findings predict reactivity trends in a model hydroamidation reaction, rationalize the selective activation of amide N-H bonds in the presence of much weaker thiol S-H bonds, and deliver strategies to improve the efficiencies of PCET reactions employing thiol co-catalysts.

Control of intramolecular orbital alignment in the photodissociation of thiophenol: Conformational manipulation by chemical substitution

(Graph Presented) Intramolecular orbital alignment can be controlled by conformational tuning of the initial wavepacket location on the two-dimensional potential-energy surfaces of thiophenol (see picture; CI = conical intersection). Chemical substitution induces conformational preference, leading to a dramatic change of the branching ratio between X and A states of the phenylthiyl radical.

Synthesis and radiation sensitivity of phenoxazine type color formers including thiol ester protective group

3,7-Bis(N,N-diethylamino)-10-(phenylthio)carbonylphenoxazine (1a) and its analogs (1b-f) were synthesized and the color change after γ irradiation was investigated. The color change of acetonitrile solutions of 1a ([1a] 0 = 1.0 × 10-3 M) after γ irradiation was identified by naked eyes at the dose of 20 Gy. Phenylthio-substituted compound la showed more significant absorbance increase than phenoxy-substituted compound, 3,7-bis(N,N-diethylamino)-10-phenoxycarbonylphenoxazine (2a). The C-S cleavage in la by γ irradiation was revealed to occur more easily than the C-O cleavage in 2a. The sensitivity of the color formers 1a-f) to γ rays was correlated with the stability of the thiyl radicals generated in the reaction.

Localized electron transfer in nonpoiar solution: reaction of phenols and thiophenols with free solvent radical cations

Free electron transfer (FET) is understood as the reaction of free and uncorrelated solvent parent radical cations with solutes characterized by a lower ionization potential than those of the solvent. We studied electron transfer from phenols and thiophen

Free electron transfer from several phenols to radical cations of non-polar solvents

Electron-transfer reactions from phenols to parent radical cations of solvents were studied using pulse radiolysis. Phenols bearing electron-withdrawing, electron-donating and bulky substituents were investigated in non-polar solvents such as cyclohexane, n-dodecane, n-butyl chloride and 1,2-dichloroethane. The experiments revealed the direct, synchronous formation of phenoxyl radicals and phenol radical cations in all cases and in nearly the same relative amounts. This was explained by two competing electron-transfer channels which depend on the geometry of encounter between the parent solvent radical cations and the solute phenol molecules. The mechanism is analysed at a microscopic level, treating diffusion as a slow process and the local electron transfer as an extremely rapid event. Furthermore, the effect of various phenol substituents and solvent types on the electron-transfer mechanism and on the decay kinetics of the solute phenol radical cations was analysed. The results were further substantiated using a quantum chemical approach.

Photochemical properties of excited triplet state of 6H-purine-6-thione investigated by laser flash photolysis

Photochemical reactions of 6H-purine-6-thione (PuT) via the excited triplet state [3(PuT)*] have been studied by means of laser flash photolysis in organic solvents. Transient absorption bands at 475 and 690 nm were assigned to 3(PuT)*. Intersystem quantum yield and the lowest triplet energy of 3(PuT)* were evaluated to be 0.99 and 63 kcal/mol, respectively. The self-quenching rate constant is quite large (2.3×109 M-1 s-1 in THF). In photoinduced electron transfer, 3(PuT)* acts as electron acceptor for tetramethylbenzidine, while 3(PuT)* acts as electron donor for p-dinitrobenzene. Rate constants for H-atom abstraction (khT) of 3(PuT)* from benzenethiols, tocopherol, and 1,4-cyclohexadiene are on the order of 108 M-1 s-1. From the Hammett plots of khT for substituted benzenethiols, a negative ρ value indicates that 3(PuT)* has electrophilic character. In the addition reaction of 3(PuT)* toward various alkenes, the electrophilic character of 3(PuT)* was also confirmed. By steady-light photolysis of PuT, purine was produced via 3(PuT)* after H-atom abstraction. On combination of these results, the character of the lowest 3(PuT)* was presumed.

Reduction potentials and kinetics of electron transfer reactions of phenylthiyl radicals: Comparisons with phenoxyl radicals

The reduction potentials relative to the standard hydrogen electrode (SHE) for a number of para-substituted phenylthiyl radicals (Eo(p-XC6H4S./p-XC6H 4S-)) have been derived from pulse radiolytic studies of electron transfer equilibria which compare their values to those of radicals of known reduction potentials. A ladder combining the reduction potentials for both phenylthiyl and phenoxyl radicals has been established. These reduction potentials have been shown to be self-consistent and are intermediate between those of p-benzosemiquinone radical anion at 0.02 V and phenoxyl radical at 0.79 V. The reduction potential decreases as the electron donating power of the para substituent rises. The substituent effect is, however, much weaker for the phenylthiyl radicals than for their oxygen analogs. These observations demonstrate that the electronic interaction between the sulfur atoms and the aromatic ring system is much less than that which occurs with oxygen atoms. Examination of the rates of electron transfer in terms of the Marcus theory indicates that the reorganization energies of both p-XC6H4O. and p-XC6H4S. radicals are similarly affected by H, CH3, and CH3O substitution. However, the reorganization energies increase substantially for H2N and O- para substituents with the effect being much less for the p-XC6H4S. radicals than for the p-XC6H4O. radicals. These observations are in accord with structural information from spectroscopic and theoretical studies of the radicals which show that in the latter system the substituent groups interact strongly with the aromatic π system.

Evaluation of dissociation energies of S-H bonds in thiophenols and thioalcohols on the basis of kinetic measurements

Kinetic data on the reactions of alkyl and benzyl radicals with thiophenol C6H5SH were analyzed within the framework of the parabolic model of transition state. The values of the parameter that establishes a correlation between the activation energy of a reaction and its enthalpy were calculated for reactions of alkyl and benzyl radicals with the C6H5SH. The equations of the parabolic model were used to calculate the bond dissociation energies for 11 thiophenols and 4 thioalcohols. The activation energies for reactions of 12 thiophenoxy radicals with cumene and of C6H5S? radical with several alkyl-aromatic hydrocarbons were obtained.

Substituent Effects on the Free-radical Addition Reactions of Arylthiyl Radicals with Arylacetylenes

Absolute rate constants for addition reactions of arylthiyl radicals (YC6H4S.) to arylacetylenes (XC6H4CCH) have been determined by a flash-photolysis method.The rate constants (in dm3 mol-1 s-1) vary from 1.