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• 81064-10-0 2,3-bis(phenylsulphonyl)-1,4-dimethylbenzene 

Relevant academic research and scientific papers

SINGLE-ELECTRONIC CLEAVAGE OF A CARBON-SULFUR BOND IN THE CATHODIC REDUCTION OF 2,3-BIS(PHENYLSULPHONYL)-1,4-DIMETHYLBENZENE IN DIMETHYL SULPHOXIDE

2,3-Bis(phenylsulphonyl)-1,4-dimethylbenzene, dissolved in dimethyl sulphoxide, undergoes a one-electron single reduction wave at -1,6 V respect to Ag-Ag(1+)(0.01M).The reduction was studied by differential pulse polarography, cyclic voltametry, and controlled-potential electrolysis.Fast chemical steps follow the initial reduction and the isolated products are 1,4-dimethyldibenzothiophene 5,5-dioxide and 1,4-dimethyl-2-(phenylsulphonyl)benzene.In some experiments small percentages of 5a,9a-dihydro-1,4-dimethyldibenzothiophene 5,5-dioxide are also obtained.The results argue in support of the electron-transfer mechanism previously proposed for the photoinduced reactions of the same substrate with sodium arenethiolates in dimethyl sulphoxide.

Electrochemical Reduction of Some o-Bis(phenylsulphonyl)benzene Derivatives. Effect of the Substrate Structure and of the Addition of Bases on the Product Distribution.

A study of the electrochemical behaviour of the o-bis(phenylsulphonyl)benzene derivatives (1a-e) in dimethyl sulphoxide containing 0.1M-tetrabutylammonium tetrafluoroborate has been undertaken.The results from cyclic voltammetry, controlled-potential electrolysis, and coulometry strongly argue in support of a mechanism involving initial formation of the radical anion (1)-. which fragments into the ? radical (2) and PhSO2-.Competing pathways for (2) are (a) intramolecular homolytic arylation eventually leading to dibenzothiophene (4) together with dihydrodibenzothiophene (5) derivatives and (b) hydrogen-atom transfer leading to monosulphones (6).The fact that compounds (1a,b) undergo mainly cyclization, whereas the hydrogen-atom transfer predominates in the case of compounds (1c,d), indicates that the structure of the starting substrate is a major governing factor for the above competition.An explanation, based on a concomitance of steric effects of the methyl groups ortho to the phenylsulphonyl substituents, is given.Experiments carried out in the presence of different bases show that the intramolecular arylation leading to the cyclized product can occur also through an unprecedented chain mechanism whose efficiency, which increases as the strength and the concentration of the base is increased, is found in turn to be dependent on the substrate structure.Finally, when arenethiolates are used as bases, a third pathways (the nucleophile-radical coupling step of the SRN1 process) is found to compete for the intermediate ? radical (2) eventually leading to sulphides resulting from the overall substitution of an arylthio for a moiety in (1).When the intramolecular cyclization does not compete efficiently almost quantitative yields of sulphides are obtained via an SRN1 route.

Electrochemical Evidence for an Unusual Base-Catalysed Chain Mechanism in an Intramolecular Homolytic Arylation

Cyclic voltammetry and controlled-potential electrolysis of the disulphone (1a) in dimethyl sulphoxide show that its transformation into the dibenzothiophene dioxide (2a), in the presence of a base, is an efficient electrocatalytic process.