Chemical Oxidative Condensation of Benzidine in Non-Aqueous Medium: Synthesis and Investigation of Oligomers and Polymer with Benzidine Diimine Units

The oxidative condensation of benzidine has been carried out in acetic acid media using potassium peroxydisulfate as the oxidizing agent. Using different monomer–oxidant molar ratios, benzidine dimer, trimer, and polymer have been synthesized for the first time. It was established that the polybenzidine structure is composed from a sequence of benzidinediimine and diphenylene units with amino/amino end groups and thus proves the possibility of ammonia elimination during the oxidative polymerization of aromatic diamines. The method seems to be common for the synthesis of polymers with the sequence of aromatic diimine and arylene units. TGA analysis of the obtained trimer and polymer was investigated, and the high thermostability of both the polymer and trimer was revealed. According to the obtained data, both polymer and trimer matrix decomposition started at 300 °C, and at 600 °C, 75.94% and of 69.40% of the initial weight remained, correspondingly. Conductivities of the polymer and trimer show a semiconductor-type change from temperature and after doping show an increase in conductivity up to 10−4 Sm/cm.

Cathodic electrochemiluminescence behaviour of MoS2 quantum dots and its biosensing of microRNA-21

The cathodic electrochemiluminescence (ECL) behaviour of nontoxic MoS2 quantum dots (QDs) was studied for the first time using potassium peroxydisulfate as the co-reactant.

A sulfate radical based ferrous–peroxydisulfate oxidative system for indomethacin degradation in aqueous solutions

The degradation of indomethacin (IM) by ferrous ion-activated potassium peroxydisulfate (Fe2+/PDS) was investigated.

Capto-Dative Stabilization by Thermal Oxidation of 2-Oxo-1,2,3,4-tetrahydropyrimidines

Various 4,6-diaryl substituted 2-oxo-1,2,3,4-tetrahydropyrimidines (THPMs) were oxidized to 2-oxo-1,2-dihydropyrimidines (DHPMs) by potassium peroxydisulfate (PPS) in aqueous acetonitrile solution under thermal conditions. Based on the proposed oxidation reaction mechanism by way of a radical, a capto-dative stabilized radical intermediate, among two possible formed double benzylic/allylic radical centres, governs the type of product formed. Whereas the electron-donating nature of the additional methoxy-substituent enhances the rate of oxidation, its attachment to the radical intermediate decreases the radical stability, simultaneously causing the shift of the radical centre to the capto-dative stabilized benzylic radical centre. The data of the density functional theory computational studies concerning the bond lengths to the radical centres and Mulliken population analysis support the results of the experimental work.