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A three components 1,1′-bi(2-naphthol)/reduced graphene oxide@MnO2 (BN-rGO@MnO2) nanocomposite for battery-type supercapacitor applications was successfully synthesized. This nanocomposite was synthesized through one-pot reduction of a permanganate anion (MnO4−) and non-covalently 1,1′-bi(2-naphthol)-functionalized graphene oxide (BN.GO) using pomegranate fruit extract as a green reducing agent source. The formation of nanocomposite was confirmed by UV–Vis spectroscopy, x-ray diffraction, Fourier-transform infrared (FT-IR) spectroscopy, Brunauer–Emmett–Teller (BET) analysis, scanning electron microscopy and energy-dispersive x-ray spectroscopy. The synthesized BN.rGO@MnO2 nanocomposite was characterized by FT-IR and UV–Vis spectroscopy. The capability of the BN.rGO@MnO2 nanocomposite for use as an energy storage electrode material in a supercapacitor was examined by investigating its electrochemical behavior by cyclic voltammetry (CV), electrochemical impedance spectroscopy and galvanostatic charge-discharge tests. Specific capacitance of 487 F g−1 was achieved at 2 A g−1. This nanocomposite showed 81% retention of charge storage capacity after 2000 CV cycles. The application of these battery types has been implemented in various fields including medical purposes, portable electronic devices and hybrid electrical vehicles, of which their medical utilization specifically in cardiac pacemakers has attracted considerable attention. This study holds significance in the field of materials science and nanotechnology, as it proposes a potentially eco-friendly and economical method for synthesizing materials with applications in energy storage technology. The use of herbal reductions may indicate a move towards sustainable and environmentally friendly synthesis techniques. Moreover, the successful synthesis of MnO2 nanoparticles and rGO could contribute to advancements in the development of more efficient and affordable supercapacitors, which are crucial for various energy storage applications. [ABSTRACT FROM AUTHOR]

In this work, a novel series of N and S-alkylated derivatives of 1-phenyl tetrazole-5-thione were synthesized by Michael addition in organic salt media TBAB (Tetrabutylammonium bromide) using inorganic base K2CO3 under solvent-free conditions. The new and conveniently synthesized products showed unusual regioselectivity during the reaction. S-Michael adducts via reaction between 1-phenyl tetrazole-5-thione and acrylic esters as well as acrylonitrile were afforded at room temperature and N-Michael adducts obtained at 70°C. Both reactions occurred within 24 h. Surprisingly, using fumarate esters as Michael acceptor proceeded a SN2 reaction at 100°C due to steric effects. The structures of products all were confirmed by 1H and 13C NMR spectra and target compound yields were good to excellent. [ABSTRACT FROM AUTHOR]

A new series of spiro[[1,3]dithiolane-2,3′-indolines]-2′-one derivatives was synthesized using Michael addition reaction of spiro[[1,3]dithiolane-2,3′-indolin]-2′-one to various α,β-unsaturated esters as well as direct alkylation of this compound with alkyl dihalides. Michael reaction of spiro[[1,3]dithiolane-2,3′-indolin]-2′-one and α,β-unsaturated esters produced related Michael adduct in the presence of tetrabutylammonium bromide and base 1,4-diazabicyclo[2.2.2]octane in good to excellent yields at 80°C under solvent-free conditions. Also, direct alkylation of spiro[[1,3]dithiolane-2,3′-indolin]-2′-one by dihaloalkanes in the presence of base K2CO3afforded the corresponding products in good yields under the same conditions. [ABSTRACT FROM PUBLISHER]

A regioselectiveN3-alkylation of 5,5-diphenyl-2-thiohydantoin (2-thiophenytoin) using a very efficient mild base K2CO3and α,β-unsaturated esters in the presence of organic salt TBAB (tetrabutylammonium bromide) at room temperature has been reported (3b–3h). The selectivity of this reaction is excellent and products have been produced in good yields under solvent-free conditions. The increase of the reaction temperature to 70°C mostly disappeared this selectivity and afforded only theN1,N3-dialkylated derivatives of 2-thiophenytoin in good yields (4b–4g). We were unable to selectivelyN3-alkylate 2-thiophenytoin with ethyl acrylate at both room temperature and 70°C under the same conditions (4a). Dimethyl and diethyl fumarates cannot work as Michael acceptors and were hydrolyzed to fumaric acid under reaction conditions. [ABSTRACT FROM PUBLISHER]