A convergent paired electrochemical method was developed for the synthesis of azoxy and azo compounds starting from the corresponding nitroarenes. We propose a unique mechanism for electrosynthesis of azoxy and azo compounds. We find that both anodic and cathodic reactions are responsible for the synthesis of these compounds. The synthesis of azoxy and azo derivatives have been successfully performed in an undivided cell, using carbon rod electrodes, by constant current electrolysis at room temperature.

Electrochemical oxidation pathway of p-chloroaniline (PCA) in the presence of benzenesulfinic acid (BSA).

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Electrochemical oxidation of propofol (2,6-diisopropylphenol) (PPF) has been studied in a water/acetonitrile (50/50, v/v) mixture by cyclic voltammetry, differential pulse voltammetry and galvanostatic coulometry. The results show that PPF can be electrochemically oxidized in a chemically irreversible one-electron/one-proton process to form the corresponding radical (PPF • ) which couples to yield propofol dimer (PD). Due to the easier oxidation of PD compared to PPF, the PD is oxidized in a reversible two-electron/two-proton process to form 3,3′,5,5′-tetraisopropyl-[1,1′-bi(cyclohexylidene)]-2,2′,5,5′-tetraene-4,4′-dione (PDQ). We call this mechanism EDE for simplicity, where E represents an electron transfer at an electrode surface and D represents a homogeneous dimerization step. We also investigated the catalytic effect of sulfite ions on the oxidation of PPF and found strong evidence to support it. The electrochemical synthesis of PDQ was successfully carried out directly using drug samples or by using commercial samples of PPF in the presence of sodium sulfite as a catalyst. The electrochemical dimerization of PPF is carried out under mild conditions at room temperature and atmospheric pressure in an undivided cell using carbon anode and stainless steel cathode, using the electrode as an electron source instead of toxic oxidants, under greener conditions.

A new solid catalyst was synthesized from an ionic liquid and heterogenised by changing anion reaction. The new heterogeneous acidic catalyst was characterized by SEM images, EDS analysis, AFM images, Ft-IR, HNMR, 13CNMR and Mass Spectroscopy. It was applied to synthesis of tri-arylmethanes throughout one-pot tri-component reactions among aromatic aldehydes, N,N-dimethylaniline and other carbonic nucleophiles such as anisole and indole. Hence, synthesis of convenient and inexpensive micro-heterogeneous catalyst was introduced, the efficiency of which was confirmed. Also, various useful products were synthesized throughout this simple and clean procedure.