Copper(II) as the catalyst in a cross dehydrogenative coupling (CDC) reaction has been demonstrated for the synthesis of benzylic esters using aldehydes and alkylbenzenes as coupling partners.

A tandem and convergent approach to various N-, O-, or S-containing azoles has been developed by exploiting the thiophilic property of copper(I) iodide used in a catalytic quantity. The present protocol gives access to amino-substituted tetrazoles, triazoles, oxadiazoles and thiadiazoles via oxidative desulfurization of their respective precursors followed by inter-or intramolecular attack of suitable nucleophiles. For aminotetrazoles and triazoles an excellent regioselectivity has been achieved through proper tuning of the pK a values of the parent amines attached to unsymmetrical thioureas. The method represents an autocatalytic process in which copper(I) iodide gets converted to copper(II) sulfide which in turn transforms to active copper(II) oxide that effectively carries forward the catalytic cycle. The fate of the copper catalyst has also been studied using scanning electron microscopic (SEM) and energy-dispersive X-ray spectroscopic (EDS) analyses which give an insight into the mechanism for this catalytic process.

Climatic uncertainties and shortage of land expose conventional potash production from sea bittern to greater risks which the proposed route helps mitigate.

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