Crystal structure and Hirshfeld surface analysis of 1,2-ethylene-bis (para-methyl pyridinium) dichromate as a new selective and mild agent in oxidation of alcohols

1,2-Ethylene-bis(para-methyl pyridinium) dichromate, (C$_{14}$H$_{18}$N$_{2})$[Cr$_{2}$O$_{7}$], is used as a new oxidizing agent in conversion of some alcohols to their corresponding carbonyl compounds in CH$_{3}$CN solvent and also under solvent-free conditions. In both procedures, high conversion percentages are observed. However, a much shorter reaction time is achieved in solvent-free conditions. For allylic alcohols, the C=C bond is not oxidized and the examined saturated alcohol in this work (i.e. cyclo-hexanol) remains intact, which illustrates the mild nature of reagent used. The structure of the reagent is investigated by single-crystal X-ray diffraction analysis. The C--H$\cdots$O and O$\cdots \pi$ interactions are the most important features of crystal packing, which are visualized by the Hirshfeld surface map.