Multifunctional Catalysis of Nanosheet Defective Molybdenum Sulfide Basal Planes for Tandem Reactions Involving Alcohols and Molecular Hydrogen

Establishing tandem catalytic synthetic strategies based on the use of readily available, stable, and renewable feedstocks is of great significant for the sustainable advancement of chemical-related industries. The key to success largely relies on applying efficient multifunctional catalysts that allow carrying out one-pot single-step synthesis. In this work, we have demonstrated that defect-engineered basal planes of a molybdenum sulfide nanomaterial ({Mo3S4}n) offer a multifunctional catalytic platform for chemical process intensification. By applying this catalyst, besides borrowing hydrogen-type processes, herein exemplified for the thioetherification of alcohols, we have also disclosed novel and rare coupling reactions requiring hydrogen activation and alcohol dehydrogenation processes in a one-pot fashion. More specifically, oxidized nucleophiles, such as o-dinitroarenes and dinitrophenyl disulfides, are reacted with alcohols in the presence of H2 to yield respectively benzimidazoles and benzothiazoles. The uncommon catalytic reactivity of {Mo3S4}n arises from the presence of coordinatively unsaturated molybdenum and sulfide species, which work as Lewis acid and Lewis basic sites, respectively. As suggested by in situ infrared (IR) spectroscopy investigations, the alcohol dehydrogenation involves the participation of both types of active sites while the H2 dissociation takes place on coordinatively unsaturated sulfide species.