Ruthenium(II) oxidase catalysis by direct dioxygen-coupled turnover enabled step-economical oxidative C-H alkenylation reactions at ambient pressure. Versatile ruthenium(II) biscarboxylate catalysts displayed ample substrate scope and proved applicable to weakly coordinating and removable directing groups. The twofold C-H functionalization strategy was characterized by exceedingly mild reaction conditions as well as excellent positional selectivity.

Ruthenium(II) bis(carboxylate)s proved highly effective for two decarboxylative C-H alkenylation strategies. The decarboxylation proceeded efficiently at rather low temperatures. The unique versatility of the decarboxylative ruthenium(II) catalysis is reflected in the oxidative olefinations with alkenes as well as the redox-neutral hydroarylations of alkynes.

Computational studies on decarboxylative C-H alkenylations provided key insights into the solvent-robust nature of C-H activation/decarboxylation domino reactions. These properties were exploited for ruthenium(II)-catalyzed C-H alkylations by a decarboxylative process with ample scope under copper-free and silver-free reaction conditions.

Ruthenium(ii) biscarboxylate oxidase catalysis is a powerful tool for the assembly of functionalized arenes with oxygen as a green oxidant. An improved level of sustainability has been achieved with the biomass-derived GVL as solvent.

Herein we report an efficient procedure for the C–H functionalization of 1,2,3-triazoles in a continuous flow regime applied to a variety of functionalities and to the inter- or intramolecular versions of the process.