Non‐Noyori‐Type Ruthenium‐POP Pincer Catalysts in Ethanol Upgrading

Butanol is one of the most promising candidates for replacing gasoline fuel in future grid‐independent applications. In this study, we report the synthesis and analysis of new ruthenium‐POP pincer complexes of the general formula [RuHCl(POP)(PPh 3 )] using commercially available or easy‐to‐synthesize tridentate POP pincer ligands, all derivatives of xantphos, DPEphos, (diphosphino)diethyl ether, and DBFphos. Their analytical properties were found to show clear trends in relation to the electronic and steric properties of the ruthenium center and ligand framework. We applied the complexes in the Guerbet‐type upgrading of ethanol toward 1‐butanol and higher linear alcohols, reaching up to 28% yield of 1‐butanol at 120 °C for 48 h.