Dehydrogenative Coupling of Alcohols With Nitroarenes Under Ruthenium Catalysis

ABSTRACT A newly synthesized half‐sandwich arene Ru(II) complexes were explored as an efficient catalyst for the synthesis of imines via acceptorless dehydrogenative coupling (ADC) of alcohols with nitroarenes under mild conditions. The structural elucidation of the catalyst complexes was confirmed using spectral and analytical techniques. The present catalytic system enabled the efficient production of a wide range of imines in good to excellent yields up to 94%, generating water and hydrogen gas as by‐products. The influence of base, solvent, and the catalyst loading on the catalytic outcome was systematically investigated. Notably, the protocol also facilitated the coupling of various alcohols with nitrobenzene, requiring only 1 mol% of the catalyst loading. A probable mechanistic pathway involving aldehyde and aniline intermediates is proposed based on the experimental outcomes.