The utility and selectivity of the newly synthesized dinuclear arene Ru(II) complex were demonstrated towards the synthesis of imines from coupling of alcohols and amines in the aerobic condition. Analytical and various spectral methods have been used to establish the unprecedented formation of the new thiolato‐bridged dinuclear ruthenium complex. The molecular structure of the titled complex was evidenced with aid of X‐ray crystallographic technique. A wide range of imines were obtained in good‐to‐excellent yields up to 98% and water as the by‐product through an acceptorless dehydrogenative coupling of alcohols with amines. The catalytic reaction operated a concise atom economical without any oxidant with 1 mol% of the catalyst load. Further, the role of base, solvent and catalyst loading of the coupling reaction has been investigated. A plausible mechanism has been described and was found to proceed via the formation of an aldehyde intermediate. Short synthesis of antibacterial drug N‐(salicylidene)‐2‐hydroxyaniline illustrated the utility of the present protocol.

A series of biologically important 2-amino-4H-chromenes functionalized with different substituents has been synthesized through one-pot multicomponent reaction catalysed by p-cymene Ru(II) organometallic complexes encompassing N˄O chelated carbazole based hydrazone ligands....

We report a selective and sustainable synthesis of substituted pyrazoles via an eco-friendly acceptorless dehydrogenative annulation (ADA) of greener alcohols, malononitrile, and various aromatic hydrazides by newly synthesized binuclear Ru(II) p-cymene complexes. A discrete set of binuclear Ru(II) complexes are fabricated and structurally characterized by analytical, spectral, and single-crystal X-ray diffraction methods. Further, the catalytic effectiveness of the complexes is explored for the construction of 5amino-4-cyano-N-aroylpyrazoles (34 examples) under mild conditions and produces H 2 O/H 2 as the only byproduct. A sequence of polysubstituted pyrazoles has been constructed in 62−95% yield using 1 mol % catalyst loading. Probable intermediates detected in the catalytic reaction have been isolated and confirmed by nuclear magnetic resonance and electrospray ionization mass spectrometry studies. Expediently, a therapeutically significant gout medicine "allopurinol" analogue has been derived successfully from the synthesized 5-amino-4-cyano-N-aroylpyrazoles.

An efficient and selective E‐olefination of alkyl‐substituted quinolines and pyrazines through acceptorless dehydrogenative coupling of alcohols catalysed by Ru(II)–N^N^O pincer‐type complexes encompassing carbonyl and triphenylarsines as co‐ligands is demonstrated. An array of Ru(II) catalysts has been synthesized and evaluated by analytical and spectral methodologies. The solid‐state molecular structure of the synthesized complex (2) has been substantiated by x‐ray crystallography. The catalytic protocol produces a diverse range of olefinated products up to 90% by employing readily available primary alcohols. The present synthetic strategy is operationally simple and scalable and tolerates various functional groups under mild reaction conditions. Notably, an aldehyde and aryl‐2‐quinoline‐2‐yl‐ethanol intermediate are involved in the catalytic reaction mechanism. The utility of the present procedure is demonstrated through a facile synthesis of the antifungal drug (E)‐2‐(2‐(pyridin‐4‐yl)vinyl)quinoline.