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Despite the inherent stability-enhancing benefits of dπ–pπ conjugation-induced aromaticity, metallaaromatic catalysts remain underutilized in this context, despite their reactivity with organic functionalities in stoichiometric reactions. We present a strategy for synthesizing a diverse range of iridaheteroaromatics, (L^L)IrIII(Cp*)I, including iridapyridylidene-indole, iridapyridene-indole, and iridaimidazole, via in situ deprotonation/metalation reactions utilizing [Cp*IrCl2]2and the respective ligands. These catalysts exhibit enhanced σ-donor and π-acceptor properties, intrinsic σ–π continuum attributes, and versatile binding sites, contributing to stability through enhanced dπ–pπ conjugation-induced aromaticity. Spectroscopic data, X-ray crystallographic data, and density functional theory calculations confirm their aromaticity. These iridaheteroaromatics exhibit formidable catalytic ability across a spectrum of transformations under industrially viable conditions, notably excelling in highly selective cross alkylation and β-alkylation of alcohols and an eco-friendly avenue for quinolone synthesis, achieving remarkably high turnover frequencies (TOFs). Additionally, this method extends to the self-condensation of bioalcohols like ethanol, n-butanol, and n-hexanol in water, replicating conditions frequently encountered in primary fermentation solutions. These iridaheteroaromatics exhibit strong catalytic activity with fast reaction rates, high TOFs, broad substrate compatibility, and remarkable selectivity, displaying their potential as robust catalysts in large-scale applications and emphasizing their practical significance beyond their structural and theoretical importance.

A versatile, selective, solvent (methanol vsethanol)- and base (potassium vslithium carbonate)-assisted switchable synthesis of saturated ketone and α-methyl saturated ketone from α,β-unsaturated ketone is developed. Mechanistic aspects, evaluated from spectroscopic studies, in situmonitoring of the reaction progress, control studies, and labeling studies, further indicate the involvement of a tandem dehydrogenation–condensation–hydrogenation sequence in the reaction, in which the interconvertible coordination mode (imino N → Ru and amido N–Ru) of coordinated imidazole with Ru(II)–para-cymene is crucial, without which the efficiency and selectivity of the catalyst are completely lost. The catalyst demonstrates good efficiency, selectivity, and functional group tolerance and displays a broad scope (69 examples) for monomethylation and hydrogenation of unsaturated chalcones, double methylation of ketones, and N-methylation of amines.