The commercially available and cheap Pd/C was found to promote Sonogashira couplings in the environmentally friendly choline chloride/glycerol eutectic mixture in the absence of external ligands. Under heterogeneous conditions, (hetero)aryl iodides were successfully coupled with both aromatic and aliphatic alkynes in yields ranging from 50 to 99 % within 3 h at 60 °C. The aforementioned catalytic system proved to be effective also towards electron‐rich iodides, which are notoriously known to be poorly reactive in Pd‐catalyzed Sonogashira coupling reactions. The eutectic mixture and the catalyst could easily and successfully be recycled up to four times with an E‐factor as low as 24.4.

A palladium-catalysed aminocarbonylation of (hetero)aryl iodides has, for the first time, been accomplished in deep eutectic solvents as environmentally benign and recyclable media, under mild conditions. The reactions proceeded with a good substrate scope, and a variety of amides have been synthesized in yields up to 98%.

A Deep Eutectic Solvent like choline chloride/glycerol (1:2 mol mol–1) proved to be an effective, sustainable reaction medium to easily synthesize both phenacyl azides and symmetrical 2,5‐diarylpyrazines of interest in pharmacology and in coordination chemistry. Notable features of our report include: (i) nucleophilic substitution reactions of α‐halo carbonyl compounds to the corresponding phenacyl azides compatible with the eutectic mixture, (ii) the reduction of phenacyl azides to α‐amino carbonyl compounds, which undergo spontaneous dimerisation/cyclisation/aromatisation in the same eutectic mixture to provide valuable pyrazines. Telescoped, one‐pot, two‐steps stoichiometric/catalytic processes have also been successfully developed to furnish 2,5‐diarylpyrazines in up to 95 % yield.

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