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A highly regioselective addition-elimination of Morita-Baylis-Hillman adducts promoted by base ionic liquids (0.5 mol%) was reported to afford a variety of functional alkenes in excellent yields (up to 99%). This protocol provides a new method to access functional alkenes directly. Recycled base ionic liquids could be reused at least five times and the isolated yield of the product was almost consistent after five runs. Key words: Morita-Baylis-Hillman adducts, functional ionic liquids, addition-elimination, regioselective. Nous faisons etat d'une reaction d'addition-elimination hautement regioselective menee sur des adduits de MoritaBaylis-Hillman, catalysee par des liquides ioniques (0,5 mol%) employes comme base et ayant produit une diversite d'alcenes fonctionnels dans d'excellents rendements (jusqu'a 99%). Le present protocole offre une nouvelle methode permettant d'acceder directement aux alcenes fonctionnels. En outre, les liquides ioniques employes comme bases recyclables peuvent etre reutilisees au moins cinq fois; les rendements des produits isoles etant demeures presque constants apres cinq cycles. [Traduit par la Redaction] Mots-cles: adduits de Morita-Baylis-Hillman, liquides ioniques fonctionnels, addition-elimination, regioselective., Introduction Functional alkene-containing compounds widely exist in natural products and pharmaceuticals of biological activities. (1) Regioselective addition-elimination of Morita-Baylis-Hillman (MBH) adducts is one of the most efficient methods for functional [...]

CoFe2O4 nanoparticles were uniformly anchored on reduced graphene oxide by a facile solvothermal method. The obtained CoFe2O4/reduced graphene oxide (CoFe2O4/rGO) hybrid was employed as catalyst for Li–O2 batteries. It could effectively lower the ORR (oxygen reduction reaction) and OER (oxygen evolution reaction) overpotentials of the batteries and deliver a large capacity of 12 235 mA h grGO−1 (2116 mA h ghybrid−1). It also exhibited high cyclic stability. [ABSTRACT FROM AUTHOR]

Pyridine, a widespread aromatic heterocycle, features a sp 2 -hybridized nitrogen atom that can readily coordinate to metals, leading to distinctive achievements in catalysis. In stark contrast, π-coordination of pyridine and derivatives with transition metals is notably scarce, and the involvement of such activation mode in catalysis remains to be developed. Herein, we present amination reactions of aminopyridines that leverages the reversible π coordination with a ruthenium catalyst as the arenophilic π acid, rather than relying on the conventional κ-N coordination. Specifically, a transient η 6 -pyridine complex functions as the electrophile in the nucleophilic aromatic substitution with amines, providing a diverse array of products via the cleavage of the pyridyl C-N bond. In addition, this method can be employed to incorporate chiral amines and 15 N-labeled amines.

The increasing pharmaceutical importance of trifluoromethylarenes has stimulated the development of more efficient trifluoromethylation reactions. Tremendous efforts have focused on copper- and palladium-mediated/catalyzed trifluoromethylation of aryl halides. In contrast, no general method exists for the conversion of widely available inert electrophiles, such as phenol derivatives, into the corresponding trifluoromethylated arenes. Reported herein is a practical nickel-mediated trifluoromethylation of phenol derivatives with readily available trimethyl(trifluoromethyl)silane (TMSCF 3 ). The strategy relies on PMe 3 -promoted oxidative addition and transmetalation, and CCl 3 CN-induced reductive elimination. The broad utility of this transformation has been demonstrated through the direct incorporation of trifluoromethyl into aromatic and heteroaromatic systems, including biorelevant compounds., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)