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Synthesis of oxalamides by acceptorless dehydrogenative coupling of ethylene glycol and amines and the reverse hydrogenation catalyzed by ruthenium.

ABSTRACT: A sustainable, new synthesis of oxalamides, by acceptorless dehydrogenative coupling of ethylene glycol with amines, generating H₂, homogeneously catalyzed by a ruthenium pincer complex, is presented. The reverse hydrogenation reaction is also accomplished using the same catalyst. A plausible reaction mechanism is proposed based on stoichiometric reactions, NMR studies, X-ray crystallography as well as observation of plausible intermediates.

SUBMITTER: Zou YQ

PROVIDER: S-EPMC8159388 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Acceptorless Dehydrogenative Coupling Using Ammonia: Direct Synthesis of N-Heteroaromatics from Diols Catalyzed by Ruthenium.

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Mechanistic Investigations of Ruthenium Catalyzed Dehydrogenative Thioester Synthesis and Thioester Hydrogenation.

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Facile synthesis of amides via acceptorless dehydrogenative coupling of aryl epoxides and amines† † Electronic supplementary information (ESI) available. See https://doi.org/10.1039/d2sc01959k

Project description:The synthesis of amides is significant in a wide variety of academic and industrial fields. We report here a new reaction, namely acceptorless dehydrogenative coupling of epoxides and amines to form amides catalyzed by ruthenium pincer complexes. Various aryl epoxides and amines smoothly convert into the desired amides in high yields with the generation of H2 gas as the only byproduct. Control experiments indicate that amides are generated kinetically faster than side products, possibly because of the facile activation of epoxides by metal–ligand cooperation, as supported by the observation of a ruthenium-enolate species. No alcohol or free aldehyde are involved. A mechanism is proposed involving a dual role of the catalyst, which is responsible for the high yield and selectivity of the new reaction. We report the ruthenium pincer complex catalyzed acceptorless dehydrogenative coupling of epoxides and amines to form amides. The reaction offers a facile and atom economical two-step strategy for transforming alkenes into amides.

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