Facile synthesis of amides acceptorless dehydrogenative coupling of aryl epoxides and amines.

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 H gas as the only byproduct.

Acceptorless dehydrogenative synthesis of primary amides from alcohols and ammonia.

The highly desirable synthesis of the widely-used primary amides directly from alcohols and ammonia acceptorless dehydrogenative coupling represents a clean, atom-economical, sustainable process. Nevertheless, such a reaction has not been previously reported, and the existing catalytic systems instead generate other N-containing products, , amines, imines and nitriles. Herein, we demonstrate an efficient and selective ruthenium-catalyzed synthesis of primary amides from alcohols and ammonia gas, accompanied by H liberation.

Dehydrogenative ester synthesis from enol ethers and water with a ruthenium complex catalyzing two reactions in synergy.

We report the dehydrogenative synthesis of esters from enol ethers using water as the formal oxidant, catalyzed by a newly developed ruthenium acridine-based PNP(Ph)-type complex. Mechanistic experiments and density functional theory (DFT) studies suggest that an inner-sphere stepwise coupled reaction pathway is operational instead of a more intuitive outer-sphere tandem hydration-dehydrogenation pathway.

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

A sustainable, new synthesis of oxalamides, by acceptorless dehydrogenative coupling of ethylene glycol with amines, generating H, 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.