The unusual nonbifunctional outer-sphere strategy was successfully utilized in developing an easily accessible N-heterocyclic carbene manganese (NHC-Mn) system for highly active α-alkylation of ketones with alcohols. This system was efficient for a wide range of ketones and alcohols under mild reaction conditions, and also for the green synthesis of quinoline derivatives. The direct outer-sphere mechanism and the high activity of the present system demonstrate the potential of nonbifunctional outer-sphere strategy in catalyst design for acceptorless dehydrogenative transformations.

A sustainable and green route to access diverse functionalized ketones via dehydrogenative–dehydrative cross‐coupling of primary and secondary alcohols is demonstrated. This borrowing hydrogen approach employing a pincer N‐heterocyclic carbene Mn complex displays high activity and selectivity. A variety of primary and secondary alcohols are well tolerant and result in satisfactory isolated yields. Mechanistic studies suggest that this reaction proceeds via a direct outer‐sphere mechanism and the dehydrogenation of the secondary alcohol substrates plays a vital role in the rate‐limiting step.

An example of homogeneous Mo-catalyzed direct N-alkylation of anilines or nitroarenes with alcohols is presented. The DFT aimed design suggested the easily accessible bis-NHC-Mo(0) complex features a strong hydride-donating ability, achieving effective N-alkylation of anilines or challenging nitroarenes with alcohols. The enhanced hydride-donating strategy should be useful in designing highly active systems for borrowing hydrogen transformations.

Incorporation of nitrile groups into fine chemicals is of particular interest through C(sp3)–H bonds activation of alkyl nitriles in the synthetic chemistry due to the highly efficient atom economy. However, the direct α-functionalization of alkyl nitriles is usually limited to its enolate chemistry. Here we report an electro-oxidative C(sp3)–H bond functionalization of acetonitrile with aromatic/aliphatic mercaptans for the synthesis of sulfur-containing β-enaminonitrile derivatives. These tetrasubstituted olefin products are stereoselectively synthesized and the stereoselectivity is enhanced in the presence of a phosphine oxide catalyst. With iodide as a redox catalyst, activation of C(sp3)–H bond to produce cyanomethyl radicals proceeds smoothly at a decreased anodic potential, and thus highly chemoselective formation of C–S bonds and enamines is achieved. Importantly, the process is carried out at ambient temperature and can be easily scaled up.

The implementation of non‐noble metals mediated chemistry is a major goal in homogeneous catalysis. Borrowing hydrogen/hydrogen autotransfer (BH/HA) reaction, as a straightforward and sustainable synthetic method, has attracted considerable attention in the development of non‐noble metal catalysts. Herein, we report a tungsten‐catalyzed N‐alkylation reaction of anilines with primary alcohols via BH/HA. This phosphine‐free W(phen)(CO)4 (phen=1,10‐phenthroline) system was demonstrated as a practical and easily accessible in‐situ catalysis for a broad range of amines and alcohols (up to 49 examples, including 16 previously undisclosed products). Notably, this tungsten system can tolerate numerous functional groups, especially the challenging substrates with sterically hindered substituents, or heteroatoms. Mechanistic insights based on experimental and computational studies are also provided.

A Rh(iii)-catalyzed regioselective intermolecular carbenoid insertion into the N-methylene Csp3–H bond has been achieved via an outer-sphere pathway.

Borrowing hydrogen N-alkylation is one of the most valuable transformations in organic synthesis with high selectivity and atomic economy. The general non-noble metal catalysts for borrowing hydrogen usually have limitations...

A series of d6 non-noble transition metal complexes are designed and studied computationally for the hydrogenation of CO2 to formic acid. Catalysts with a metal of weaker electronegativity and lower...