Developing more sustainable catalytic processes for preparing N-heterocyclic compounds in a less costly, compact, and greener manner from cheap and readily available reagents is highly desirable in modern synthetic chemistry. Herein, we report a straightforward synthesis of benzimidazoles by reductive coupling of o -dinitroarenes with aldehydes in the presence of molecular hydrogen. An innovative molecular cluster-based synthetic strategy that employs Mo 3 S 4 complexes as precursors have been used to engineer a sulfur-deficient molybdenum disulfide (MoS 2 )-type material displaying structural defects on both the naturally occurring edge positions and along the typically inactive basal planes. By applying this catalyst, a broad range of functionalized 2-substituted benzimidazoles, including bioactive compounds, can be selectively synthesized by such a direct hydrogenative coupling protocol even in the presence of hydrogenation-sensitive functional groups, such as double and triple carbon–carbon bonds, nitrile and ester groups, and halogens as well as diverse types of heteroarenes.

The tetrahydropyridine structure is present in a wide variety of natural and synthetic compounds with interesting pharmacological properties. Therefore, the search for new chemical routes capable of yielding this valuable nitrogen‐containing heterocycle is of utmost interest. Herein, we report the use of the ruthenium‐catalyzed ring‐closing enyne metathesis (RCEYM) and cross enyne metathesis/ring‐closing metathesis (CEYM/RCM) reactions of chiral nitrogen‐containing 1,7‐enynes as an efficient route to synthesize a variety of enantioenriched tetrahydropyridine‐based conjugated 1,3‐dienes. The RCEYM presented wide functional group tolerance and took place in moderate to high yields, with no significant differences when carried out on gram scale. These 1,3‐dienes were suitable for further transformations, such as the Diels–Alder reaction, effectively yielding more complex enantioenriched bicyclic structures.

Vinylogous Mukaiyama Mannich reactions of furan and pyrrole based dienoxy silanes with α‐fluoroalkyl sulfinyl imines provide a powerful synthetic access to a variety of amino fluoroalkyl γ‐butenolide‐type and butyrolactam frameworks with high regio‐ and diastereoselectivity. Anti‐configured adducts were obtained in all cases, independent of the nature of the heteroatom (O or N) present in the dienoxy silane. The absolute configuration of the adducts prepared was unequivocally established by X‐ray crystallographic analysis. It is noteworthy that the introduction of substituents at the γ‐position of the heterocyclic partner allows the generation of adducts bearing chiral quaternary centers.magnified image