Alkene-promoted NHC ligand substitution in orthometalated Ru-NHC complexes σ-bond metathesis: a mechanistic insight.

Herein, we report an unprecedented NHC ligand substitution around a ruthenium center, exploiting an orthometalated complex. Captivatingly, the employed metal complex here undergoes a unique σ-bond metathesis in the presence of an alkene and azolium salt, leading to facile exchange of ancillary NHC ligands at the Ru-center, which is not known to the best of our knowledge.

(Benz)imidazo[1,2-a]quinolinium Salts: Access via Unprecedented Regiospecific non-AAIPEX Strategy and Study of Their Tunable Properties.

An unprecedented non-AAIPEX protocol has been developed to access diverse monosubstituted cationic polycyclic heteroaromatic compounds (cPHACs) from the readily available azolium salts and phenacyl bromides via Ru(II)-catalyzed tandem annulation cum aromatization. This atom-economic protocol executes a range of intermediate steps e. g.

Base-catalyzed Effective C2-Amidation of Azolium Salts Using Isocyanates under Mild Conditions.

An unprecedented base-catalyzed hydroarylation of isocyanates with azolium salts was developed, which follows a simple reaction pathway and provided facile access to diverse C2-amidated azolium salts under mild conditions. Importantly, this methodology can also be applied for the successive C2-amidation of a bisimidazolium salt with two different isocyanates to provide the corresponding unsymmetrically substituted bisamide derivatives. Notably, the obtained amidated salts can also serve as a prominent carbene surrogate for the synthesis of metal-NHC complexes.

Catalyst- and solvent-free efficient access to N-alkylated amines via reductive amination using HBpin.

A sustainable approach which works under catalyst- and solvent-free conditions for the synthesis of structurally diverse secondary amines has been uncovered. This one-pot protocol works efficiently at room temperature and is compatible with a wide range of sterically and electronically diverse aldehydes and primary amines. Notably, this simple process offers scalability, excellent functional group tolerance, chemoselectivity, and is also effective at the synthesis of biologically relevant molecules.