In the last few years, imidazo[1,5-a]pyridine scaffolds and derivatives have attracted growing attention due to their unique chemical structure optical behaviors. this work, a series of pyridylimidazo[1,5-a]pyridine corresponding pyridinium salts were synthesized properties investigated evaluate effect quaternization on features both in solution polymeric matrix. A critical analysis based spect...

Chitosan, a natural polysaccharide, has been widely used as biomaterial, especially for hemostasis. However, hemostatic materials processed from pure chitosan have limited effect and are extremely unstable in some cases; chemical modification is therefore needed to improve the properties of chitosan. Through reactions with hydroxyl amino groups macromolecules, such alkylation, carboxylation, qu...

A wide variety of quaternary ammonium compounds (QACs) have escalated the attraction researchers to explore application QACs. The frequently been synthesized through alkylation or quaternization tertiary amines with alkyl halides. Recently, QACs applied compatibilize polymer blends and composites in improving their thermo-mechanical properties. This concise review concentrates on two types as c...

The photooxidation of thebaine (3) with a sun lamp affords two main products: hydrodibenzofuran 10 (major) and benzofuran 11 (minor). The latter compound becomes predominant if a Hg lamp is used instead of a sun lamp. The formation of 10 proceeds via an endoperoxide intermediate that undergoes oxidation at the nitrogen atom. Protection of the nitrogen either by protonation or quaternization pre...

Quaternary salts of pyridoxal oxime have been synthesized by the quaternization of pyridoxal oxime with substituted phenacyl bromides using microwave heating. Microwave-assisted rapid synthesis was done both in solvent (acetone) and under solvent-free conditions. Good to excellent yields (58%-94%) were obtained in acetone in very short reaction times (3-5 min) as well as in the solvent-free pro...

Transmetalation is a key elementary reaction of many important catalytic reactions. Among these, 1,4-addition of arylboronic acids to organic acceptors such as α,β-unsaturated ketones has emerged as one of the most important methods for asymmetric C-C bond formation. A key intermediate for the B-to-Rh transfer arising from quaternization on a boronic acid by a Rh-bound hydroxide (the active cat...