Related Experiment Video
Updated: Jul 23, 2025

Light-driven Enzymatic Decarboxylation
Published on: May 22, 2016
Visible-Light-Mediated TiO2-Catalyzed Aerobic Dehydrogenation of N-Heterocycles in Batch and Flow
Junghoon Noh1, Jun-Young Cho1, Mincheol Park2
1Department of Fundamental Pharmaceutical Science, Kyung Hee University, Seoul 02447, South Korea.
Abstract:
We report a simple and environmentally friendly method for synthesizing N-containing heterocycles via a visible-light-mediated aerobic dehydrogenation reaction. Using a nontoxic, stable, and inexpensive titanium dioxide catalyst, a variety of substituted quinoline, indole, quinoxaline, and 3,4-dihydroisoquinoline derivatives could be synthesized using the green oxidant molecular oxygen. Improved reactivity and scalability of this reaction were demonstrated by adapting the photochemical multiphasic reaction to a continuous flow system. To gain insight into the mechanism, we also conducted several mechanistic studies, including absorption analysis, light on-off testing, and NMR analysis. Especially, oxygen is reduced to hydrogen peroxide, and dimethyl sulfoxide is a critical scavenger of the oxidant byproduct for ensuring high yields.
More Related Videos
12:08Catalytic Reactions at Amine-Stabilized and Ligand-Free Platinum Nanoparticles Supported on Titania During Hydrogenation of Alkenes and Aldehydes
Published on: June 24, 2022
13:09Utilization of Stop-flow Micro-tubing Reactors for the Development of Organic Transformations
Published on: January 4, 2018
Related Concept Videos
Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
Reduction of Alkenes: Catalytic Hydrogenation
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
Reduction of Benzene to Cyclohexane: Catalytic Hydrogenation
Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Phase I Oxidative Reactions: Overview
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...