Related Experiment Video
Updated: Feb 3, 2026

Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols
Published on: April 4, 2014
Switching Copper(II)-Catalytic Process for the Selective Access to C3-Imidazolyl- and Pyridylquinoxalin-2(1H)-ones
S Banuprakash Goud1, Raju L Dhakar1, Sampak Samanta1
1Department of Chemistry, Indian Institute of Technology Indore, Simrol, Indore, Madhya Pradesh 453552, India.
Abstract:
A simple pseudofour-component reaction catalyzed by CuBr2 has been developed to deliver C3-imidazoylquinoxalinones with decent yields from quinoxalin-2(1H)-ones, acetophenones, and ammonium persulfate in DMSO. This process follows a sequence of cross-dehydrogenative coupling/Kornblum oxidation/aza-cyclization, creating selectively four new C-C, two C-N, and C═N bonds. Interestingly, the Kornblum oxidation step can be skipped by simply replacing CuBr2 with Cu(OAc)2. This alteration leads to high-value C3-pyridylquinoxalinones. Notably, DMSO serves both as a C-H source for pyridine ring synthesis and an effective solvent for this conversion. In addition, the acquired 3-imidazolyl- and pyridylquinoxalinones were transmuted into value-added 3-(imidazo[1,2-a]pyrazin-3-yl)quinoxalinone and 2-sulfonylquinoxalines, showcasing the synthetic utility of our method.
Related Concept Videos
Switching of BJT
Cut-off Mode ("Off" State): In this state, both the emitter-base and collector-base junctions are...
Turnover Number and Catalytic Efficiency
Chymotrypsin is a pancreatic enzyme that breaks down proteins during digestion....
Catalytically Perfect Enzymes
Most enzymes...
What is Natural Selection?
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

