Related Experiment Video
Updated: Jul 1, 2025
![Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60786.jpg&w=3840&q=50)
Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Visible light-induced organo-photocatalyzed route to synthesize substituted pyrazoles
Koustav Pal1, Vinjamuri Srinivasu1, Sourabh Biswas1
1Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal 741246, India. suresh@iiserkol.ac.in.
Abstract:
The synthesis of tetra-substituted pyrazoles holds significant synthetic value and has been accomplished through an organo-photocatalyzed decarboxylative intramolecular cyclization using readily available 1,2-diaza-1,3-dienes and α-ketoacids. This method allows for the systematic synthesis of substituted pyrazole derivatives. Notably, this approach is characterized by its metal-free and oxidant-free nature, offering distinct advantages such as short reaction times and exceptionally mild reaction conditions. The developed methodology enables the efficient construction of tetra-substituted pyrazoles, expanding the available chemical space for exploration and opening up potential applications in various scientific fields.
More Related Videos
Related Concept Videos
Cycloaddition Reactions: MO Requirements for Photochemical Activation
Photochemical Electrocyclic Reactions: Stereochemistry
Selection Rules: Photochemical Activation
Aryldiazonium Salts to Azo Dyes: Diazo Coupling
Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene
The Z-Scheme of Electron Transport in Photosynthesis
Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide

![[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)