Related Experiment Video
Updated: Jun 21, 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 Organic Photosensitizers Based on 2-(2-Aminophenyl)benzothiazoles for Photocycloaddition Reactions
Ekaterina Pylova1,2,3, Benjamin Lasorne1, Nathan D McClenaghan4
1ICGM, Univ Montpellier, CNRS, ENSCM, 34090, Montpellier, France.
Abstract:
We have studied 2-(2-aminophenyl)benzothiazole and related derivatives for their photophysical properties in view of employing them as new and readily tunable organic photocatalysts. Their triplet energies were estimated by DFT calculations to be in the range of 52-57 kcal mol-1, suggesting their suitability for the [2+2] photocycloaddition of unsaturated acyl imidazoles with styrene derivatives. Experimental studies have shown that 2-(2-aminophenyl)benzothiazoles comprising alkylamino groups (NHMe, NHiPr) or the native amino group provide the best photocatalytic results in these visible-light mediated [2+2] reactions without the need of any additives, yielding a range of cyclobutane derivatives. A combined experimental and theoretical approach has provided insights into the underlying triplet-triplet energy transfer process.
Related Concept Videos
Cycloaddition Reactions: MO Requirements for Photochemical Activation
Cycloaddition Reactions: Overview
Cycloaddition Reactions: MO Requirements for Thermal Activation
Photochemical Electrocyclic Reactions: Stereochemistry
Selection Rules: Photochemical Activation
Nucleophilic Aromatic Substitution: Elimination–Addition
Aryldiazonium Salts to Azo Dyes: Diazo Coupling
![[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)
