Related Experiment Video
Updated: Aug 29, 2026

Time-resolved Photophysical Characterization of Triplet-harvesting Organic Compounds at an Oxygen-free Environment Using an iCCD Camera
Published on: December 27, 2018
Photochromism of triangle terthiophene derivatives as molecular re-router
Tsuyoshi Kawai1, Taisuke Iseda, Masahiro Irie
1Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Hakozaki 6-10-1, Higashi-ku, Fukuoka 812-8581, Japan. tkawai@cstf.kyushu-u.ac.jp
Abstract:
2,2[prime or minute]-3,3[double prime]-Terthiophene derivatives undergo photochemically reversible cyclization and cycloreversion reactions. The absorption peak wavelength changed systematically with substitution of the phenyl rings at 5-, 5[prime or minute]- and 5[double prime]-positions of the thiophene rings, which indicates re-routing of the [small pi]-conjugation system.
Related Concept Videos
Thermal and Photochemical Electrocyclic Reactions: Overview
Photochemical Electrocyclic Reactions: Stereochemistry
Selection Rules: Photochemical Activation
Woodward–Hoffmann Selection Rules and Microscopic Reversibility
Thermal Electrocyclic Reactions: Stereochemistry
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Cycloaddition Reactions: MO Requirements for Photochemical Activation
Thermal Sigmatropic Reactions: Overview
Sigmatropic shifts are classified based on an order term [i, j ], where i and j indicate the number of atoms across which each end of the σ bond migrates. Below are examples of a [3,3] sigmatropic shift in 1,5-hexadiene, referred to as...
![[(DPEPhos)(bcp)Cu]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)