Related Experiment Video
Updated: Jun 10, 2025

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
Visible Light-Induced Regioselective E to Z Isomerization of Polarized 1,3-Dienes: Experimental and Theoretical
Jayanta Saha1,2, Soumadip Banerjee3, Sidhartha Malo1,2
1Organic and Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, Kolkata 700032, India.
Abstract:
The stereocontrol of E → Z isomerization on a (1E,3E)-diene, instead of a simple alkene, can be more challenging due to the increased number of isomerization possibilities. Herein, we report visible light-mediated regioselective (1E,3E → 1E,3Z) isomerization of (1E,3E)-diene. The reaction conditions are mild and easy to apply and can be applied to a wide range of substances, with an excellent yield and selectivity (90:10). It is evident from the crystal structures that the cause of regioselectivity for the isomerization of 1,3-diene may not be limited to 1,3-allylic strains; CH-π interaction may also play a vital role. Computational studies suggest that this regioselective photoisomerization is a thermodynamically feasible process and requires the accumulation of spin density on the modified double bond for the transformation to occur.
More Related Videos
06:46Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
12:51A 'Plug and Play' Method to Create Water-dispersible Nanoassemblies Containing an Amphiphilic Polymer, Organic Dyes and Upconverting Nanoparticles
Published on: November 14, 2015
Related Concept Videos
Photochemical Electrocyclic Reactions: Stereochemistry
Selection Rules: Photochemical Activation
E1 Reaction: Stereochemistry and Regiochemistry
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
E2 Reaction: Stereochemistry and Regiochemistry
When a substrate with two different β hydrogens undergoes an E2 elimination, the presence of a strong base can yield two regioisomeric alkenes. The more-substituted alkene is the major...
Regioselectivity of Electrophilic Additions-Peroxide Effect