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Updated: Oct 9, 2025

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch

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Published on: February 7, 2022

Reactivity and selectivity modulation within a molecular assembly: recent examples from photochemistry.

Yeshua Sempere¹, Martin Morgenstern¹, Thorsten Bach²

¹Department Chemie and Catalysis Research Center (CRC), Technische Universität München, 85747, Garching, Germany.

Photochemical & Photobiological Sciences : Official Journal of the European Photochemistry Association and the European Society for Photobiology

|December 16, 2021

Summary

Photochemical reactions offer powerful synthetic routes but often lack selectivity. Molecular assemblies driven by non-covalent interactions enhance stereo- and chemoselectivity in these organic transformations.

Keywords:

molecular assembly organic synthesis photochemistry supramolecular

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Area of Science:

Organic Chemistry
Photochemistry
Supramolecular Chemistry

Background:

Photochemical reactions are valuable tools in organic synthesis.
Controlling selectivity (stereo- and chemoselectivity) remains a challenge.
Molecular assemblies offer a strategy to improve selectivity.

Purpose of the Study:

To review recent examples of photochemical reactions.
To highlight how molecular assemblies dictate reaction outcomes.
To showcase selectivity control via non-covalent interactions.

Main Methods:

Formation of molecular assemblies between photosubstrates and host molecules.
Utilizing non-covalent weak interactions to drive assembly.
Analysis of photochemical reaction outcomes.

Main Results:

Demonstrated unique outcomes in photochemical reactions.
Showcased improved stereo- and chemoselectivity.
Highlighted the role of host-guest complexation.

Conclusions:

Molecular assemblies are key to controlling photochemical reactions.
Non-covalent interactions are crucial for achieving selectivity.
This approach expands the scope of synthetic photochemistry.