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Updated: Oct 21, 2025
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Microwave-assisted Intramolecular Dehydrogenative Diels-Alder Reactions for the Synthesis of Functionalized Naphthalenes/Solvatochromic Dyes
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Towards new NIR dyes for free radical photopolymerization processes
Haifaa Mokbel1,2, Guillaume Noirbent3, Didier Gigmes3
1Université de Haute-Alsace, CNRS, IS2M UMR 7361, F-68100 Mulhouse, France.
Beilstein Journal of Organic Chemistry
|September 3, 2021
Summary
Researchers developed 17 novel near-infrared (NIR) dyes for photoinitiation. These cyanine-based dyes enable efficient polymerization and photothermal effects using NIR light, overcoming previous challenges.
Area of Science:
- Polymer Chemistry
- Photochemistry
- Materials Science
Background:
- Near-infrared (NIR) light offers safe and cost-effective photoinitiation but faces challenges due to low photon energy.
- Developing efficient photoinitiating systems for NIR light is crucial for advanced material synthesis.
Purpose of the Study:
- To design and synthesize novel NIR dyes based on a cyanine scaffold for photoinitiation applications.
- To evaluate the photoinitiating capabilities and photothermal effects of these new dyes.
Main Methods:
- Synthesis of 17 NIR dyes, including 11 novel compounds, based on a cyanine scaffold.
- Investigation of noncharged, negatively charged, and positively charged cyanine structures.
- Evaluation of photoinitiation efficiency with iodonium salt and amine, and assessment of photothermal effects.
Main Results:
- Several synthesized NIR dyes demonstrated excellent photoinitiating abilities.
- Significant photothermal effects were observed for various NIR dye structures.
- The developed systems facilitated the synthesis of interpenetrating polymer networks (IPNs) using NIR light.
Conclusions:
- The novel cyanine-based NIR dyes are effective photoinitiators for polymerization and exhibit useful photothermal properties.
- These findings expand the toolkit for NIR-initiated polymerization and material fabrication.
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