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Abstract A new iodinated BODIPY dye incorporating a thioether‐ has been synthesized and characterized. The benzimidazole unit was introduced at themeso‐pentafluorophenyl position of the BODIPY scaffold via high‐yield click chemistry. This substitution does not alter the strong absorption and emission properties of the BODIPY chromophore and provides a versatile platform for the attachment of pharmacologically important molecules. Further functionalization of the BODIPY core with iodine at the 3‐ and 5‐positions yields a derivative capable of generating reactive oxygen species when irradiated with low energy light. Experimental evidence confirms the production of both singlet oxygen and superoxide radicals, indicating this complex is capable of operating by both Type I and Type II photosensitization pathways. This dual capacity could be responsible for its effectiveness as a photosensitizer and contribute to its photobiological activity against human melanoma cells.
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This content will become publicly available on April 1, 2027
Oxygen-tolerant green-light photopolymerizations with type I boron-alkylated BODIPYs: The power of a methylene
Not AvailableConventional type I photoinitiators require high-energy ultraviolet (UV) light to generate radicals, whereas most visible-light systems rely on slower, oxygen-sensitive type II photosensitization pathways. We report boron-alkylated boron-dipyrromethenes (BODIPYs) as type I photoinitiators that operate efficiently under green-light-emitting diodes (LEDs) and ambient conditions. Replacing methyl with ethyl at the boron site accelerates photolysis, lowers the B–C bond dissociation energy, and suppresses oxygen sensitization. Consequently, the ethyl derivative doubles the polymerization rate and decreases oxygen inhibition times by over an order of magnitude. Relative to Ivocerin, a leading blue-light type I photoinitiator, the BODIPY system achieves a higher external quantum yield due to stronger absorption. Owing to these performance enhancements, the ethyl derivative enables rapid, ambient, green-light digital light processing (DLP) 3D printing of commercial acrylate resins, achieving 2.5 s exposures per 50 µm layer at 3 mW cm^−2. This oxygen-tolerant platform provides a practical, mild route for photocurable technologies.
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- Award ID(s):
- 2403819
- PAR ID:
- 10697928
- Publisher / Repository:
- Cell Press
- Date Published:
- Journal Name:
- Chem
- ISSN:
- 2451-9294
- Page Range / eLocation ID:
- 103043
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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