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Abstract Next generation chemiluminescent iridium 1,2‐dioxetane complexes have been developed which consist of the Schaap's 1,2‐dioxetane scaffold directly attached to the metal center. This was achieved by synthetically modifying the scaffold precursor with a phenylpyridine moiety, which can act as a ligand. Reaction of this scaffold ligand with the iridium dimer [Ir(BTP)2(μ‐Cl)]2(BTP=2‐(benzo[b]thiophen‐2‐yl)pyridine) yielded isomers which depict ligation through either the cyclometalating carbon or, interestingly, the sulfur atom of one BTP ligand. Their corresponding 1,2‐dioxetanes display chemiluminescent responses in buffered solutions, exhibiting a single, red‐shifted peak at 600 nm. This triplet emission was effectively quenched by oxygen, yielding in vitro Stern‐Volmer constants of 0.1 and 0.009 mbar−1for the carbon‐bound and sulfur compound, respectively. Lastly, the sulfur‐bound dioxetane was further utilized for oxygen sensing in muscle tissue of living mice and xenograft models of tumor hypoxia, depicting the ability of the probe chemiluminescence to penetrate biological tissue (total flux ∼106 p/s).
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A versatile strategy for the formation of hydride-bridged actinide–iridium multimetallics
Uranium- and thorium-iridium multimetallic species with unprecedented actinide–iridium interactions are preparedviasalt-elimination reactions between U/Th halides and K[IrCp*H3].
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- Award ID(s):
- 2018784
- PAR ID:
- 10478469
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Chemical Science
- Volume:
- 14
- Issue:
- 4
- ISSN:
- 2041-6520
- Page Range / eLocation ID:
- 861 to 868
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d2sc04903a
