A molecular boron cluster-based chromophore with dual emission
Bromination of the luminescent borane, anti -B 18 H 22 , via electrophilic substitution using AlCl 3 and Br 2 , yields the monosubstituted derivative 4-Br- anti -B 18 H 21 as an air-stable crystalline solid. In contrast to the unsubstituted parent compound, 4-Br- anti -B 18 H 21 possesses dual emission upon excitation with UV light and exhibits fluorescence at 410 nm and phosphorescence at 503 nm, with Φ total = 0.07 in oxygen-free cyclohexane. Increased oxygen content in cyclohexane solution quenches the phosphorescence signal. The fluorescent signal intensity remains unaffected by oxygen, suggesting that this molecule could be used as a ratiometric oxygen probe.
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- Award ID(s):
- 1846849
- PAR ID:
- 10220055
- Date Published:
- Journal Name:
- Dalton Transactions
- Volume:
- 49
- Issue:
- 45
- ISSN:
- 1477-9226
- Page Range / eLocation ID:
- 16245 to 16251
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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