Rational perturbation of the fluorescence quantum yield in emission-tunable and predictable fluorophores (Seoul-Fluors) by a facile synthetic method involving C-H activation.
Fluorescence imaging enables the uniquely sensitive observation of functional- and molecular-recognition events in living cells. However, only a limited range of biological processes have been subjected to imaging because of the lack of a design strategy and difficulties in the synthesis of biosensors. Herein, we report a facile synthesis of emission-tunable and predictable Seoul-Fluors, 9-aryl-1,2-dihydrolopyrrolo[3,4-b]indolizin-3-ones, with various R(1) and R(2) substituents by coinage-metal-catalyzed intramolecular 1,3-dipolar cycloaddition and subsequent palladium-mediated CH activation. We also showed that the quantum yields of Seoul-Fluors are controlled by the electronic nature of the substituents, which influences the extent of photoinduced electron transfer. On the basis of this understanding, we demonstrated our design strategy by the development of a Seoul-Fluor-based chemosensor 20 for reactive oxygen species that was not accessible by a previous synthetic route.
Department of Chemistry/Bio-MAX Institute, Seoul National University, Seoul 151-747 (Korea).
Eun Joung
EJ
Choi
Eunha
E
Kim
Youngjun
Y
Lee
Ala
A
Jo
Seung Bum
SB
Park
D002244:Carbon / Q000737:chemistry; D002384:Catalysis; D061565:Cycloaddition Reaction; D004579:Electron Transport; D005456:Fluorescent Dyes / Q000138:chemical synthesis* / Q000737:chemistry; D006576:Heterocyclic Compounds, 4 or More Rings / Q000138:chemical synthesis* / Q000737:chemistry; D006859:Hydrogen / Q000737:chemistry; D010165:Palladium / Q000737:chemistry; D011758:Pyrroles / Q000138:chemical synthesis* / Q000737:chemistry; D011789:Quantum Theory; D017382:Reactive Oxygen Species / Q000737:chemistry
D005456:Fluorescent Dyes; D006576:Heterocyclic Compounds, 4 or More Rings; D011758:Pyrroles; D017382:Reactive Oxygen Species; D010165:Palladium; D002244:Carbon; D006859:Hydrogen; C042028:pyrroloindolizine
CH activation; fluorescence; fluorophore design; quantum yield; switchable sensors