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Integrating a Triplet-triplet Annihilation Up-conversion System to Enhance Dye-sensitized Solar Cell Response to Sub-bandgap Light
Published on: September 12, 2014
Photocyclization by a triplet-triplet annihilation upconversion pair in water - avoiding UV-light and oxygen removal
R Jeyaseelan1, M Utikal1, C G Daniliuc1
1Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut Corrensstraße 40 48149 Münster Germany lnaesbor@uni-muenster.de.
Abstract:
We present a formal [2 + 2]-cycloaddition of unsaturated ketones enabled by a green-to-ultraviolet triplet-triplet annihilation upconversion (TTA-UC) pair, using commercially available Ru(bpy)32+ and pyrene as sensitizer and annihilator, respectively. In the developed protocol, visible light irradiation at λmax = 520 nm allows for the reaction to proceed without the need for UV-light and the aqueous medium eliminates the need for oxygen removing protocols. Through this study, the application of the readily available upconversion pair is broadened to include cyclization reactions. We showcase the utility of the system by generating bicyclo[2.1.1]hexanes that are valuable bioisosteres of ortho-substituted benzenes, a promising motif for pharmaceuticals.
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