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![[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)
[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
ConPET-Driven Aryl Halide Reduction with a Donor-Acceptor-Donor Anion Radical
Abul Mansur Muhammed Fahim1, Habtom B Gobeze1, Kanyashree Jana1
1Department of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas78249, United States.
Abstract:
This study investigates the anion radical of a donor-acceptor-donor molecule, namely 4,7-di(thiophen-2-yl)benzo[c][1,2,5]thiadiazole (TBT), as a photosensitizer for consecutive photoinduced electron transfer (conPET) reactions. Fluorescence lifetime decay and femtosecond transient absorption spectroscopy on TBT-• revealed a doublet excited state lifetime of 250 ± 6 ps. Cyclic voltammetry and excited state energy (E00) analysis determined the excited state potential, E(TBT/*TBT-•) = -2.80 V vs SCE. Rehm-Weller analysis of the excited state (*TBT-•) quenching kinetics also corroborated the estimated excited state potential. Model reactions with a series of aryl bromides monitored by 19F-NMR and HPLC confirmed that TBT-• can act as a strongly reducing photosensitizer for visible light-mediated aryl halide reduction via a conPET mechanism.
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