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Synthesis and Characterization of Acridinium Dyes for Photoredox CatalysisThis project was supported by Award No. R01 GM098340 from the National Institute of General Medical Sciences and a Camille Dreyfus Teacher-Scholar Award (D.A.N.). L.W. was supported by the International Postdoctoral Exchange Fellowship Program. Photophysical measurements were performed in the UNC-ERFC Instrumentation Facility established by the UNC-EFRC (Center for Solar Fuels, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001011).
Received: 21 January 2019
Accepted after revision: 12 February 2019
12 March 2019 (online)
Photoredox catalysis is a rapidly evolving platform for synthetic methods development. The prominent use of acridinium salts as a sustainable option for photoredox catalysts has driven the development of more robust and synthetically useful versions based on this scaffold. However, more complicated syntheses, increased cost, and limited commercial availability have hindered the adoption of these catalysts by the greater synthetic community. By utilizing the direct conversion of a xanthylium salt into the corresponding acridinium as the key transformation, we present an efficient and scalable preparation of the most synthetically useful acridinium reported to date. This divergent strategy also enabled the preparation of a suite of novel acridinium dyes, allowing for a systematic investigation of substitution effects on their photophysical properties.
References and Notes
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