Synthesis 2024; 56(21): 3297-3306
DOI: 10.1055/a-2235-1380
paper
Special Issue PSRC-10 (10th Pacific Symposium on Radical Chemistry)

Photocatalyzed C–F Bond Heteroarylation of Trifluoromethyl­arenes with Heteroarenes: Two Roles of Bu3SnI as Fluoride Ion Scavenger and Activator for Photocatalyst

Naoki Sugihara
a   Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
,
Masayuki Abe
a   Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
,
a   Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
b   Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI), Osaka University, Suita, Osaka 565-0871, Japan
,
Makoto Yasuda
a   Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
b   Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI), Osaka University, Suita, Osaka 565-0871, Japan
› Author Affiliations
This work was financially supported by the Japan Society for the Promotion of Science [JSPS KAKENHI JP23K17845 (M.Y.)]. This work was supported by the Grant-in-Aid for Transformative Research Areas (A) 21H05212 (M.Y.) Digitalization-driven Transformative Organic Synthesis (Digi-TOS) from the Ministry of Education, Culture, Sports, Science and Technology, Japan and JST CREST (Core Research for Evolutional Science and Technology) Grant No. JPMJCR20R3 (M.Y.), Japan. N.S. acknowledges support from the JSPS Fellowship for Young Scientists (22J10775). Y.N. acknowledges support from Research Encouragement Grants of The Asahi Glass Foundation.


Abstract

We report the C–F bond heteroarylation of trifluoromethylarenes with heteroarenes by using Ir(ppy)3 catalyst and Bu3SnI under visible-light irradiation. Various heteroarenes such as pyrrole, furan, and thiophene derivatives were applied to the present reaction. The present heteroarylation enables the transformation of various functionalized trifluoromethylarenes because of the mild reaction conditions. Notably, the late-stage transformation of a drug molecule, bicalutamide, was demonstrated. Mechanistic studies including a light on–off interval experiment, Stern–Volmer luminescence-quenching measurements, and DFT calculations clarified two critical roles of Bu3SnI for the successful progress of the heteroarylation. Bu3SnI functions as a fluoride ion scavenger to suppress the undesired C–F bond re-formation. Bu3SnI also acts as a single-electron source for the reduction of photoexcited Ir(ppy)3* to generate Ir(II) species to effectively reduce ArCF3.

Supporting Information



Publication History

Received: 28 November 2023

Accepted after revision: 22 December 2023

Accepted Manuscript online:
22 December 2023

Article published online:
29 January 2024

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