Bora Kang, Marissa N. Lavagnino, Jesse B. Gordon, Kristopher G. Reynolds, Daniel G. Nocera, Alexander T. Radosevich
{"title":"Visible Light Promotes PIII/PV‑Catalyzed Reductive N‑Arylation of Nitroarenes at Room Temperature","authors":"Bora Kang, Marissa N. Lavagnino, Jesse B. Gordon, Kristopher G. Reynolds, Daniel G. Nocera, Alexander T. Radosevich","doi":"10.1021/acscatal.5c04341","DOIUrl":null,"url":null,"abstract":"Visible-light irradiation is found to accelerate the reductive coupling of nitroarenes and arylboronic acids under the conditions of P<sup>III</sup>/P<sup>V</sup> catalysis. Specifically, blue-light (λ<sub>exc</sub> = 427 nm) illumination of a catalytic mixture composed of a redox active main group catalyst (1,2,2,3,4,4-hexamethylphosphetane <italic toggle=\"yes\">P</italic>-oxide, i.e., <bold>P</bold>·[O]) and terminal reductant (1,3-diphenyldisiloxane) enables formation of diarylamines from nitroarenes and arylboronic acids at ambient temperature. In situ <sup>31</sup>P NMR data demonstrate the importance of fast in situ P<sup>V</sup>O → P<sup>III</sup> reduction by the hydrosilane reductant to permit productive room temperature reductive coupling. Moreover, the present photochemical method expands the scope of the organophosphorus-catalyzed reductive coupling reaction to accommodate 2,6-disubstituted nitroarenes, which were previously poorly reactive under prior thermal (dark) reaction conditions. Transient absorption experiments are consistent with excitation of the nitroarene to generate a triplet excited state, which is quenched by intermolecular electron transfer from the P<sup>III</sup> resting state of the catalyst with rate constants near the diffusion-controlled limit (<italic toggle=\"yes\">k</italic> <sub>q</sub> = 2.93 × 10<sup>9</sup> M<sup>–1</sup> s<sup>–1</sup>). These results establish the successful interface of a P<sup>III</sup>/P<sup>V</sup> catalytic cycle with photon input, suggesting additional opportunities for photodriven methods that exploit organophosphorus-based catalytic intermediates.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"96 1","pages":""},"PeriodicalIF":13.1000,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"ACS Catalysis ","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.1021/acscatal.5c04341","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
Visible-light irradiation is found to accelerate the reductive coupling of nitroarenes and arylboronic acids under the conditions of PIII/PV catalysis. Specifically, blue-light (λexc = 427 nm) illumination of a catalytic mixture composed of a redox active main group catalyst (1,2,2,3,4,4-hexamethylphosphetane P-oxide, i.e., P·[O]) and terminal reductant (1,3-diphenyldisiloxane) enables formation of diarylamines from nitroarenes and arylboronic acids at ambient temperature. In situ 31P NMR data demonstrate the importance of fast in situ PVO → PIII reduction by the hydrosilane reductant to permit productive room temperature reductive coupling. Moreover, the present photochemical method expands the scope of the organophosphorus-catalyzed reductive coupling reaction to accommodate 2,6-disubstituted nitroarenes, which were previously poorly reactive under prior thermal (dark) reaction conditions. Transient absorption experiments are consistent with excitation of the nitroarene to generate a triplet excited state, which is quenched by intermolecular electron transfer from the PIII resting state of the catalyst with rate constants near the diffusion-controlled limit (kq = 2.93 × 109 M–1 s–1). These results establish the successful interface of a PIII/PV catalytic cycle with photon input, suggesting additional opportunities for photodriven methods that exploit organophosphorus-based catalytic intermediates.
期刊介绍:
ACS Catalysis is an esteemed journal that publishes original research in the fields of heterogeneous catalysis, molecular catalysis, and biocatalysis. It offers broad coverage across diverse areas such as life sciences, organometallics and synthesis, photochemistry and electrochemistry, drug discovery and synthesis, materials science, environmental protection, polymer discovery and synthesis, and energy and fuels.
The scope of the journal is to showcase innovative work in various aspects of catalysis. This includes new reactions and novel synthetic approaches utilizing known catalysts, the discovery or modification of new catalysts, elucidation of catalytic mechanisms through cutting-edge investigations, practical enhancements of existing processes, as well as conceptual advances in the field. Contributions to ACS Catalysis can encompass both experimental and theoretical research focused on catalytic molecules, macromolecules, and materials that exhibit catalytic turnover.