Polysulfide Anions as Visible Light Photoredox Catalysts for Aryl Cross-Couplings
作者:Haoyu Li、Xinxin Tang、Jia Hao Pang、Xiangyang Wu、Edwin K. L. Yeow、Jie Wu、Shunsuke Chiba
DOI:10.1021/jacs.0c11968
日期:2021.1.13
we disclose the use of polysulfide anions as visible light photoredox catalysts for aryl cross-coupling reactions. The reaction design enables single-electron reduction of aryl halides upon the photoexcitation of tetrasulfide dianions (S42-). The resulting aryl radicals are engaged in (hetero)biaryl cross-coupling, borylation, and hydrogenation in a redox catalytic regime involving S4• -/S42- and S3• -/S32-
Sensitization-Initiated Electron Transfer for Photoredox Catalysis
作者:Indrajit Ghosh、Rizwan S. Shaikh、Burkhard König
DOI:10.1002/anie.201703004
日期:2017.7.10
tasks of light energy collection and electron transfer (i.e., redox reactions) are assigned to two different molecules. Ru(bpy)3Cl2 absorbs the visiblelight and transfers the energy to polycyclic aromatic hydrocarbons that enable the redox reactions. This operationally simple sensitization‐initiated electron transfer enables the use of arenes that do not absorb visiblelight, such as anthracene or pyrene
We developed a facile photoinduced disproportionation approach to generate radical anions of pyrrole derivatives for the reduction of aryl halides, as well as the formation of desired heterocyclic product without the addition of any photocatalysts.
Dichromatic Photocatalytic Substitutions of Aryl Halides with a Small Organic Dye
作者:Michael Neumeier、Diego Sampedro、Michal Májek、Víctor A. de la Peña O'Shea、Axel Jacobi von Wangelin、Raúl Pérez-Ruiz
DOI:10.1002/chem.201705326
日期:2018.1.2
soluble organic dye. The ultimately formed excited radicalanion DCA.−* enables the reductive activation of various aryl bromides and chlorides under mild conditions and the application to hetero-biaryl cross-coupling and heteroatom functionalizations. Detailed spectroscopic and theoretical studies support the postulated dichromatic photocatalytic mechanism.
Zr-MOF-OH are utilized for photocatalytic arylhalide derivatizations. Phenoxy anions in binaphthol derivatives show high reducing capacity, remarkable activity, good selectivity and fair compatibility towards the activation of arylhalidesthrough a single-electron transfer process under white light irradiation and alkaline conditions. The generated aryl radicals could undergo biaryl cross-coupling