here we took advantage of the photophysical properties of cercosporin, and used it as a metal-free photocatalyst to develop an unprecedented cercosporin-driven photocatalysis under mild conditions. Furthermore, the forming conditions and excited-state dynamics of radical anions of cercosporin have been systematically investigated. In particular, transient femtosecond absorption spectroscopy was employed
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
Direct Arylation of Pyrrole Derivatives in Ionic Liquids
作者:Olena Vakuliuk、Daniel T. Gryko
DOI:10.1002/ejoc.201100004
日期:2011.5
An efficient methodology for the directarylation of pyrrolederivatives has been developed. The reaction proceeds smoothly with a wide range of structurally diverse aryl iodides. Derivatives bearing an N,N-dimethylamino group at the 1-position and an aryl substituent at the 2-position were prepared for the first time. This protocol is more environmentally friendly than those previously reported because
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.
Direct Arylation of Pyrrole Derivatives in Superbasic Media
作者:Daniel Gryko、Olena Vakuliuk、Beata Koszarna
DOI:10.1055/s-0030-1260128
日期:2011.9
Direct arylation of N-alkyl- and N-arylpyrroles with aryl iodides can be performed in superbasic media, withoutexternal addition of a transition-metal catalyst. Lithium hydroxide in dimethyl sulfoxide promotes this reaction in a regioselective manner, leading to the expected 2-arylated products in good yield. pyrrole - heterocycles - C-C coupling - C-H activation - arylhalides