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Search for "photocatalysts" in Full Text gives 84 result(s) in Beilstein Journal of Organic Chemistry.
Organic synthesis using photoredox catalysis
Beilstein J. Org. Chem. 2014, 10, 1097–1098, doi:10.3762/bjoc.10.107
- synthesis, the principles of photoredox chemistry serve as guidelines, i.e., photoinduced electron transfer (PET) kinetics and thermodynamics as expressed in the Rehm–Weller and Marcus equations. For catalytic versions, the photoinduced redox processes require efficient and robust photocatalysts, and in
On the mechanism of photocatalytic reactions with eosin Y
Beilstein J. Org. Chem. 2014, 10, 981–989, doi:10.3762/bjoc.10.97
- photocatalysts [3][4][5][6][7][8], whereas much less attention has been directed at eosin Y-catalyzed reactions. The reductive quenching pathway of eosin Y, which operates in the photooxidation of isoquinolines [9], has been studied in a single report [22]. To the best of our knowledge, related data have not
- -driven reactions that lie beyond the focus of this study. Eosin Y (and many other organic photocatalysts) undergo rapid acid–base equilibria which significantly alter the photophysical properties. It is therefore of pivotal importance to ascertain the actual nature of the employed dye under the reaction
Visible light mediated intermolecular [3 + 2] annulation of cyclopropylanilines with alkynes
Beilstein J. Org. Chem. 2014, 10, 975–980, doi:10.3762/bjoc.10.96
- compounds [21][22][23][24][25][26]. Amines have been used as an electron donor to reduce the excited state of photocatalysts, while they are oxidized to amine radical cations. Our group and others have taken advantage of this facile redox process and developed a number of synthetic methods that harness the
Metal and metal-free photocatalysts: mechanistic approach and application as photoinitiators of photopolymerization
Beilstein J. Org. Chem. 2014, 10, 863–876, doi:10.3762/bjoc.10.83
- formerly: University of Haute Alsace/ENSCMu, 3 rue Alfred Werner, 68093 Mulhouse Cedex, France 10.3762/bjoc.10.83 Abstract In the present paper, the photoredox catalysis is presented as a unique approach in the field of photoinitiators of polymerization. The principal photocatalysts already reported as
- well as the typical oxidation and reduction agents used in both reductive or oxidative cycles are gathered. The chemical mechanisms associated with various systems are also given. As compared to classical iridium-based photocatalysts which are mainly active upon blue light irradiation, a new
The chemistry of amine radical cations produced by visible light photoredox catalysis
Beilstein J. Org. Chem. 2013, 9, 1977–2001, doi:10.3762/bjoc.9.234
- ). Therefore, a photocatalyst is often required to initialize electron-transfer reactions with amines. Some of the frequently used photocatalysts include ruthenium [24][25][26] and iridium [27][28] polypyridyl complexes as well as organic dyes [29][30] that are absorbed in the visible-light region. They all
New core-pyrene π structure organophotocatalysts usable as highly efficient photoinitiators
Beilstein J. Org. Chem. 2013, 9, 877–890, doi:10.3762/bjoc.9.101
- photocatalysts. Successful results in terms of rates of polymerization and final conversions were obtained. The strong MO coupling between the six different cores and the pyrene moiety was studied by DFT calculations. The different chemical intermediates are characterized by ESR and laser flash photolysis
- ; photocatalysts; photoinitiators; radical photopolymerization; Introduction Free radical sources are encountered in various areas such as organic chemistry, biochemistry and polymer chemistry. In the field of polymer photochemistry applied to photopolymerization reactions, they are referred to as photoinitiators
Flow photochemistry: Old light through new windows
Beilstein J. Org. Chem. 2012, 8, 2025–2052, doi:10.3762/bjoc.8.229
- been shown to be unsuccessful under batch conditions. Nevertheless, the low flow rates and low concentrations involved limited output to 2.4 µmol/h, leaving significant questions over its synthetic utility [48][49][50]. Other redox chemistry to be performed by using titanium dioxide photocatalysts
Microphotochemistry: 4,4'-Dimethoxybenzophenone mediated photodecarboxylation reactions involving phthalimides
Beilstein J. Org. Chem. 2011, 7, 1055–1063, doi:10.3762/bjoc.7.121
- light, its removal from the product remains challenging. Compared to their acetone-sensitized counterparts [27], however, selectivities and yields were reduced. We are therefore currently investigating water soluble or solid-supported photocatalysts that absorb in the UVA region. The results from this
Synthesis of rigidified flavin–guanidinium ion conjugates and investigation of their photocatalytic properties
Beilstein J. Org. Chem. 2009, 5, No. 26, doi:10.3762/bjoc.5.26
- bonding site for oxoanions or carbonyl groups [45][46][47][48][49]. The structure of the new flavins was determined in solid state and in solution and their photocatalytic properties were tested. Results and Discussion Synthesis The synthesis of the potential photocatalysts 1 and 2, consisting of the
- bonds [54][55][56][57][58] and in solution the flavin chromophore is expected to rotate freely around the C–C single bonds of the ethane linker. Photocatalytic reactions Compounds 1 and 2 were tested as photocatalysts in three different reactions and their performance was compared to tetraacetyl
- effectively transferred in 1 and 2 to the relative flavin–guanidinium ion orientation, which is due to the flexible ethane linker between imide and flavin. Derivatives with a more constrained conformation of the flavin chromophore and the substrate binding sites may lead to chemical photocatalysts with better
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