6013-47-4Relevant articles and documents
Dimsyl Anion Enables Visible-Light-Promoted Charge Transfer in Cross-Coupling Reactions of Aryl Halides
Pan, Lei,Cooke, Maria Victoria,Spencer, Amara,Laulhé, Sébastien
, p. 420 - 425 (2021/11/01)
A methodology is reported for visible-light-promoted synthesis of unsymmetrical chalcogenides enabled by dimsyl anion in the absence of transition-metals or photoredox catalysts. The cross-coupling reaction between aryl halides and diaryl dichalcogenides proceeds with electron-rich, electron-poor, and heteroaromatic moieties. Mechanistic investigations using UV-Vis spectroscopy, time-dependent density functional theory (TD-DFT) calculations, and control reactions suggest that dimsyl anion forms an electron-donor-acceptor (EDA) complex capable of absorbing blue light, leading to a charge transfer responsible for generation of aryl radicals from aryl halides. This previously unreported mechanistic pathway may be applied to other light-induced transformations performed in DMSO in the presence of bases and aryl halides.
Regioselective C-H Thioarylation of Electron-Rich Arenes by Iron(III) Triflimide Catalysis
Dodds, Amy C.,Sutherland, Andrew
, p. 5922 - 5932 (2021/05/04)
A mild and regioselective method for the preparation of unsymmetrical biaryl sulfides using iron(III) catalysis is described. Activation of N-(arylthio)succinimides using the powerful Lewis acid iron(III) triflimide allowed the efficient thiolation of a range of arenes, including anisoles, phenols, acetanilides, and N-heterocycles. The method was applicable for the late-stage thiolation of tyrosine and tryptophan derivatives and was used as the key step for the synthesis of pharmaceutically relevant biaryl sulfur-containing compounds such as the antibiotic dapsone and the antidepressant vortioxetine. Kinetic studies revealed that while N-(arylthio)succinimides bearing electron-deficient arenes underwent thioarylation catalyzed entirely by iron(III) triflimide, N-(arylthio)succinimides with electron-rich arenes displayed an autocatalytic mechanism promoted by the Lewis basic product.
A Visible-Light-Harvesting Covalent Organic Framework Bearing Single Nickel Sites as a Highly Efficient Sulfur–Carbon Cross-Coupling Dual Catalyst
Chen, Hui,Liu, Wanlu,Laemont, Andreas,Krishnaraj, Chidharth,Feng, Xiao,Rohman, Fadli,Meledina, Maria,Zhang, Qiqi,Van Deun, Rik,Leus, Karen,Van Der Voort, Pascal
supporting information, p. 10820 - 10827 (2021/04/09)
Covalent Organic Frameworks (COFs) have recently emerged as light-harvesting devices, as well as elegant heterogeneous catalysts. The combination of these two properties into a dual catalyst has not yet been explored. We report a new photosensitive triazine-based COF, decorated with single Ni sites to form a dual catalyst. This crystalline and highly porous catalyst shows excellent catalytic performance in the visible-light-driven catalytic sulfur–carbon cross-coupling reaction. Incorporation of single transition metal sites in a photosensitive COF scaffold with two-component synergistic catalyst in organic transformation is demonstrated for the first time.