3393-77-9Relevant academic research and scientific papers
Proton-Activated “Off–On” Room-Temperature Phosphorescence from Purely Organic Thioethers
Huang, Linkun,Chen, Biao,Zhang, Xuepeng,Trindle, Carl O.,Liao, Fan,Wang, Yucai,Miao, Hui,Luo, Yi,Zhang, Guoqing
, p. 16046 - 16050 (2018)
Room-temperature phosphorescence (RTP)-based sensors have distinctive advantages over the fluorescence counterparts, such as larger Stokes shifts and longer lifetimes. Unfortunately, almost all RTP sensors are operated on quenching-based mechanisms given the sensitive nature of the emissive triplet state. Here we report a type of thioether RTP molecules that shows RTP “turn-on” when volatile acid vapors such as HCl are in contact. To elucidate the underlying mechanism, model thioethers containing different donor/acceptor combinations are investigated via fluorescence spectroscopy and theoretical calculations aided by molecular coordinates obtained from single-crystal X-ray diffraction. It is revealed that a charge-transfer character in the phosphorescence state is crucial. The “turn-on” design concept may significantly broaden the sensing application scope for organic RTP molecules.
Preparation of Recyclable and Versatile Porous Poly(aryl thioether)s by Reversible Pd-Catalyzed C–S/C–S Metathesis
Morandi, Bill,Rivero-Crespo, Miguel A.,Toupalas, Georgios
supporting information, p. 21331 - 21339 (2021/12/17)
Porous organic materials (polymers and COFs) have shown a number of promising properties; however, the lability of their linkages often limits their robustness and can hamper downstream industrial application. Inspired by the outstanding chemical, mechanical, and thermal resistance of the 1D polymer poly(phenylene sulfide) (PPS), we have designed a new family of porous poly(aryl thioether)s, synthesized via a mild Pd-catalyzed C–S/C–S metathesis-based method, that merges the attractive features common to porous polymers and PPS in a single material. In addition, the method is highly modular, allowing to easily introduce application-oriented functionalities in the materials for a series of environmentally relevant applications including metal capture, metal sensing, and heterogeneous catalysis. Moreover, despite their extreme chemical resistance, the polymers can be easily recycled to recover the original monomers, offering an attractive perspective for their sustainable use. In a broader context, these results clearly demonstrate the untapped potential of emerging single-bond metathesis reactions in the preparation of new, recyclable materials.
Palladium-catalysed thioetherification of aryl and alkenyl iodides using 1,3,5-trithiane as sulfur source
Kollár, László,Pongrácz, Péter,Rajat Rao, Yalamarti Venkat,Zugó, Alexandra
, (2021/12/17)
Thioetherification reaction of aryl iodides catalysed by palladium(II) complexes in the presence of 1,3,5-trithiane as sulphur source is reported. The paper presents the first homogeneous catalytic application of 1,3,5-trithiane in synthesis. Detailed optimization steps, the frames of the novel reaction are described, as well as the limitations and the substrate scope are also demonstrated. Moderate to good thioether yields were achieved in the presence of various substituted iodobenzenes and some alkenyl iodides, using palladium-xantphos catalyst system. Competitive reactions in the presence of mixed substrates were also performed and mechanistic considerations were assumed.
Scalable electrochemical reduction of sulfoxides to sulfides
Kong, Zhenshuo,Pan, Chao,Li, Ming,Wen, Lirong,Guo, Weisi
supporting information, p. 2773 - 2777 (2021/04/21)
A scalable reduction of sulfoxides to sulfides in a sustainable way remains an unmet challenge. This report discloses an electrochemical reduction of sulfoxides on a large scale (>10 g) under mild reaction conditions. Sulfoxides are activated using a substoichiometric amount of the Lewis acid AlCl3, which could be regeneratedviaa combination of inexpensive aluminum anode with chloride anion. This deoxygenation process features a broad substrate scope, including acid-labile substrates and drug molecules.
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.
Coupling of thiols and aromatic halides promoted by diboron derived super electron donors
Franco, Mario,Vargas, Emily L.,Tortosa, Mariola,Cid
supporting information, p. 11653 - 11656 (2021/11/12)
We have proven that pyridine-boryl complexes can be used as superelectron donors to promote the coupling of thiols and aromatic halides through a SRN1 mechanism. The reaction is efficient for a broad substrate scope, tolerating heterocycles including pyridines, enolizable or reducible functional groups. The method has been applied to intermediates in drug synthesis as well as interesting functionalized polythioethers through a controlled and consecutive intramolecular electron transfer process.
NiNP@rGO Nanocomposites as Heterogeneous Catalysts for Thiocarboxylation Cross-Coupling Reactions
Bandini, Marco,Bertuzzi, Giulio,Gazzano, Massimo,Kovtun, Alessandro,Lombardi, Lorenzo,Mazzaro, Raffaello,Morandi, Vittorio
supporting information, (2021/12/17)
A new type of ligand-free Ni-nanoparticles supported on rGO (size distribution average d = 9 ± 3 nm) was prepared and fully characterized via morphological (Fe-SEM), structural (P-XRD, HR-TEM), and spectroscopic (ICP-EOS, XPS) analysis tools. The metal composite was effectively employed in the unprecedented heterogeneously Ni-assisted cross-coupling reaction of aryl/vinyl iodides and thiocarboxylates. A range of sulfur-containing aryl as well as vinyl derivatives (15 examples) was achieved in high yields (up to 82%), under mild reaction conditions, and with wide functional group tolerance.
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.
Electrochemical Thiolation and Borylation of Arylazo Sulfones with Thiols and B2pin2
Wang, Rongkang,Chen, Fangming,Jiang, Lvqi,Yi, Wenbin
supporting information, p. 1904 - 1911 (2021/02/12)
An efficient electrochemical synthesis approach of various unsymmetrical thioethers and arylboronates has been developed. Bench stable arylazo sulfones were used as radical precursors for carbon-heteroatom bond formation under electrochemical conditions. Moreover, the scalability of this approach was evaluated by performing the electrochemical thiolation and borylation of arylazo sulfones with thiols and B2pin2 on a gram scale. This protocol not only avoided the use of stoichiometric oxidants, metal catalysts, activating agents and even added bases, but also exhibited favorable functional group tolerance. (Figure presented.).
Extended Hydrogen Bond Networks for Effective Proton-Coupled Electron Transfer (PCET) Reactions: The Unexpected Role of Thiophenol and Its Acidic Channel in Photocatalytic Hydroamidations
Berg, Nele,Bergwinkl, Sebastian,Nuernberger, Patrick,Horinek, Dominik,Gschwind, Ruth M.
supporting information, p. 724 - 735 (2021/02/01)
Preorganization and aggregation in photoredox catalysis can significantly affect reactivities or selectivities but are often neglected in synthetic and mechanistic studies, since the averaging effect of flexible ensembles can effectively hide the key activation signatures. In addition, aggregation effects are often overlooked due to highly diluted samples used in many UV studies. One prominent example is Knowles's acceleration effect of thiophenol in proton-coupled electron transfer mediated hydroamidations, for which mainly radical properties were discussed. Here, cooperative reactivity enhancements of thiophenol/disulfide mixtures reveal the importance of H-bond networks. For the first time an in-depth NMR spectroscopic aggregation and H-bond analysis of donor and acceptor combined with MD simulations was performed revealing that thiophenol acts also as an acid. The formed phosphate-H+-phosphate dimers provide an extended H-bond network with amides allowing a productive regeneration of the photocatalyst to become effective. The radical and acidic properties of PhSH were substituted by Ph2S2 and phosphoric acid. This provides a handle for optimization of radical and ionic channels and yields accelerations up to 1 order of magnitude under synthetic conditions. Reaction profiles with different light intensities unveil photogenerated amidyl radical reservoirs lasting over minutes, substantiating the positive effect of the H-bond network prior to radical cyclization. We expect the presented concepts of effective activation via H-bond networks and the reactivity improvement via the separation of ionic and radical channels to be generally applicable in photoredox catalysis. In addition, this study shows that control of aggregates and ensembles will be a key to future photocatalysis.
