59693-93-5Relevant academic research and scientific papers
Ni(II) Precatalysts Enable Thioetherification of (Hetero)Aryl Halides and Tosylates and Tandem C?S/C?N Couplings
Martín, M. Trinidad,Marín, Mario,Maya, Celia,Prieto, Auxiliadora,Nicasio, M. Carmen
supporting information, p. 12320 - 12326 (2021/08/09)
Ni-catalyzed C?S cross-coupling reactions have received less attention compared with other C-heteroatom couplings. Most reported examples comprise the thioetherification of most reactive aryl iodides with aromatic thiols. The use of C?O electrophiles in this context is almost uncharted. Here, we describe that preformed Ni(II) precatalysts of the type NiCl(allyl)(PMe2Ar’) (Ar’=terphenyl group) efficiently couple a wide range of (hetero)aryl halides, including challenging aryl chlorides, with a variety of aromatic and aliphatic thiols. Aryl and alkenyl tosylates are also well tolerated, demonstrating, for the first time, to be competent electrophilic partners in Ni-catalyzed C?S bond formation. The chemoselective functionalization of the C?I bond in the presence of a C?Cl bond allows for designing site-selective tandem C?S/C?N couplings. The formation of the two C-heteroatom bonds takes place in a single operation and represents a rare example of dual electrophile/nucleophile chemoselective process.
Visible-Light-Mediated Alkylation of Thiophenols via Electron Donor-Acceptor Complexes Formed between Two Reactants
Cai, Yi-Ping,Nie, Fang-Yuan,Song, Qin-Hua
, p. 12419 - 12426 (2021/09/02)
A metal-free, photocatalyst-free, photochemical system was developed for the direct alkylation of thiophenols via electron donor-acceptor (EDA) complexes (KEDA = 145 M-1) between two reactants, N-hydroxyphthalimide esters as acceptors and thiophenol anions as donors, in the presence of a tertiary amine. The EDA complexes in the reaction system have a broad range of visible-light absorption (400-650 nm) and can trigger the reaction effectively under sunlight.
Nickel-catalyzed oxidative dehydrogenative coupling of alkane with thiol for C(sp3)-S bond formation
Liu, Shengping,Jin, Shengnan,Wang, Hao,Qi, Zaojuan,Hu, Xiaoxue,Qian, Bo,Huang, Hanmin
supporting information, (2021/03/15)
A nickel-catalyzed oxidative dehydrogenative coupling reaction of alkane with thiol for the construction of C(sp3)-S bond has been established, affording more than 50 alkyl thioethers. Notably, pharmaceutical and agrochemicals, such as Provigil, Chlorbenside and Pyridaben, were readily synthesized by this approach. The sterically hindered ligand BC and disulfide which was formed in situ oxidation of thiol, efficiently avoiding nickel-catalyst poisoning. A set of mechanistic experiments disclose both Ni-catalyzed and Ni-free HAA processes.
Photoredox Nickel-Catalyzed C-S Cross-Coupling: Mechanism, Kinetics, and Generalization
Qin, Yangzhong,Sun, Rui,Gianoulis, Nikolas P.,Nocera, Daniel G.
supporting information, p. 2005 - 2015 (2021/02/06)
Photoredox-mediated nickel-catalyzed cross-couplings have evolved as a new effective strategy to forge carbon-heteroatom bonds that are difficult to access with traditional methods. Experimental mechanistic studies are challenging because these reactions involve multiple highly reactive intermediates and perplexing reaction pathways, engendering competing, but unverified, proposals for substrate conversions. Here, we report a comprehensive mechanistic study of photoredox nickel-catalyzed C-S cross-coupling based on time-resolved transient absorption spectroscopy, Stern-Volmer quenching, and quantum yield measurements. We have (i) discovered a self-sustained productive Ni(I/III) cycle leading to a quantum yield φ > 1; (ii) found that pyridinium iodide, formed in situ, serves as the dominant quencher for the excited state photocatalyst and a critical redox mediator to facilitate the formation of the active Ni(I) catalyst; and (iii) observed critical intermediates and determined the rate constants associated with their reactivity. Not only do the findings reveal a complete reaction cycle for C-S cross-coupling, but the mechanistic insights have also allowed for the reaction efficiency to be optimized and the substrate scope to be expanded from aryl iodides to include aryl bromides, thus broadening the applicability of photoredox C-S cross-coupling chemistry.
Visible-Light-Promoted Cross-Coupling Reactions of 4-Alkyl-1,4-dihydropyridines with Thiosulfonate or Selenium Sulfonate: A Unified Approach to Sulfides, Selenides, and Sulfoxides
Li, Jian,Yang, Xin-Er,Wang, Shan-Le,Zhang, Long-Long,Zhou, Xiao-Zhou,Wang, Shun-Yi,Ji, Shun-Jun
supporting information, p. 4908 - 4913 (2020/07/13)
In this paper, a visible-light-promoted cross-coupling of 4-alkyl-1,4-dihydropyridines with thio-/selenium sulfonates under transition-metal-free conditions is described. This strategy features easily available substrates, mild reaction conditions, high yields, and high chemoselectivity. A novel synthetic route for the construction of a sulfide or selenide Csp3-S or Csp3-Se bond under transition-metal-free conditions without an additive oxidant or base is developed. This method is well extended to the synthesis of a class of thiolated or selenylated glycosides that has not been explored before. Sulfoxides were also successfully chemoselectively observed via a facile variation of the atmosphere under photocatalyzed conditions.
Deprotonated Salicylaldehyde as Visible Light Photocatalyst
Zhuang, Yan-Jun,Qu, Jian-Ping,Kang, Yan-Biao
, p. 4386 - 4397 (2020/03/05)
Salicylaldehyde is established as an efficient visible light photocatalyst for the first time. Compared to other simple aldehyde analogies, salicylaldehyde has a unique deprotonative red-shift from 324 to 417 nm and gives rise to the remarkable increase of fluorescence quantum from 0.0368 to 0.4632, thus enabling salicylaldehyde as a visible light (>400 nm) photocatalyst. The experimental investigations suggest that the reactive radical species are generated by sensitization of the substrates by the deprotonated salicylaldehyde through an energy-transfer pathway. Consequently, the C-C cleaving alkylation reactions of N-hydroxyphthalimide esters proceed smoothly in the presence of as low as 1 mol % of salicylaldehyde under the visible-light irradiation, affording desired alkylation products with up to 99% yields. Application in visible-light induced aerobic oxidation of N-alkylpyridinium salts is also reported.
Nickel-Catalyzed Inter- and Intramolecular Aryl Thioether Metathesis by Reversible Arylation
Delcaillau, Tristan,Bismuto, Alessandro,Lian, Zhong,Morandi, Bill
supporting information, p. 2110 - 2114 (2019/12/24)
A nickel-catalyzed aryl thioether metathesis has been developed to access high-value thioethers. 1,2-Bis(dicyclohexylphosphino)ethane (dcype) is essential to promote this highly functional-group-tolerant reaction. Furthermore, synthetically challenging macrocycles could be obtained in good yield in an unusual example of ring-closing metathesis that does not involve alkene bonds. In-depth organometallic studies support a reversible Ni0/NiII pathway to product formation. Overall, this work not only provides a more sustainable alternative to previous catalytic systems based on Pd, but also presents new applications and mechanistic information that are highly relevant to the further development and application of unusual single-bond metathesis reactions.
Preparation method of alkyl sulfide
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Paragraph 0056, (2019/12/02)
The invention relates to a preparation method of alkyl sulfide. The method comprises the following steps: under the protection of nitrogen, sequentially adding transition metal, a nitrogen ligand, a cocatalyst, an oxidant, a solvent, alkane and thiophenol or mercaptan into a reaction tube, carrying out oxidative dehydrogenation coupling reaction at 80-150 DEG C, ending the reaction after 6-48 hours, evaporating the solvent to dryness, and carrying out column chromatography separation to obtain the alkyl sulfide compound. The method is simple in synthesis process, mild in reaction condition, high in yield and easy to industrialize.
Merging Photoredox and Organometallic Catalysts in a Metal–Organic Framework Significantly Boosts Photocatalytic Activities
Zhu, Yuan-Yuan,Lan, Guangxu,Fan, Yingjie,Veroneau, Samuel S.,Song, Yang,Micheroni, Daniel,Lin, Wenbin
supporting information, p. 14090 - 14094 (2018/10/15)
Metal–organic frameworks (MOFs) have been extensively used for single-site catalysis and light harvesting, but their application in multicomponent photocatalysis is unexplored. We report here the successful incorporation of an IrIII photoredox catalyst and a NiII cross-coupling catalyst into a stable Zr12 MOF, Zr12-Ir-Ni, to efficiently catalyze C?S bond formation between various aryl iodides and thiols. The proximity of the IrIII and NiII catalytic components to each other (ca. 0.6 nm) in Zr12-Ir-Ni greatly facilitates electron and thiol radical transfers from Ir to Ni centers to reach a turnover number of 38 500, an order of magnitude higher than that of its homogeneous counterpart. This work highlights the opportunity in merging photoredox and organometallic catalysts in MOFs to effect challenging organic transformations.
CATALYTIC C-X-BOND METATHESIS THROUGH ARYLATION
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Page/Page column 9, (2018/09/28)
The present invention refers to a process for a catalytic aryl transfer to rearrange the backbone of aromatic C-X bonds.
