171364-82-2Relevant articles and documents
Two Symmetrically Bis-substituted Pyrene Derivatives: Synthesis, Photoluminescence, and Electroluminescence
Gong, Xiaojie,Xie, Xiang,Chen, Naiwu,Zheng, Chaoyue,Zhu, Jie,Chen, Runfeng,Huang, Wei,Gao, Deqing
, p. 967 - 973 (2015)
Two kinds of cyanophenyl terminated pyrene derivatives for organic light-emitting diodes were synthesized and characterized by UV/Vis, fluorescence (FL), 1H NMR, MALDI-TOF, CV and TGA. Both compounds exhibited blue photoluminescence and high fluorescent quantum yield of 85% and 75% in solutions. Due to the presence of acetylene spacer, the compound distinguishes itself by high coplanarity, high thermal stability, little Stokes' shift and clear excimer formation in the solid state from the acetylene-free compound. In order to suppress the molecular aggregation, the electroluminescent properties were studied by doing the materials in PVK. The result proved that energy transfer happened from the host PVK to the materials. Two kinds of cyanophenyl terminated pyrene derivatives for OLEDs were synthesized and characterized. Both compounds exhibited blue photoluminescence and high fluorescent quantum yield of 85% and 75% in solutions. The result proved that energy transfer happened from the host PVK to the materials.
A “universal” catalyst for aerobic oxidations to synthesize (hetero)aromatic aldehydes, ketones, esters, acids, nitriles, and amides
Bartling, Stephan,Beller, Matthias,Chandrashekhar, Vishwas G.,Jagadeesh, Rajenahally V.,Rabeah, Jabor,Rockstroh, Nils,Senthamarai, Thirusangumurugan
supporting information, p. 508 - 531 (2022/02/11)
Functionalized (hetero)aromatic compounds are indispensable chemicals widely used in basic and applied sciences. Among these, especially aromatic aldehydes, ketones, carboxylic acids, esters, nitriles, and amides represent valuable fine and bulk chemicals, which are used in chemical, pharmaceutical, agrochemical, and material industries. For their synthesis, catalytic aerobic oxidation of alcohols constitutes a green, sustainable, and cost-effective process, which should ideally make use of active and selective 3D metals. Here, we report the preparation of graphitic layers encapsulated in Co-nanoparticles by pyrolysis of cobalt-piperazine-tartaric acid complex on carbon as a most general oxidation catalyst. This unique material allows for the synthesis of simple, functionalized, and structurally diverse (hetero)aromatic aldehydes, ketones, carboxylic acids, esters, nitriles, and amides from alcohols in excellent yields in the presence of air.
Palladium-catalyzed borylation of aryl bromides and chlorides using phosphatrioxa-adamantane ligands
Lamola, Jairus L.,Moshapo, Paseka T.,Holzapfel, Cedric W.,Christopher Maumela, Munaka
supporting information, (2021/12/13)
Catalysts based on the combination of Pd(OAc)2 and the electron-deficient phosphatrioxa-adamantane ligands are described for borylation of aryl bromides and chlorides. Catalytic evaluation of a small library of phosphatrioxa-adamantane ligands provided some insights on the preferred ligand steric profile for borylation reactions. The corresponding aryl boronate esters were accessed under mild conditions (25–70 °C) and isolated in high yields (up to 96%).
Unreactive C-N Bond Activation of Anilines via Photoinduced Aerobic Borylation
Ji, Shuohan,Qin, Shengxiang,Yin, Chunyu,Luo, Lu,Zhang, Hua
supporting information, p. 64 - 68 (2021/12/27)
Unreactive C-N bond activation of anilines was achieved by photoinduced aerobic borylation. A diverse range of tertiary and secondary anilines were converted to aryl boronate esters in moderate to good yields with wide functional group tolerance under simple and ambient photochemical conditions. This transformation achieved the direct and facile C-N bond activation of unreactive anilines, providing a convenient and practical route transforming widely available anilines into useful aryl boronate esters.
Nickel-Catalyzed Cyanation of Aryl Thioethers
Delcaillau, Tristan,Woenckhaus-Alvarez, Adrian,Morandi, Bill
supporting information, p. 7018 - 7022 (2021/09/13)
A nickel-catalyzed cyanation of aryl thioethers using Zn(CN)2 as a cyanide source has been developed to access functionalized aryl nitriles. The ligand dcype (1,2-bis(dicyclohexylphosphino)ethane) in combination with the base KOAc (potassium acetate) is essential for achieving this transformation efficiently. This reaction involves both a C-S bond activation and a C-C bond formation. The scalability, low catalyst and reagents loadings, and high functional group tolerance have enabled both late-stage derivatization and polymer recycling, demonstrating the reaction's utility across organic chemistry.
Nickel-Catalyzed Reversible Functional Group Metathesis between Aryl Nitriles and Aryl Thioethers
Delcaillau, Tristan,Boehm, Philip,Morandi, Bill
supporting information, p. 3723 - 3728 (2021/04/07)
We describe a new functional group metathesis between aryl nitriles and aryl thioethers. The catalytic system nickel/dcype is essential to achieve this fully reversible transformation in good to excellent yields. Furthermore, the cyanide- and thiol-free reaction shows high functional group tolerance and great efficiency for the late-stage derivatization of commercial molecules. Finally, synthetic applications demonstrate its versatility and utility in multistep synthesis.
Improvement in the Palladium-Catalyzed Miyaura Borylation Reaction by Optimization of the Base: Scope and Mechanistic Study
Barroso, Santiago,Joksch, Markus,Puylaert, Pim,Tin, Sergey,Bell, Stephen J.,Donnellan, Luke,Duguid, Stewart,Muir, Colin,Zhao, Peichao,Farina, Vittorio,Tran, Duc N.,De Vries, Johannes G.
supporting information, p. 103 - 109 (2020/12/22)
Aryl boronic acids and esters are important building blocks in API synthesis. The palladium-catalyzed Suzuki-Miyaura borylation is the most common method for their preparation. This paper describes an improvement of the current reaction conditions. By using lipophilic bases such as potassium 2-ethyl hexanoate, the borylation reaction could be achieved at 35 °C in less than 2 h with very low palladium loading (0.5 mol %). A preliminary mechanistic study shows a hitherto unrecognized inhibitory effect by the carboxylate anion on the catalytic cycle, whereas 2-ethyl hexanoate minimizes this inhibitory effect. This improved methodology enables borylation of a wide range of substrates under mild conditions.
Photo-induced thiolate catalytic activation of inert Caryl-hetero bonds for radical borylation
K?nig, Burkhard,Wang, Hua,Wang, Shun
supporting information, p. 1653 - 1665 (2021/06/17)
Substantial effort is currently being devoted to obtaining photoredox catalysts with high redox power. Yet, it remains challenging to apply the currently established methods to the activation of bonds with high bond dissociation energy and to substrates with high reduction potentials. Herein, we introduce a novel photocatalytic strategy for the activation of inert substituted arenes for aryl borylation by using thiolate as a catalyst. This catalytic system exhibits strong reducing ability and engages non-activated Caryl–F, Caryl–X, Caryl–O, Caryl–N, and Caryl–S bonds in productive radical borylation reactions, thus expanding the available aryl radical precursor scope. Despite its high reducing power, the method has a broad substrate scope and good functional-group tolerance. Spectroscopic investigations and control experiments suggest the formation of a charge-transfer complex as the key step to activate the substrates.
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.).
Decarbonylative Fluoroalkylation at Palladium(II): From Fundamental Organometallic Studies to Catalysis
Lalloo, Naish,Malapit, Christian A.,Taimoory, S. Maryamdokht,Brigham, Conor E.,Sanford, Melanie S.
supporting information, p. 18617 - 18625 (2021/11/16)
This Article describes the development of a decarbonylative Pd-catalyzed aryl-fluoroalkyl bond-forming reaction that couples fluoroalkylcarboxylic acid-derived electrophiles [RFC(O)X] with aryl organometallics (Ar-M′). This reaction was optimized by interrogating the individual steps of the catalytic cycle (oxidative addition, carbonyl de-insertion, transmetalation, and reductive elimination) to identify a compatible pair of coupling partners and an appropriate Pd catalyst. These stoichiometric organometallic studies revealed several critical elements for reaction design. First, uncatalyzed background reactions between RFC(O)X and Ar-M′ can be avoided by using M′ = boronate ester. Second, carbonyl de-insertion and Ar-RF reductive elimination are the two slowest steps of the catalytic cycle when RF = CF3. Both steps are dramatically accelerated upon changing to RF = CHF2. Computational studies reveal that a favorable F2C-H - -X interaction contributes to accelerating carbonyl de-insertion in this system. Finally, transmetalation is slow with X = difluoroacetate but fast with X = F. Ultimately, these studies enabled the development of an (SPhos)Pd-catalyzed decarbonylative difluoromethylation of aryl neopentylglycol boronate esters with difluoroacetyl fluoride.