480424-70-2Relevant articles and documents
Para-selective borylation of monosubstituted benzenes using a transient mediator
Wu, Jie,Wang, Zengwei,Chen, Xiao-Yue,Wu, Yichen,Wang, Daoming,Peng, Qian,Wang, Peng
, p. 336 - 340 (2019/12/09)
Herein, we conceptualized a transient mediator approach that has the capability of para-selective C-H functionalization of monosubstituted aromatics. This approach is enabled by in situ generation of a versatile sulfonium salt via highly electrophilic phenoxathiine or thianthrene dication intermediate which can be readily generated from its sulfoxide with trifluoromethanesulfonic anhydride. Preliminary mechanistic study implied that the remarkable para selectivity might be related to the incredible electrophilicity of thianthrene dication intermediate. The versatility of this approach was demonstrated via para-borylation of various monosubstituted simple aromatics combining the sulfonium salt formation with further photocatalyzed transformation.
Pd-Catalyzed Site-Selective Borylation of Simple Arenes via Thianthrenation?
Chen, Xiao-Yue,Huang, Yu-Hao,Zhou, Jian,Wang, Peng
, p. 1269 - 1272 (2020/08/13)
Site-selective borylation of simple arenes was realized in one pot via an electrophilic thianthrenation/Pd-catalyzed borylation sequence. The key to achieve this operatically simple process is the use of Pd catalysis, which could tolerate the solvent and acidic conditions used in the thianthrenation step. This protocol features mild conditions, broad functional group tolerance, and simple manipulations, and is suitable for late-stage functionalization of a wide range of pharmaceuticals and complex bioactive molecules.
Visible- And UV-Light-Induced Decarboxylative Radical Reactions of Benzoic Acids Using Organic Photoredox Catalysts
Kubosaki, Suzuka,Takeuchi, Haruka,Iwata, Yutaka,Tanaka, Yosuke,Osaka, Kazuyuki,Yamawaki, Mugen,Morita, Toshio,Yoshimi, Yasuharu
, p. 5362 - 5369 (2020/05/19)
Photoinduced decarboxylative radical reactions of benzoic acids with electron-deficient alkenes, diborane, and acetonitrile under organic photoredox catalysis conditions and mild heating afforded adducts, arylboronate esters, and the reduction product, respectively. The reaction is thought to involve single-electron transfer promoted the generation of aryl radicals via decarboxylation. A diverse range of benzoic acids were found to be suitable substrates for this photoreaction. Only our two-molecule organic photoredox system can work well for the direct photoinduced decarboxylation of benzoic acids.
Copper-Photocatalyzed Borylation of Organic Halides under Batch and Continuous-Flow Conditions
Nitelet, Antoine,Thevenet, Damien,Schiavi, Bruno,Hardouin, Christophe,Fournier, Jean,Tamion, Rodolphe,Pannecoucke, Xavier,Jubault, Philippe,Poisson, Thomas
supporting information, p. 3262 - 3266 (2019/02/13)
The copper-photocatalyzed borylation of aryl, heteroaryl, vinyl and alkyl halides (I and Br) was reported. The reaction proceeded using a new heteroleptic Cu complex under irradiation with blue LEDs, giving the corresponding boronic-acid esters in good to excellent yields. The reaction was extended to continuous-flow conditions to allow an easy scale-up. The mechanism of the reaction was studied and a mechanism based on a reductive quenching (CuI/CuI*/Cu0) was suggested.
Palladium-Catalyzed Decarbonylative Borylation of Carboxylic Acids: Tuning Reaction Selectivity by Computation
Liu, Chengwei,Ji, Chong-Lei,Hong, Xin,Szostak, Michal
supporting information, p. 16721 - 16726 (2018/11/30)
Decarbonylative borylation of carboxylic acids is reported. Carbon electrophiles are generated directly after reagent-enabled decarbonylation of the in situ accessible sterically-hindered acyl derivative of a carboxylic acid under catalyst controlled conditions. The scope and the potential impact of this method are demonstrated in the selective borylation of a variety of aromatics (>50 examples). This strategy was used in the late-stage derivatization of pharmaceuticals and natural products. Computations reveal the mechanistic details of the unprecedented C?O bond activation of carboxylic acids. By circumventing the challenging decarboxylation, this strategy provides a general synthetic platform to access arylpalladium species for a wide array of bond formations from abundant carboxylic acids. The study shows a powerful combination of experiment and computation to predict decarbonylation selectivity.
Rhodium-Catalyzed ipso-Borylation of Alkylthioarenes via C-S Bond Cleavage
Uetake, Yuta,Niwa, Takashi,Hosoya, Takamitsu
supporting information, p. 2758 - 2761 (2016/06/15)
Rhodium-catalyzed transformation of alkyl aryl sulfides into arylboronic acid pinacol esters via C-S bond cleavage is reported. In combination with transition-metal-catalyzed sulfanyl group-guided regioselective C-H borylation reactions of alkylthioarenes, this method allows the synthesis of a diverse range of multisubstituted arenes.
Directed ortho borylation of phenol derivatives catalyzed by a silica-supported iridium complex
Yamazaki, Kenji,Kawamorita, Soichiro,Ohmiya, Hirohisa,Sawamura, Masaya
supporting information; experimental part, p. 3978 - 3981 (2010/10/21)
The directed ortho borylation of phenol derivatives protected with an N,N-diethylcarbamoyl group was efficiently catalyzed by an immobilized monophosphine-Ir system, which was prepared in situ from [Ir(OMe)(cod)] 2 and a silica-supported, compact phosphine. The utility of the carbamoyloxy group as a leaving group for metal-catalyzed cross-coupling reactions was demonstrated by its utilization in the synthesis of a terphenyl derivative.
