171364-78-6Relevant articles and documents
Palladium-catalyzed borylation of phenyl bromides and application in one-pot Suzuki-Miyaura biphenyl synthesis
Broutin, Pierre-Emmanuel,Cerna, Igor,Campaniello, Maria,Leroux, Frederic,Colobert, Francoise
, p. 4419 - 4422 (2004)
(Chemical equation presented) The coupling reaction of pinacolborane with various aryl bromides in the presence of a catalytic amount of Pd(OAc) 2 together with DPEphos as ligand and Et3N as base provided arylboronates. High yields were obtained in the case of electron-donor substituted aryl bromides. The direct preparation of arylboronates allowed the one-pot, two-step synthesis of unsymmetrical biaryls in high yields.
Electrochemical Radical Borylation of Aryl Iodides
Hong, Junting,Liu, Qianyi,Li, Feng,Bai, Guangcan,Liu, Guoquan,Li, Man,Nayal, Onkar S.,Fu, Xuefeng,Mo, Fanyang
, p. 347 - 351 (2019)
Herein, we report the first electrochemical strategy for the borylation of aryl iodides via a radical pathway using current as a driving force. A mild reaction condition allows an assorted range of readily available aryl iodides to be proficiently converted into synthetically valuable arylboronic esters under transition metal catalyst-free conditions. Moreover, this method also shows good functional group tolerance. Initial control mechanistic experiments reveal the formation of aryl radical as a key intermediate and the current plays an important role in the generation of radical intermediate.
Microwave enhanced formation of electron rich arylboronates
Appukkuttan, Prasad,Van Der Eycken, Erik,Dehaen, Wim
, p. 1204 - 1206 (2003)
Microwave assisted synthesis of eight electron rich aryl boronates (2a-c, 4, 6a-d) via palladium catalyzed reactions of the corresponding aryl bromides with bis(pinacolato)diboron are described. Compared to conventional heating conditions, dramatic rate e
Cesium carbonate mediated borylation of aryl iodides with diboron in methanol
Zhang, Jieming,Wu, Hai-Hong,Zhang, Junliang
, p. 6263 - 6266 (2013)
Herein we describe the unexpected borylation of aryl iodides promoted by a Cs2CO3 and MeOH system. This formal nucleophilic boryl substitution could be applied to a wide range of functionalized aryl iodide compounds. The preliminary results indicate that this process is neither copper catalyzed nor radical mediated. Copyright
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.
, p. 103 - 109 (2021)
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.
Remote steric control for undirected meta-selective C-H activation of arenes
Asako, Sobi,Ilies, Laurean,Jin, Yushu,Ramadoss, Boobalan
, p. 658 - 663 (2022/02/21)
Regioselective functionalization of arenes remains a challenging problem in organic synthesis. Steric interactions are often used to block sites adjacent to a given substituent, but they do not distinguish the remaining remote sites. We report a strategy
Activation of Aryl Carboxylic Acids by Diboron Reagents towards Nickel-Catalyzed Direct Decarbonylative Borylation
Deng, Xi,Guo, Jiandong,Su, Weiping,Wang, Xiaotai,Zhang, Xiaofeng
supporting information, p. 24510 - 24518 (2021/08/12)
The Ni-catalyzed decarbonylative borylation of (hetero)aryl carboxylic acids with B2cat2 has been achieved without recourse to any additives. This Ni-catalyzed method exhibits a broad substrate scope covering poorly reactive non-ortho-substituted (hetero)aryl carboxylic acids, and tolerates diverse functional groups including some of the groups active to Ni0 catalysts. The key to achieve this decarbonylative borylation reaction is the choice of B2cat2 as a coupling partner that not only acts as a borylating reagent, but also chemoselectively activates aryl carboxylic acids towards oxidative addition of their C(acyl)?O bond to Ni0 catalyst via the formation of acyloxyboron compounds. A combination of experimental and computational studies reveals a detailed plausible mechanism for this reaction system, which involves a hitherto unknown concerted decarbonylation and reductive elimination step that generates the aryl boronic ester product. This mode of boron-promoted carboxylic acid activation is also applicable to other types of reactions.
Generation of Aryllithium Reagents from N -Arylpyrroles Using Lithium
Ozaki, Tomoya,Kaga, Atsushi,Saito, Hayate,Yorimitsu, Hideki
, p. 3019 - 3028 (2021/06/02)
Treatment of 1-aryl-2,5-diphenylpyrroles with lithium powder in tetrahydrofuran at 0 °C results in the generation of the corresponding aryllithium reagents through reductive C-N bond cleavage.
Nickel-Catalyzed Ipso-Borylation of Silyloxyarenes via C-O Bond Activation
Pein, Wesley L.,Wiensch, Eric M.,Montgomery, John
supporting information, (2021/06/28)
The conversion of silyloxyarenes to boronic acid pinacol esters via nickel catalysis is described. In contrast to other borylation protocols of inert C-O bonds, the method is competent in activating the carbon-oxygen bond of silyloxyarenes in isolated aromatic systems lacking a directing group. The catalytic functionalization of benzyl silyl ethers was also achieved under these conditions. Sequential cross-coupling reactions were achieved by leveraging the orthogonal reactivity of silyloxyarenes, which could then be functionalized subsequently.
Reductive Electrophotocatalysis: Merging Electricity and Light to Achieve Extreme Reduction Potentials
Kim, Hyunwoo,Kim, Hyungjun,Lambert, Tristan H.,Lin, Song
supporting information, p. 2087 - 2092 (2020/02/04)
We describe a new electrophotocatalytic strategy that harnesses the power of light and electricity to generate an excited radical anion with a reducing potential of -3.2 V vs SCE, which can be used to activate substrates with very high reduction potentials (Ered ≈ -1.9 to -2.9 V). The resultant aryl radicals can be engaged in various synthetically useful transformations to furnish arylboronate, arylstannane, and biaryl products.
