165904-22-3Relevant academic research and scientific papers
1,2-Boron Shifts of β-Boryl Radicals Generated from Bis-boronic Esters Using Photoredox Catalysis
Kaiser, Daniel,Noble, Adam,Fasano, Valerio,Aggarwal, Varinder K.
, p. 14104 - 14109 (2019)
1,2-Bis-boronic esters are versatile intermediates that enable the rapid elaboration of simple alkene precursors. Previous reports on their selective mono-functionalization have targeted the most accessible position, retaining the more hindered secondary boronic ester. In contrast, we have found that photoredox-catalyzed mono-deboronation generates primary β-boryl radicals that undergo rapid 1,2-boron shift to form thermodynamically favored secondary radicals, allowing for selective transformation of the more hindered boronic ester. The pivotal 1,2-boron shift, which has been demonstrated to be stereoretentive, enables access to a wide range of functionalized boronic esters and has been applied to highly diastereoselective fragmentation and transannular cyclization reactions. Furthermore, its generality has been shown in a radical cascade reaction with an allylboronic ester.
Reaction mechanism of the anomalous formal nucleophilic borylation of organic halides with silylborane: Combined theoretical and experimental studies
Uematsu, Ryohei,Yamamoto, Eiji,Maeda, Satoshi,Ito, Hajime,Taketsugu, Tetsuya
, p. 4090 - 4099 (2015)
Theoretical and experimental studies have been conducted to elucidate the mechanism of the formal nucleophilic boryl substitution of aryl and alkyl bromides with silylborane in the presence of potassium methoxide. Density functional theory was used in conjunction with the artificial force induced reaction method in the current study to determine the mechanism of this reaction. The results of this analysis led to the identification of a unique carbanion-mediated mechanism involving the halogenophilic attack of a silyl nucleophile on the bromine atom of the substrate. These calculations have, therefore, provided a mechanistic rationale for this counterintuitive borylation reaction. Furthermore, the good functional group compatibility and high reactivity exhibited by this reaction toward sterically hindered substrates can be understood in terms of the low activation energy required for the reaction of the silyl nucleophile with the bromine atom of the substrate and the subsequent rapid and selective consumption of the carbanion species by the in situ generated boron electrophile. The results of an experimental study involving the capture of the anion intermediate provided further evidence in support of the generation of a carbanion species during the course of this reaction. The anomalous formal nucleophilic borylation mechanism reported in this study could be used to provide new insights into silicon and boron chemistry.
Palladium-catalyzed benzylic C-H borylation of alkylbenzenes with bis(pinacolato)diboron or pinacolborane
Ishiyama, Tatsuo,Ishida, Kousaku,Takagi, Jun,Miyaura, Norio
, p. 1082 - 1083 (2001)
Borylation at the benzylic C-H bond of alkylbenzenes with bis(pinacolato)diboron [(Me4C2O2)B-B(O2C2Me 4)] or pinacolborane [(Me4C2O2)B-H] was carried out at
Bimetallic Cu(i) complex with a pyridine-bridged bis(1,2,3-triazole-5-ylidene) ligand
Iwasaki, Haruka,Teshima, Yuta,Yamada, Yuji,Ishikawa, Ryuta,Koga, Yuji,Matsubara, Kouki
, p. 5713 - 5719 (2016)
A dinuclear copper(i) complex bearing a mesoionic carbene ligand has been prepared from the corresponding silver analogue and its structure determined spectroscopically. The results revealed that two Cu(i) halide salt molecules were bound to the carbon at
Rh(I)-catalyzed borylation of primary alkyl chlorides
Gong, Tian-Jun,Jiang, Yuan-Ye,Fu, Yao
, p. 397 - 400 (2014)
Rhodium-catalyzed cross-coupling reactions of unactivated primary alkyl chlorides with diboron reagents have been developed as practical methods for the synthesis of alkylboronic esters. These reactions expand the concept and utility of Rh(I)-catalyzed cr
Hierarchical hybrid MnO/Pd-Fe3O4 and CoO/Pd-Fe3O4 nanocomposites as efficient catalysts for hydroboration of styrene
Woo, Hyunje,Park, Junha,Kim, Jiwoong,Park, Sungkyun,Park, Kang Hyun
, p. 52 - 56 (2017)
We report a one-pot synthesis of hierarchical MnO/Pd-Fe3O4 and CoO/Pd-Fe3O4 nanocomposites containing scrolled multilayered nanosheets by controlled thermal decomposition of Fe(CO)5 and reduction of metal precursors [Pd(OAc)2]. During the synthetic process, particles of amorphous MnO and CoO are immobilized on the Pd-Fe3O4 support. These hierarchical nanocomposites follow a stepwise growth mechanism, initially forming Pd-Fe3O4 seeds aggregated from nuclei, followed by growth to produce multilayered MnO/Pd-Fe3O4 or CoO/Pd-Fe3O4 structures. To the best of our knowledge, this is the first report on the hydroboration of styrene with bis(pinacolato)diboron using heterogeneous nanocatalysts. Among these catalysts, CoO/Pd-Fe3O4 nanocomposites showed excellent performance due to the presence of a dual Pd and CoO catalytic system.
Fundamental organometallic chemistry under bimetallic influence: Driving β-hydride elimination and diverting migratory insertion at Cu and Ni
Mazzacano, Thomas J.,Leon, Noel J.,Waldhart, Greyson W.,Mankad, Neal P.
, p. 5518 - 5521 (2017)
Bimetallic effects on stoichiometric β-hydride elimination and migratory insertion reactions were examined. Bimetallic reaction conditions drove β-hydride elimination at Cu, while bimetallic C-B elimination occurred in the absence of β-hydrogens. The inhe
Structure and reactivity of a copper(I)-fused N-heterocyclic carbene complex: Reactivity toward styrenic and strained alkenes
Ondrusek, Brian A.,Opalka, Suzanne M.,Hietsoi, Oleksandr,Shatruk, Michael,McQuade, D. Tyler
, p. 1211 - 1214 (2013)
The synthesis of a fused N-heterocyclic carbene complex is accomplished using a flow-chemistry approach where a fused N-herterocyclic imidazolium chloride is passed through a packed bed of copper(I) oxide. The identity of the resulting complex is confirmed via crystal structure, and the reactivity is examined in the context of alkene hydroboration. We demonstrate that this novel complex can perform the desired reaction whereas the carbene ligand alone cannot. Georg Thieme Verlag Stuttgart New York.
Borohydrogenation reaction method of halide calcium catalyzed olefins
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Paragraph 0024-0029, (2022/01/12)
The present invention discloses a method of borohydrogenation of olefins catalyzed by calcium halide, comprising, under anhydrous and anaerobic conditions, calcium halide added to the mixture of olefins and pinacol borane, stirred at 90 to 110 ° C for 6 t
Neosilyllithium-Catalyzed Hydroboration of Alkynes and Alkenes in the Presence of Pinacolborane (HBpin)
Kumar, Gobbilla Sai,Moorthy, Shruti,Karmakar, Himadri,Singh, Saurabh Kumar,Panda, Tarun K.
supporting information, (2021/11/13)
We report here a novel protocol for the hydroboration of alkynes and alkenes, which in the presence of neosilyllithium (LiCH2SiMe3) (5 mol %) and pinacolborane efficiently results in the formation of corresponding alkenyl and alkyl b
