171364-79-7Relevant articles and documents
Stoichiometric and Catalytic Aryl?Cl Activation and Borylation using NHC-stabilized Nickel(0) Complexes
Kuehn, Laura,Jammal, Dominik G.,Lubitz, Katharina,Marder, Todd B.,Radius, Udo
, p. 9514 - 9521 (2019)
NHC-nickel (NHC=N-heterocyclic carbene) complexes are efficient catalysts for the C?Cl bond borylation of aryl chlorides using NaOAc as a base and B2pin2 (pin=pinacolato) as the boron source. The catalysts [Ni2(ICy)4(μ-(η2:η2)-COD)] (1, ICy=1,3-dicyclohexylimidazolin-2-ylidene; COD=1,5-cyclooctadiene), [Ni(ICy)2(η2-C2H4)] (2), and [Ni(ICy)2(η2-COE)] (3, COE=cyclooctene) compare well with other nickel catalysts reported previously for aryl-chloride borylation with the advantage that no further ligands had to be added to the reaction. Borylation also proceeded with B2neop2 (neop=neopentylglycolato) as the boron source. Stoichiometric oxidative addition of different aryl chlorides to complex 1 was highly selective affording trans-[Ni(ICy)2(Cl)(Ar)] (Ar=4-(F3C)C6H4, 11; 4-(MeO)C6H4, 12; C6H5, 13; 3,5-F2C6H3, 14).
Synthesis, structure, and reactivity of anionic sp2-sp3 diboron compounds: Readily accessible boryl nucleophiles
Pietsch, Sabrina,Neeve, Emily C.,Apperley, David C.,Bertermann, Rüdiger,Mo, Fanyang,Qiu, Di,Cheung, Man Sing,Dang, Li,Wang, Jianbo,Radius, Udo,Lin, Zhenyang,Kleeberg, Christian,Marder, Todd B.
, p. 7082 - 7099 (2015)
Lewis base adducts of tetra-alkoxy diboron compounds, in particular bis(pinacolato)diboron (B2pin2), have been proposed as the active source of nucleophilic boryl species in metal-free borylation reactions. We report the isolation and detailed structural characterization (by solid-state and solution NMR spectroscopy and X-ray crystallography) of a series of anionic adducts of B2pin2 with hard Lewis bases, such as alkoxides and fluoride. The study was extended to alternative Lewis bases, such as acetate, and other diboron reagents. The B(sp2)-B(sp3) adducts exhibit two distinct boron environments in the solid-state and solution NMR spectra, except for [(4-tBuC6H4O)B2pin2]-, which shows rapid site exchange in solution. DFT calculations were performed to analyze the stability of the adducts with respect to dissociation. Stoichiometric reaction of the isolated adducts with two representative series of organic electrophiles - namely, aryl halides and diazonium salts - demonstrate the relative reactivities of the anionic diboron compounds as nucleophilic boryl anion sources.
Aromatic C-H borylation catalyzed by hydrotris(pyrazolyl)borate complexes of rhodium and iridium
Murata, Miki,Odajima, Hiroki,Watanabe, Shinji,Masuda, Yuzuru
, p. 1980 - 1982 (2006)
Dehydrogenative coupling of 4,4,5,5-tetramethyl-1,3,2-dioxaborolane (pinacolborane) with arenes occurred in good yield in the presence of a catalytic amount of [Rh(TpMe2)-(cod)] (TpMe2 = hydrotris(3,5-dimethylpyrazolyl)borate, cod = 1,5-cyclooctadiene), [Ir(Tp)(cod)] (Tp = hydrotris-(pyrazolyl)borate), and related (pyrazolyl)borate complexes. The catalytic activity was strongly affected by substituents on the pyrazolyl rings.
Ruthenium-catalysed dehydrogenative C-H borylation of arenes with pinacolborane
Murata, Miki,Ueda, Yosuke,Hyogo, Mayu,Kohari, Yoshihito,Namikoshi, Takeshi,Watanabe, Shinji
, p. 393 - 396 (2016)
A ruthenium complex prepared in situ from [RuCl2(p-cymene)]2 and TpMe2K[TpMe2 = hydrotris(3,5-dimethylpyrazolyl)borate] is efficient for aromatic C-H borylation with pinacolborane (4,4,5,5-tetramethyl-1,3,2-dioxaborolane). Arenes were borylated at more electron-rich positions. DFT calculations and kinetic isotope effect experiments suggest that the catalytic cycle should involve an electrophilic aromatic substitution with a borenium cation.
B-H bond cleavage via metal-ligand cooperation by dearomatized ruthenium pincer complexes
Anaby, Aviel,Butschke, Burkhard,Ben-David, Yehoshoa,Shimon, Linda J. W.,Leitus, Gregory,Feller, Moran,Milstein, David
, p. 3716 - 3726 (2014)
Organic derivatives of boronic acid are widely used reagents useful in various synthetic applications. A fundamental understanding and the exploration of new reaction pathways of boronic reagents with organometallic systems hold promise for useful advancement in chemical catalysis. Herein we present the reactions of simple boranes with dearomatized ruthenium pincer complexes based on PNP (2,6-bis(di-tert-butylphosphinomethyl)pyridine) or PNN (2-(di-tert-butylphosphinomethyl)-6-(diethylaminomethyl)pyridine) ligands. NMR studies revealed dehydrogenative addition of the borane B-H bond across the metal center and the ligand. Remarkably, new complexes were observed, which contain the boryl moiety at the benzylic carbon of the pincer ligand arm. X-ray crystal structures of new dearomatized boryl pincer complexes were obtained, and DFT calculations revealed mechanistic details of the adduct formation process through a dehydrogenative pathway. In addition, catalytic aryl-boron coupling reactions were explored. The new boryl pincer systems may possibly be useful in future postmodification techniques for ruthenium pincer complexes, as well as in catalytic B-B and B-C coupling reactions.
New Electrosynthesis of Arylboronic Esters from Aromatic Halides and Pinacolborane
Laza, Carine,Dunach, Elisabet
, p. 580 - 583 (2003)
A novel synthesis of arylboronic esters by a reductive electrochemical coupling reaction between aromatic halides and pinacolborane (HBpin, pin = pinacolate) has been carried out leading to arylboronic esters in moderate to good yields.
Unsaturated iridium pyridinedicarboxylate pincer complexes with catalytic activity in borylation of arenes
Hanh Nguyen, Duc,Perez-Torrente, Jesus J.,Lomba, Laura,Victoria Jimenez,Lahoz, Fernando J.,Oro, Luis A.
, p. 8429 - 8435 (2011)
Unsaturated σ,π-cyclooctenyl and hydrido Ir(iii) complexes bearing an unusual tridentate dianionic ONO pincer-type ligand have been straightforwardly obtained from 2,6-pyridinedicarboxylic acid and standard Ir(i) starting materials. These complexes efficiently catalyzed the arene C-H borylation under thermal conditions. The Royal Society of Chemistry 2011.
Comparison of arylboron-based nucleophiles in Ni-catalyzed Suzuki-Miyaura cross-coupling with aryl mesylates and sulfamates
Zhang, Na,Hoffman, David J.,Gutsche, Nicholas,Gupta, Jayesh,Percec, Virgil
, p. 5956 - 5964 (2012)
The efficiency of arylboron-based nucleophiles, boronic acid, potassium trifluoroborate, neopentylglycolboronate, and pinacol boronate in nickel-catalyzed Suzuki-Miyaura cross-coupling reactions with the two C-O electrophiles, mesylates, and sulfamates was compared. Arylboronic acid is the most reactive and most atom-economic of the four boron species studied. Arylpotassium trifluoroborate cross-couples efficiently only in the presence of water. In the absence of water, aryl neopentylglycolboronate is more efficient, less expensive, and more atom-economic than aryl pinacolboronate.
Nickel complexes of 1,2,4-triazole derived amido-functionalized N-heterocyclic carbene ligands: Synthesis, theoretical studies and catalytic application
Kumar, Anuj,Bheeter, Linus Paulin,Gangwar, Manoj Kumar,Sortais, Jean-Baptiste,Darcel, Christophe,Ghosh, Prasenjit
, p. 63 - 70 (2015)
A series of nickel complexes (1-3)b of 1,2,4-triazole derived amido-functionalized N-heterocyclic carbene ligands were synthesized and structurally characterized. In particular, the [1-(R)-4-N-(furan-2-ylmethyl)acetamido-1,2,4-triazol-5-ylidene]2Ni [R = Et (1b), i-Pr (2b) and Bn (3b)] complexes were obtained by the direct reaction of the corresponding triazolium chloride salts (1-3)a by the treatment with NiCl2·6H2O in presence of K2CO3 as a base. The density functional theory studies performed on these complexes reveal highly polar character of the NHC-Ni σ-bonding interaction with corresponding molecular orbital having a maximum contribution (59-69%) from the NHC ligand fragments while that of a minimum contribution (4%) from the central nickel atom. The (1-3)b complexes were found to be moderately active for the catalytic borylation reactions of bromoaryl derivatives by bis(pinacolato)diboron reagent (B2pin2) in the presence of Cs2CO3 as a base at 70 °C.
Phosphorus heterocycles: From laboratory curiosities to ligands in highly efficient catalysts
Weber, Lothar
, p. 563 - 572 (2002)
Phosphabenzenes and phosphaferrocenes were among the first compounds with P-C multiple bonds. For nearly 30 years the chemistry of these molecules was essentially a domain left to basic researchers. Recently, however, it was reported that transition metal complexes with phosphabenzene and phosphaferrocene ligands exhibit remarkable potential as catalysts. Catalysts based on rhodium (I) and various phosphabenzenes appear to be superior to classical systems in the hydroformylation of terminal and internal alkenes. In addition planar-chiral phosphaferrocene species display an excellent performance as directing ligands in a series of enantioselective asymmetric syntheses.
The functionalization of benzene by boranes using trispyrazolylborate complexes
Vetter, Andrew J.,DiBenedetto, Tarah A.,Ritz, Mikhaila D.,Jones, William D.
, (2021)
The catalytic C[sbnd]H activation and borylation of arenes by trispyrazolylborate complexes is reported. Trispyrazolylborate rhodium and iridium complexes have been previously shown to activate a variety of C[sbnd]H bonds. Here, we show the catalytic borylation of arenes by the trispyrazolylborate ethylene complexes Tp'Rh(C2H4)2, and Tp'Ir(C2H4)2.
Direct conversion of arylamines to pinacol boronates: A metal-free borylation process
Mo, Fanyang,Jiang, Yubo,Qiu, Di,Zhang, Yan,Wang, Jianbo
, p. 1846 - 1849 (2010)
Leave the metal out: Arylboronates are produced In moderate to good yields by direct borylation of readily available aryl amines (see scheme). The reaction can be carried out under air at room temperature and transition-metal catalysis is not required. The boronate products can be used without purification in SuzukiMiyaura cross-coupling reactions. Chemical equation representation
Unsaturated iridium(III) complexes supported by a quinolato-carboxylato ONO pincer-type ligand: Synthesis, reactivity, and catalytic C-H functionalization
Nguyen, Duc Hanh,Perez-Torrente, Jesus J.,Jimenez, M. Victoria,Modrego, F. Javier,Gomez-Bautista, Daniel,Lahoz, Fernando J.,Oro, Luis A.
, p. 6918 - 6930 (2013)
The unsaturated σ,π-cyclooctenyl iridium(III) pincer compound [Ir(κ3-hqca)(1-κ-4,5-η-C8H13)] (1) has been prepared by the reaction of [Ir(cod)(CH3CN) 2]BF4 with lithium 8-oxidoquinoline-2-carboxylate (Li 2hqca) and obtained as two isomers derived from the relative disposition of the pincer and the σ,π-cyclooctenyl ligands. Compound 1 can be prepared as a single isomer by reaction of 8-hydroxyquinoline-2- carboxylic acid (H2hqca) with [Ir(μ-OMe)(cod)]2. Reaction of [Ir(μ-OH)(coe)2]2 with H2hqca gave the square-pyramidal iridum(III) complex [IrH(κ3-hqca) (coe)] (3). This compound exists as dinuclear assemblies [IrH(κ 3-hqca)(coe)]2 in noncoordinating solvents and as the corresponding labile mononuclear solvates in more polar solvent solutions. The dimerization of 3 was established by 1H-DOSY NMR spectroscopy and an ESI+ mass spectrum and supported by DFT calculations. Reaction of 3 with pyridine gave the adduct [IrH(κ3-hqca)(coe)(py)] (4) and the bis-pyridine complexes [IrH(κ3-hqca)(R-py)2] (R = H (6), 2-Me (7)) by replacement of the coe ligand. Compound 4 was transformed into the bromo derivative [IrBr(κ3-hqca)(coe)(py)] (5) by reaction with N-bromosuccinimide. Carbonylation of 4 gave the cyclooctenyl complex [Ir(κ3-hqca)(1-κ-C8H 15)(CO)(py)] (8), which is stable only under a carbon monoxide atmosphere. The pincer complexes were active in the catalytic borylation of arenes under thermal conditions.
Borylation of Diazonium Salts by Highly Emissive and Crystalline Carbon Dots in Water
Lei, Tao,Wei, Si-Meng,Feng, Ke,Chen, Bin,Tung, Chen-Ho,Wu, Li-Zhu
, p. 1715 - 1719 (2020)
Efficient borylation reaction of diazonium salts in water is realized for the first time by using easily prepared, highly emissive and crystalline carbon dots. Electron-donating and electron-withdrawing groups on diazonium salts were well tolerated with moderate to good conversion efficiency. Compared with widely used metal complexes, organic dyes and quantum dots, the approach presented herein uses carbon dots, which are nontoxic and possess good biological and medicinal compatibility and high reactivity. Therefore, this approach presents a new prospective use for carbon dots in green chemistry.
Convenient synthesis of arylboronates through a synergistic Pd/Cu-catalyzed miyaura borylation reaction under atmospheric conditions
Ratniyom, Jadsada,Dechnarong, Nattanee,Yotphan, Sirilata,Kiatisevi, Supavadee
, p. 1381 - 1385 (2014)
A highly efficient and practical borylation reaction of aryl iodides with bis(pinacolato)diboron has been established. By using Pd(OAc)2, CuI, and PPh3 as a ligand at room temperature under air in the presence of Cs2CO3, the protocol proved to be general. Various functionalized arylboronates were obtained in moderate to excellent yields. In addition, a possible reaction mechanism was proposed. An efficient borylation reaction of aryl iodides with bis(pinacolato)diboron is developed by using Pd(OAc)2 and CuI. This catalytic system has high catalytic efficiency at room temperature in air and functional-group tolerance for a wide range of substrates. Copyright
Synthesis of two A-B-C type conjugated amphiphilic triblock fullerene derivatives and their application in organic solar cells
Liu, Jikang,Jiang, Pengfei,Wang, Yao,Tu, Guoli
, (2019)
Two A-B-C type conjugated amphiphilic triblock fullerene derivatives C60-2HMTPB and C60-2EHTPB were obtained in multi steps synthesis with three different blocks, and the amphiphilic diblock molecular C60-4TPB was also pre
Palladium-catalyzed borylation of aryl chlorides: Scope, applications, and computational studies
Billingsley, Kelvin L.,Barder, Timothy E.,Buchwald, Stephen L.
, p. 5359 - 5363 (2007)
(Chemical Equation Presented) From chloride to boronate: Catalysts comprising palladium and biaryl monophosphine ligands provide highly active systems for the borylation of aryl and heteroaryl chlorides (see scheme). Symmetrical and unsymmetrical biaryl products can also be prepared directly from two aryl chlorides without isolation of the intermediate boronate esters. Computational studies provide insight into the roles of the biaryl phosphine ligand and the KOAc base in the catalytic cycle.
A Nanographene-Based Two-Dimensional Covalent Organic Framework as a Stable and Efficient Photocatalyst
Jin, Enquan,Fu, Shuai,Hanayama, Hiroki,Addicoat, Matthew A.,Wei, Wenxin,Chen, Qiang,Graf, Robert,Landfester, Katharina,Bonn, Mischa,Zhang, Kai A. I.,Wang, Hai I.,Müllen, Klaus,Narita, Akimitsu
supporting information, (2021/12/22)
Synthesis of covalent organic frameworks (COFs) with desirable organic units furnishes advanced materials with unique functionalities. As an emerging class of two-dimensional (2D) COFs, sp2-carbon-conjugated COFs provide a facile platform to build highly stable and crystalline porous polymers. Herein, a 2D olefin-linked COF was prepared by employing nanographene, namely, dibenzo[hi,st]ovalene (DBOV), as a building block. The DBOV-COF exhibits unique ABC-stacked lattices, enhanced stability, and charge-carrier mobility of ≈0.6 cm2 V?1 s?1 inferred from ultrafast terahertz photoconductivity measurements. The ABC-stacking structure was revealed by the high-resolution transmission electron microscopy and powder X-ray diffraction. DBOV-COF demonstrated remarkable photocatalytic activity in hydroxylation, which was attributed to the exposure of narrow-energy-gap DBOV cores in the COF pores, in conjunction with efficient charge transport following light absorption.
Photochemical and electrochemical C-N borylation of arylhydrazines
Du, Linlin,Sun, Li,Zhang, Hua
supporting information, p. 1716 - 1719 (2022/02/21)
The C-N borylation of arylhydrazine hydrochlorides with bis(pinacolato)diboron was achieved under photochemical and electrochemical conditions, respectively. This novel and scalable transformation provides two efficient and mild transition-metal-free synt
