- Cu-mediated: vs. Cu-free selective borylation of aryl alkyl sulfones
-
A Cu-catalysed borylation of aryl alkyl sulfones was developed for the high yield synthesis of versatile arylboronic esters using a readily prepared NHC-Cu catalyst. In addition, the selective cleavage of either alkyl(C)-sulfonyl or aryl(C)-sulfonyl bonds
- Hu, Jiefeng,Huang, Mingming,Marder, Todd B.,Radius, Udo,Tang, Man,Westcott, Stephen A.
-
supporting information
p. 395 - 398
(2022/01/19)
-
- Sequential Ir/Cu-Mediated Method for the Meta-Selective C-H Radiofluorination of (Hetero)Arenes
-
This article describes a sequential Ir/Cu-mediated process for the meta-selective C-H radiofluorination of (hetero)arene substrates. In the first step, Ir-catalyzed C(sp2)-H borylation affords (hetero)aryl pinacolboronate (BPin) esters. The intermediate organoboronates are then directly subjected to copper-mediated radiofluorination with [18F]tetrabutylammonium fluoride to afford fluorine-18 labeled (hetero)arenes in high radiochemical yield and radiochemical purity. This entire process is performed on a benchtop without Schlenk or glovebox techniques and circumvents the need to isolate (hetero)aryl boronate esters. The reaction was automated on a TracerLab FXFN module with 1,3-dimethoxybenzene and a meta-tyrosine derivative. The products, [18F]1-fluoro-3,5-dimethoxybenzene and an 18F-labeled meta-tyrosine derivative, were obtained in 37 ± 5% isolated radiochemical yield and >99% radiochemical purity and 25% isolated radiochemical yield and 99% radiochemical purity, and 0.52 Ci/μmol (19.24 GBq/μmol) molar activity (Am), respectively.
- Wright, Jay S.,Sharninghausen, Liam S.,Preshlock, Sean,Brooks, Allen F.,Sanford, Melanie S.,Scott, Peter J. H.
-
supporting information
p. 6915 - 6921
(2021/05/29)
-
- Cross-Coupling through Ag(I)/Ag(III) Redox Manifold
-
In ample variety of transformations, the presence of silver as an additive or co-catalyst is believed to be innocuous for the efficiency of the operating metal catalyst. Even though Ag additives are required often as coupling partners, oxidants or halide scavengers, its role as a catalytically competent species is widely neglected in cross-coupling reactions. Most likely, this is due to the erroneously assumed incapacity of Ag to undergo 2e? redox steps. Definite proof is herein provided for the required elementary steps to accomplish the oxidative trifluoromethylation of arenes through AgI/AgIII redox catalysis (i. e. CEL coupling), namely: i) easy AgI/AgIII 2e? oxidation mediated by air; ii) bpy/phen ligation to AgIII; iii) boron-to-AgIII aryl transfer; and iv) ulterior reductive elimination of benzotrifluorides from an [aryl-AgIII-CF3] fragment. More precisely, an ultimate entry and full characterization of organosilver(III) compounds [K]+[AgIII(CF3)4]? (K-1), [(bpy)AgIII(CF3)3] (2) and [(phen)AgIII(CF3)3] (3), is described. The utility of 3 in cross-coupling has been showcased unambiguously, and a large variety of arylboron compounds was trifluoromethylated via [AgIII(aryl)(CF3)3]? intermediates. This work breaks with old stereotypes and misconceptions regarding the inability of Ag to undergo cross-coupling by itself.
- Demonti, Luca,Mézailles, Nicolas,Nebra, Noel,Saffon-Merceron, Nathalie
-
supporting information
p. 15396 - 15405
(2021/10/12)
-
- Organic compound and electroluminescent device using same
-
The present invention provides an organic compound and an electroluminescent device using the same. The organic compound has a structure represented by a formula I, and the organic compound provided by the present invention is a D-carbazole-A configuratio
- -
-
Paragraph 0065-0067; 0111-0113
(2021/01/29)
-
- Direct C?H Borylation of Arenes Catalyzed by Saturated Hydride-Boryl-Iridium-POP Complexes: Kinetic Analysis of the Elemental Steps
-
The saturated trihydride IrH3{κ3-P,O,P-[xant(PiPr2)2]} (1; xant(PiPr2)2=9,9-dimethyl-4,5-bis(diisopropylphosphino)xanthene) activates the B?H bond of two molecules of pinacolborane (HBpin) to give H2, the hydride-boryl derivatives IrH2(Bpin){κ3-P,O,P-[xant(PiPr2)2]} (2) and IrH(Bpin)2{κ3-P,O,P-[xant(PiPr2)2]} (3) in a sequential manner. Complex 3 activates a C?H bond of two molecules of benzene to form PhBpin and regenerates 2 and 1, also in a sequential manner. Thus, complexes 1, 2, and 3 define two cycles for the catalytic direct C?H borylation of arenes with HBpin, which have dihydride 2 as a common intermediate. C?H bond activation of the arenes is the rate-determining step of both cycles, as the C?H oxidative addition to 3 is faster than to 2. The results from a kinetic study of the reactions of 1 and 2 with HBpin support a cooperative function of the hydride ligands in the B?H bond activation. The addition of the boron atom of the borane to a hydride facilitates the coordination of the B?H bond through the formation of κ1- and κ2-dihydrideborate intermediates.
- Esteruelas, Miguel A.,Martínez, Antonio,Oliván, Montserrat,O?ate, Enrique
-
supporting information
p. 12632 - 12644
(2020/09/09)
-
- Facile and economical Miyaura borylation and one-pot Suzuki–Miyaura cross-coupling reaction
-
Facile and economical method for Miyaura borylation reaction between B2pin2 and aryl bromides is reported. The catalytic system containing 2 mol% PdCl2(PPh3)2 and KOAc serves to enable borylations to occur under solvent-free and atmospheric conditions. The developed protocol can be applied to synthesize symmetrical and unsymmetrical biaryls via one-pot two-step Suzuki–Miyaura cross-coupling reaction and also offers the up-scalability.
- Boontiem, Phongsakorn,Kiatisevi, Supavadee
-
-
- Highly Selective and Divergent Acyl and Aryl Cross-Couplings of Amides via Ir-Catalyzed C-H Borylation/N-C(O) Activation
-
Herein, we demonstrate that amides can be readily coupled with nonactivated arenes via sequential Ir-catalyzed C-H borylation/N-C(O) activation. This methodology provides facile access to biaryl ketones and biaryls by the sterically controlled Ir-catalyzed C-H borylation and divergent acyl and decarbonylative amide N-C(O) and C-C activation. The methodology diverts the traditional acylation and arylation regioselectivity, allowing us to directly utilize readily available arenes and amides to produce valuable ketone and biaryl motifs.
- Gao, Pengcheng,Szostak, Michal
-
supporting information
p. 6010 - 6015
(2020/07/30)
-
- Copper-catalysed borylation of aryl chlorides
-
We report herein the first Cu-catalysed borylation of a wide range of aryl chlorides with different electronic and steric properties using a readily prepared NHC-stabilised Cu catalyst and KOtBu as the base with B2pin2 (pin = pinacolato) as the boron reagent. The aryl chlorides are converted into their corresponding arylboronic esters in good yields. The new procedure shows broad functional group tolerance, and B2neop2 (neop = neopentyl glycolato) can also be applied as the boron reagent.
- Kuehn, Laura,Huang, Mingming,Radius, Udo,Marder, Todd B.
-
supporting information
p. 6601 - 6606
(2019/07/16)
-
- Pluripotent Features of Doubly Thiophene-Fused Benzodiphospholes as Organic Functional Materials
-
Linear ladder-type π-conjugated molecules have attracted much interest because of their intriguing physicochemical properties. To modulate their electronic structures, an effective strategy is to incorporate main-group elements into ladder-type π-conjugated molecules. In line with this strategy, a variety of ladder-type π-conjugated molecules with main-group elements have been synthesized to explore their potential utility as organic functional materials. In this context, phosphole-based π-conjugated molecules are highly attractive, owing to their unique optical and electrochemical properties, which arise from the phosphorus atom. Herein, the synthesis and physicochemical properties of doubly thiophene-fused benzodiphospholes, as a new class of phosphole-based ladder-type π-conjugated molecule, are reported. Systematic investigations into the physicochemical properties of doubly thiophene-fused benzodiphospholes revealed their pluripotent features: intense near-infrared fluorescence, excellent two-photon absorption property, and remarkably high electron-transporting ability. This study demonstrates the potential utility of doubly thiophene-fused benzodiphospholes as organic functional materials for biological imaging, nonlinear optics, organic transistors, and organic photovoltaics.
- Higashino, Tomohiro,Ishida, Keiichi,Sakurai, Tsuneaki,Seki, Shu,Konishi, Tatsuki,Kamada, Kenji,Imahori, Hiroshi,Imahori, Hiroshi
-
supporting information
p. 6425 - 6438
(2019/04/26)
-
- Energy level tuning of ‘Z'-shaped small molecular non-fullerene electron acceptors based on a dipyrrolo[2,3-b:2′,3′-e]pyrazine-2,6(1H,5H)-dione acceptor unit for organic photovoltaic applications: a joint experimental and DFT investigation on the effect o
-
Three different fluorine (4-CF3, 3,5-CF3 and 3,4,5-F) end-capped, A2-π-A1-π-A2 type small molecular non-fullerene acceptor molecules (1CFPzDP, 2CFPzDP, and 3FPzDP) containing a common central core acc
- Sivakumar, Gangala,Paramasivam, Mahalingavelar,Bharath, Dyaga,Rao, Vaidya Jayathirtha
-
p. 5173 - 5186
(2019/03/29)
-
- Hydrogen Atom Transfer Induced Boron Retaining Coupling of Organoboronic Esters and Organolithium Reagents
-
α-Functionalization of alkyl boronic esters and homologation of aryl boronic esters by regioselective radical C(sp3)-H activation in boron-ate complexes is reported. Reaction of commercial or readily accessed aryl boronic acid pinacol esters with alkyl lithium reagents provides boron-ate complexes. Selective α-C-H abstraction by in situ generated trifluoromethyl radicals leads to radical anions that undergo electron transfer oxidation followed by 1,2-aryl/alkyl migration from boron to carbon to give the α-arylated/alkylated alkyl boronic esters. The valuable boronic ester functionality remains in the products and the cheap trifluoromethyl iodide acts as the oxidant in these C-C couplings. The 1,2-alkyl migration from boron to carbon is highly stereospecific allowing access to stereoisomerically pure boronic esters.
- Wang, Dinghai,Mück-Lichtenfeld, Christian,Studer, Armido
-
supporting information
p. 14126 - 14130
(2019/10/11)
-
- Sterically controlled C-H/C-H homocoupling of arenes: Via C-H borylation
-
A mild one-pot protocol for the synthesis of symmetrical biaryls by sequential Ir-catalyzed C-H borylation and Cu-catalyzed homocoupling of arenes is described. The regiochemistry of the biaryl formed is sterically controlled as dictated by the C-H borylation step. The methodology is also successfully extended to heteroarenes. Some of the products obtained by this approach are impossible to obtain via the Ullmann or the Suzuki coupling protocols. Finally, we have shown a one-pot sequence describing C-H borylation/Cu-catalyzed homocoupling/Pd-catalyzed Suzuki coupling to obtain π-extended arene frameworks.
- Pei, Xiaocong,Zhou, Guan,Li, Xuejing,Xu, Yuchen,Panicker, Resmi C.,Srinivasan, Rajavel
-
supporting information
p. 5703 - 5707
(2019/06/19)
-
- Efficient Synthesis of Aryl Boronates via Cobalt-Catalyzed Borylation of Aryl Chlorides and Bromides
-
An efficient catalytic system based on a Co(II)-NHC precursor has been developed for the cross coupling of bis(pinacolato)diboron with aryl halides including aryl chlorides, affording the aryl boronates in good to excellent yields. A wide range of functional groups are tolerated under mild reaction conditions. The reaction shows excellent chemoselectivity for bromide over chloride. Preliminary mechanistic investigations show that the catalytic cycle may rely on a cobalt(I)-(III) redox couple.
- Verma, Piyush Kumar,Mandal, Souvik,Geetharani
-
p. 4049 - 4054
(2018/05/22)
-
- Ir-Catalyzed Intramolecular Transannulation/C(sp2)-H Amination of 1,2,3,4-Tetrazoles by Electrocyclization
-
An efficient strategy for the intramolecular denitrogenative transannulation/C(sp2)-H amination of 1,2,3,4-tetrazoles bearing C8-substituted arenes, heteroarenes, and alkenes is described. The process involves the generation of the metal-nitrene intermediate from tetrazole by the combination of [CpIrCl2]2 and AgSbF6. It has been shown that the reaction proceeds via an unprecedented electrocyclization process. The method has been successfully applied for the synthesis of a diverse array of α-carbolines and 7-azaindoles.
- Das, Sandip Kumar,Roy, Satyajit,Khatua, Hillol,Chattopadhyay, Buddhadeb
-
supporting information
p. 8429 - 8433
(2018/07/09)
-
- Palladium-Catalyzed Synthesis of 2,3-Diaryl- N-methylindoles from ortho-Alkynylanilines and Aryl Pinacol Boronic Esters
-
A palladium-catalyzed synthesis of 2,3-diaryl-N-methylindoles from o-alkynylanilines and aryl pinacol boronic esters was developed. The system possesses high functional group tolerance and a broad substrate scope with a variety of aryl pinacol boronic est
- Luo, Yue-Gui,Basha, R. Sidick,Reddy, Daggula Mallikarjuna,Xue, Yong-Jing,Chen, Te-Hsuan,Lee, Chin-Fa
-
supporting information
p. 6872 - 6876
(2018/11/21)
-
- Rhodium-Catalyzed Decarbonylative Borylation of Aromatic Thioesters for Facile Diversification of Aromatic Carboxylic Acids
-
Transformation of aromatic thioesters into arylboronic esters was achieved efficiently using a rhodium catalyst. The broad functional-group tolerance and mild conditions of the method have allowed for the two-step decarboxylative borylation of a wide range of aromatic carboxylic acids, including commercially available drugs.
- Ochiai, Hidenori,Uetake, Yuta,Niwa, Takashi,Hosoya, Takamitsu
-
p. 2482 - 2486
(2017/02/23)
-
- Effect of the CF3 Substituents on the Charge-Transfer Kinetics of High-Efficiency Cyclometalated Ruthenium Sensitizers
-
Six thiocyanate-free complexes, DUY1-DUY6, were synthesized, and their application in a dye-sensitized solar cell was studied to explore the effect of the CF3 substituent positioned in the ancillary ligand and the structure of the anchoring ligand on the physicochemical properties, charge-transfer kinetics, and photovoltaic properties of ruthenium sensitizers. When the electron-withdrawing groups were installed on the cyclometalating ligands and their π conjugation of the ancillary ligand was extended, the frontier orbital energy levels of the ruthenium complex appeared to be sufficient for effective electron injection and dye regeneration, at the same time having high light-harvesting ability. Two electron-withdrawing CF3 groups meta to the cyclometalated position reduce the electron density at the metal center less seriously than o-CF3 and p-CF3 groups. The sensitizers containing a m-CF3 group also reveal a more favorable distribution of β lowest unoccupied spin orbital for interaction between the oxidized dyes and the iodide ion, which promotes dye regeneration. The absorption profiles of DUY1-DUY4 adsorbed a TiO2 film extended to longer wavelength compared to those in an N,N-dimethylformamide solution, especially DUY1 and DUY2 dyes, which have λmax red shifts of up to 30 nm. The DUY2-dyed cell exhibited the highest efficiency of 9.03%, while the power conversion efficiencies of DUY1-, DUY3-, DUY4-, and N719-based devices were 7.40%, 7.01%, 8.92%, and 8.63%, respectively. DUY5 and DUY6 (the side products of DUY3 and DUY4) without anchoring groups have very weak physical adsorption on a TiO2 anode. The corresponding cells exhibit very low efficiency (0.1%), although both dyes have high light-harvesting ability and proper frontier orbital energy levels.
- Nguyen, The-Duy,Lin, Chun-Han,Wu, Chun-Guey
-
supporting information
p. 252 - 260
(2017/01/13)
-
- Cobalt-Catalyzed Regioselective Borylation of Arenes: N-Heterocyclic Silylene as an Electron Donor in the Metal-Mediated Activation of C?H Bonds
-
C?H Borylation of arenes has been a subject of great interest recently because of its atom-economy and the wide applicability of borylated products in value-added synthesis. A new bis(silylene)cobalt(II) complex bearing a bis(N-heterocyclic silylene)-pyridine pincer ligand (SiNSi) has been synthesized and structurally characterized. It enabled the regioselective catalytic C?H borylation of pyridines, furans, and fluorinated arenes. Notably, it exhibited complementary regioselectivity for the borylation of fluorinated arenes compared to previously known catalytic systems, demonstrating that N-heterocyclic silylene donors have enormous potential in metal-catalyzed catalytic applications.
- Ren, Hailong,Zhou, Yu-Peng,Bai, Yunping,Cui, Chunming,Driess, Matthias
-
supporting information
p. 5663 - 5667
(2017/04/28)
-
- Palladium-catalyzed ortho-C-H arylation of acetophenone oxime ethers with aryl pinacol boronic esters
-
We report an efficient palladium-catalyzed ortho-C-H arylation of acetophenone oxime ethers with aryl pinacol boronic esters, leading to the synthesis of biaryl derivatives in good yields. Sequential process of iridiumcatalyzed C-H borylation and palladiu
- Reddy, Daggula Mallikarjuna,Wang, Shao-Chien,Du, Kai,Lee, Chin-Fa
-
p. 10070 - 10076
(2018/05/31)
-
- Ruthenium-catalysed dehydrogenative C-H borylation of arenes with pinacolborane
-
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.
- Murata, Miki,Ueda, Yosuke,Hyogo, Mayu,Kohari, Yoshihito,Namikoshi, Takeshi,Watanabe, Shinji
-
p. 393 - 396
(2016/07/21)
-
- Iridium-bipyridine periodic mesoporous organosilica catalyzed direct C-H borylation using a pinacolborane
-
Heterogeneous catalysis for direct C-H borylation of arenes and heteroarenes in the combination of iridium (Ir) complex fixed on periodic mesoporous organosilica containing bipyridine ligands within the framework (Ir-BPy-PMO) and pinacolborane (HBpin) is reported. Ir-BPy-PMO showed higher catalytic activity toward the borylation of benzene with inexpensive HBpin compared to expensive bis(pinacolato)diboron (B2pin2). The precatalyst could be handled without the use of a glove box. The catalyst was easily recovered from reaction mixtures by simple filtration under air. The recovered catalyst still showed good catalytic activity for at least three more times for the borylation of benzene. A variety of arenes and heteroarenes were successfully borylated with high boron efficiency by Ir-BPy-PMO using HBpin, whereas almost no activity was observed for borylation of some heteroarenes with B2pin2. The system using Ir-BPy-PMO and HBpin was also utilized in syntheses of multi-boronated thiophene-based building blocks containing ladder-, acenefused-, and fused-thiophene skeletons. The combination of a stable and reusable solid catalyst and inexpensive HBpin is expected to be superior to conventional approaches for the development of industrial applications.
- Maegawa, Yoshifumi,Inagaki, Shinji
-
supporting information
p. 13007 - 13016
(2016/01/09)
-
- Efficient Rh-catalyzed C-H borylation of arene derivatives under photochemical conditions
-
Photocatalysis allows innovations in organic synthesis. Among the various catalytic reactions, CH-functionalizations offer valuable possibilities for the refinement of easily available building blocks. In this respect, catalytic borylation is of interest, too. So far, most of the catalytic borylation reactions are performed under thermal conditions at comparably high temperatures. Here, we describe a new synthetic route for efficient borylation reactions of arenes using a photocatalytic pathway. This novel approach allows the synthesis of a broad variety of borylated arenes and heteroarenes under mild conditions. Applying trans-[Rh(PMe3)2(CO)Cl] as an active photocatalyst and HBPin as an boron source, we achieved high TON. A catalytic cycle that relies on a Rh(i)-Rh(iii) interconversion is proposed.
- Bheeter, Charles Beromeo,Chowdhury, Abhishek Dutta,Adam, Rosa,Jackstell, Ralf,Beller, Matthias
-
supporting information
p. 10336 - 10340
(2015/10/28)
-
- Amine-borane complexes: Air- and moisture-stable partners for palladium-catalyzed borylation of aryl bromides and chlorides
-
A method for using amine-borane complexes directly in palladium catalyzed borylation has been developed. The reaction proceeds through the sequential formation of a boronium species followed by deprotonation leading to the aminoborane. This reagent is then directly used in the borylation process leading, after work-up, to various boronic acid derivatives. The reaction was applied to (hetero)aryl triflates, iodides, bromides and chlorides.
- Guerrand, Hélène D. S.,Vaultier, Michel,Pinet, Sandra,Pucheault, Mathieu
-
p. 1167 - 1174
(2015/04/22)
-
- Palladium(ii)-catalysed ortho-arylation of N-benzylpiperidines
-
PdII-catalysed ortho-arylation of benzylic heterocycles with arylboronic acid pinacol esters (Ar-BPin) via directed C-H bond activation to generate the desired biaryl products is reported. This methodology is efficient and applicable to a wide range of functionalised Ar-BPin and benzylic heterocycles, allowing the direct synthesis of important biaryl motifs in modest to good yield. This journal is
- Tan, Peng Wen,Haughey, Maxwell,Dixon, Darren J.
-
supporting information
p. 4406 - 4409
(2015/03/18)
-
- Para -C-H borylation of benzene derivatives by a bulky iridium catalyst
-
A highly para-selective aromatic C-H borylation has been accomplished. By a new iridium catalyst bearing a bulky diphosphine ligand, Xyl-MeO-BIPHEP, the C-H borylation of monosubstituted benzenes can be affected with para-selectivity up to 91%. This catalytic system is quite different from the usual iridium catalysts that cannot distinguish meta- and para-C-H bonds of monosubstituted benzene derivatives, resulting in the preferred formation of meta-products. The para-selectivity increases with increasing bulkiness of the substituent on the arene, indicating that the regioselectivity of the present reaction is primarily controlled by steric repulsion between substrate and catalyst. Caramiphen, an anticholinergic drug used in the treatment of Parkinsons disease, was converted into five derivatives via our para-selective borylation. The present [Ir(cod)OH]2/Xyl-MeO-BIPHEP catalyst represents a unique, sterically controlled, para-selective, aromatic C-H borylation system that should find use in streamlined, predictable chemical synthesis and in the rapid discovery and optimization of pharmaceuticals and materials.
- Saito, Yutaro,Segawa, Yasutomo,Itami, Kenichiro
-
supporting information
p. 5193 - 5198
(2015/05/05)
-
- Fluorine-controlled C-H borylation of arenes catalyzed by a PSiN-pincer platinum complex
-
An efficient, regioselective synthesis of fluorine-substituted arylboronic esters was achieved through fluorine-controlled C-H borylation of arenes with diboron catalyzed by a PSiN-platinum complex. The promising utility of the PSiN-platinum catalyst and its unique regioselectivity were demonstrated for the first time, which would complement the well-developed Ir-catalyzed C-H borylation.
- Takaya, Jun,Ito, Shisei,Nomoto, Hironori,Saito, Narumasa,Kirai, Naohiro,Iwasawa, Nobuharu
-
supporting information
p. 17662 - 17665
(2015/12/18)
-
- Borylation using group IV metallocene under mild conditions
-
A borylation reaction of aromatic diazonium salts has been optimized using titanocene and zirconocene derivatives as catalysts. The reaction employs diisopropylaminoborane as a borylating agent and proceeds smoothly at room temperature to provide arylboronates after methanolysis and transesterification with pinacol. The reaction mechanism has been found to proceed via a radical pathway.
- Marciasini, Ludovic D.,Vaultier, Michel,Pucheault, Mathieu
-
supporting information
p. 1702 - 1705
(2014/03/21)
-
- NEW PROCESS FOR PREPARING ARYLBORANES BY ARYLATION OF ORGANOBORON COMPOUNDS
-
The present invention relates to a new process for the preparation of an arylborane compound, by arylation of a B-H bond, which comprises a step (1) of contacting an arenediazonium salt or a heteroarenediazonium salt with an organoboron compound containing at least one B-H bond, in a reaction medium containing a solvent, in the absence of base, in the absence or in the presence of an activating agent, for the preparation of an arylborane compound, and a possible step (2) of recovery and purification of said arylborane compound obtained at the step (1), said arylborane being in particular an aminoarylborane, and a possible step (3) of refunctionalisation of said arylborane obtained at step (1) or (2) for the preparation of aryl boronic derivatives or arylborates.
- -
-
Page/Page column 58
(2014/02/15)
-
- New process for preparing arylboranes by arylation of organoboron compounds
-
The present invention relates to a new process for the preparation of an arylborane compound, by arylation of a B-H bond, which comprises a step (1) of contacting an arenediazonium salt or a heteroarenediazonium salt with an organoboron compound containing at least one B-H bond, in a reaction medium containing a solvent, in the absence of base, in the absence or in the presence of an activating agent, for the preparation of an arylborane compound, and a possible step (2) of recovery and purification of said arylborane compound obtained at the step (1), said arylborane being in particular an aminoarylborane, and a possible step (3) of refunctionalisation of said arylborane obtained at step (1) or (2) for the preparation of aryl boronic derivatives or arylborates.
- -
-
Paragraph 0108; 0109; 0110; 0111; 0131; 0132
(2014/01/23)
-
- A solid chelating ligand: Periodic mesoporous organosilica containing 2,2′-bipyridine within the pore walls
-
Synthesis of a solid chelating ligand for the formation of efficient heterogeneous catalysts is highly desired in the fields of organic transformation and solar energy conversion. Here, we report the surfactant-directed self-assembly of a novel periodic mesoporous organosilica (PMO) containing 2,2′-bipyridine (bpy) ligands within the framework (BPy-PMO) from a newly synthesized organosilane precursor [(i-PrO) 3Si-C10H6N2-Si(Oi-Pr)3] without addition of any other silane precursors. BPy-PMO had a unique pore-wall structure in which bipyridine groups were densely and regularly packed and exposed on the surface. The high coordination ability to metals was also preserved. Various bipyridine-based metal complexes were prepared using BPy-PMO as a solid chelating ligand such as Ru(bpy)2(BPy-PMO), Ir(ppy) 2(BPy-PMO) (ppy = 2-phenylpyridine), Ir(cod)(OMe)(BPy-PMO) (cod = 1,5-cyclooctadiene), Re(CO)3Cl(BPy-PMO), and Pd(OAc) 2(BPy-PMO). BPy-PMO showed excellent ligand properties for heterogeneous Ir-catalyzed direct C-H borylation of arenes, resulting in superior activity, durability, and recyclability to the homogeneous analogous Ir catalyst. An efficient photocatalytic hydrogen evolution system was also constructed by integration of a Ru-complex as a photosensitizer and platinum as a catalyst on the pore surface of BPy-PMO without any electron relay molecules. These results demonstrate the great potential of BPy-PMO as a solid chelating ligand and a useful integration platform for construction of efficient molecular-based heterogeneous catalysis systems.
- Waki, Minoru,Maegawa, Yoshifumi,Hara, Kenji,Goto, Yasutomo,Shirai, Soichi,Yamada, Yuri,Mizoshita, Norihiro,Tani, Takao,Chun, Wang-Jae,Muratsugu, Satoshi,Tada, Mizuki,Fukuoka, Atsushi,Inagaki, Shinji
-
supporting information
p. 4003 - 4011
(2014/04/03)
-
- Iron-catalysed borylation of arenediazonium salts to give access to arylboron derivatives via aryl(amino)boranes at room temperature
-
Complementary to previously described Miyaura borylation methods, a new access to boron derivatives via aryl(amino)boranes is described. Direct coupling between aryldiazonium salts and diisopropylaminoborane is catalysed by 0.1% ferrocene leading to the formation of a carbon-boron bond. The obtained aryl(amino)boranes could eventually then be transformed into boronic acids, boronates or borates. Copyright
- Marciasini, Ludovic D.,Richy, Nicolas,Vaultier, Michel,Pucheault, Mathieu
-
supporting information
p. 1083 - 1088
(2013/05/21)
-
- Syntheses of (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)arenes through Pd-catalyzed borylation of arylbromides with the successive use of 2,2′-bis(1,3,2-benzodioxaborole) and pinacol
-
Syntheses of (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)arenes through the Pd-catalyzed borylation of arylbromides with the successive use of 2,2′-bis(1,3,2-benzodioxaborole) and pinacol were investigated. PdCl 2(dppf) and AcOK in EtOH or DMSO successfully provided (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)arenes. In particular, this method was more effective in the borylation of arylbromides bearing sulfonyl groups than the conventional Pd-catalyzed borylation using pinacolborane or bis(pinacolato)diboron.
- Takagi, Jun,Yamakawa, Tetsu
-
p. 166 - 169
(2013/02/21)
-
- Sterically controlled alkylation of arenes through iridium-catalyzed C-H borylation
-
Complementary chemistry: A one-pot method for the site-selective alkylation of arenes controlled by steric effects is reported. The process occurs through Ir-catalyzed C-H borylation, followed by Pd- or Ni-catalyzed coupling with alkyl electrophiles. This selectivity complements that of the typical Friedel-Crafts alkylation; meta-selective alkylation of a broad range of arenes with various electronic properties and functional groups occurs in good yield with high site selectivity. Copyright
- Robbins, Daniel W.,Hartwig, John F.
-
supporting information
p. 933 - 937
(2013/02/25)
-
- Sterically controlled iodination of arenes via iridium-catalyzed C-H borylation
-
A mild method to prepare aryl and heteroaryl iodides by sequential C-H borylation and iodination is reported. The regioselectivity of this process is controlled by steric effects on the C-H borylation step and is complementary to existing methods to form aryl iodides. The iodination of boronic esters has potential for the synthesis of radiolabeled aryl iodides, as demonstrated by the concise synthesis of a potential tracer for SPECT imaging.
- Partridge, Benjamin M.,Hartwig, John F.
-
supporting information
p. 140 - 143
(2013/03/28)
-
- Copper-catalyzed amination of arylboronates with N,N-dialkylhydroxylamines
-
A tolerant coupling: The title reaction has been developed to deliver arylamines (see scheme; Bz=benzoyl, dppbz=1,2-bis(diphenylphosphino)benzene). The catalysis is based on electrophilic, umpolung amination and enables the use of secondary acyclic amines. Various functional groups are tolerated, thus opening up a new substrate class for the Chan-Lam-type coupling.
- Matsuda, Naoki,Hirano, Koji,Satoh, Tetsuya,Miura, Masahiro
-
supporting information; experimental part
p. 3642 - 3645
(2012/05/20)
-
- Continuous-Flow C-H borylation of arene derivatives
-
A new continuous-flow system for C-H borylation has been developed. An insoluble catalyst prepared from chloro(1,5-cyclooctadien)iridium(I) dimer and 2,2′-bipyridine-4,4′-dicarboxylic acid in the presence of bis(pinacolato)diboron exhibited high reactivity under continuous-flow processing without the loss of expensive iridium metal.
- Tagata, Tsuyoshi,Nishida, Mayumi,Nishida, Atsushi
-
experimental part
p. 1662 - 1666
(2010/09/15)
-
- Iridium complexes of CCC-pincer N-heterocyclic carbene ligands: Synthesis and catalytic C-H functionalization
-
A series of four meta-phenylene-bridged bis-benzimidazolium chlorides were synthesized as precursors to rigid, monoanionic, CCC-pincer N-heterocyclic carbene ligands. For ligands with mesityl, 3,5-xylyl, or 3,5-di-tert-butylphenyl side groups, reaction with [Ir(1,5-cyclooctadiene)Cl]2 in acetonitrile with either excess triethylamine or stoichiometric cesium fluoride as base gave neutral, iridium(III) pincer complexes of the formula Ir(CCC)HCl(MeCN), which were purified by chromatography on silica gel. Metalation failed under these conditions for a 2,6-diisopropylphenyl-substituted derivative. In combination with NaOtBu, these complexes form active catalysts for the acceptorless dehydrogenation of cyclooctane and for arene C-H borylation in neat arene solvent.
- Chianese, Anthony R.,Mo, Allen,Lampland, Nicole L.,Swartz, Raymond L.,Bremer, Paul T.
-
experimental part
p. 3019 - 3026
(2010/10/03)
-
- "One-pot" tandem C - H borylation/1,4-conjugate addition/reduction sequence
-
A microwave-assisted, one-pot, iridium-catalyzed aromatic C - H borylation/rhodium-catalyzed 1,4-conjugate addition sequence provides a highly robust protocol suitable for high-throughput array synthesis. Selective formation of either β-aryl-substituted ketones or the corresponding alcohols can be achieved in good overall yields by simple variation of the reaction conditions.
- Tajuddin, Hazmi,Shukla, Lena,Maxwell, Aoife C.,Marder, Todd B.,Steel, Patrick G.
-
supporting information; experimental part
p. 5700 - 5703
(2011/03/19)
-
- Getting the sterics just right: A five-coordinate iridium trisboryl complex that reacts with C-H bonds at room temperature
-
Five-coordinate boryl complexes relevant to Ir mediated C-H borylations have been synthesized, providing a glimpse of the most fundamental step in the catalytic cycle for the first time.
- Chotana, Ghayoor A.,Vanchura II, Britt A.,Tse, Man Kin,Staples, Richard J.,Maleczka Jr., Robert E.,Smith III, Milton R.
-
p. 5731 - 5733
(2010/01/31)
-
- A one-pot, single-solvent process for tandem, catalyzed C-H borylation-Suzuki-Miyaura cross-coupling sequences
-
Methyl tert-butyl ether is a suitable solvent for iridium-catalyzed C-H borylation followed, in the same pot, by palladium-catalyzed Suzuki-Miyaura cross-coupling sequences, giving high yields of biaryls. Georg Thieme Verlag Stuttgart.
- Harrisson, Peter,Morris, James,Steel, Patrick G.,Marder, Todd B.
-
experimental part
p. 147 - 150
(2009/05/30)
-
- Development of recyclable iridium catalyst for C-H borylation
-
Aromatic C-H borylation using [IrCl(COD)]2 and 2,2′-bipyridinedicarboxylic acids was studied. 2,2′-Bipyridine-4,4′-dicarboxylic acid was complexed with [IrCl(COD)]2 in the presence of bis(pinacolato)diboron. The resulting iridium catalyst could be readily separated from the reaction mixture by simple filtration, and the recovered catalyst under a nitrogen atmosphere was still active and could be reused more than 10 times.
- Tagata, Tsuyoshi,Nishida, Mayumi,Nishida, Atsushi
-
scheme or table
p. 6176 - 6179
(2009/12/26)
-
- Iridium-catalyzed preparation of silylboranes by silane borylation and their use in the catalytic borylation of arenes
-
Silylboranes are versatile reagents for transition metal-catalyzed reactions of unsaturated organic molecules. These reagents are typically prepared by the addition of a silyl lithium species to a boron electrophile. However, the need to generate anionic silane reagents limits the scope of silylboranes that can be readily obtained. Here, we describe the synthesis of trialkylsilylboranes by the borylation of silanes catalyzed by iridium complexes. The reaction of trialkylhydrosilanes with B2pin 2 catalyzed by the combination of [Ir(OMe)cod]2 and 4,4′-di-tert-butylbipyridine forms trialkylsilylboronic esters. In addition, we show that these trialkylsilylboranes serve as boron sources for the iridium-catalyzed borylation of aryl C-H bonds. In contrast to diboron reagents, the silylboranes react with methylarenes at both the aryl and methyl C-H bonds.
- Boebel, Timothy A.,Hartwig, John F.
-
p. 6013 - 6019
(2009/04/13)
-
- One-pot synthesis of arylboronic acids and aryl trifluoroborates by Ir-catalyzed borylation of arenes
-
(Chemical Equation Presented) The synthesis of arylboronic acids and aryl trifluoroborates in a one-pot sequence by Ir-calalyzed borylation of arenes is reported. To prepare the arylboronic acids, the Ir-catalyzed borylation is followed by oxidative cleavage of the boronic ester with NaIO4. To prepare the aryltrifluoroborate, the Ir-catalyzed borylation is followed by displacement of pinacol by KHF2. These two-step sequences give products that are more reactive toward subsequent chemistry than the initially formed pinacol boronates.
- Murphy, Jaclyn M.,Tzschucke, C. Christoph,Hartwig, John F.
-
p. 757 - 760
(2007/10/03)
-
- Meta halogenation of 1,3-disubstituted arenes via iridium-catalyzed arene borylation
-
We report the meta halogenation of 1,3-disubstituted arenes to form 3,5-disubstituted aryl bromides and chlorides by using iridium-catalyzed arene borylation chemistry. Iridium-catalyzed borylation of arenes with B2pin2, followed by reaction of the boronic ester with copper(II) bromide or chloride converts arylboronic esters to the corresponding aryl halides. A variety of arenes containing alkoxy, alkyl, halogen, nitrile, ester, amide, and pivaloyl and TIPS-protected alcohols were converted to the corresponding 3,5-disubstituted aryl bromides and chlorides in yields ranging from 46% to 85%. In addition, 2,6-disubstituted and 3-substituted pyridines were converted to the 4-halo and 5-halopyridines, respectively. The utility of this methodology was demonstrated by the formal conversion of nicotine to Altinicline in three steps with an overall yield of 61% using meta bromination of nicotine as the first step. Copyright
- Murphy, Jaclyn M.,Liao, Xuebin,Hartwig, John F.
-
p. 15434 - 15435
(2008/09/19)
-
- Aromatic C-H borylation catalyzed by hydrotris(pyrazolyl)borate complexes of rhodium and iridium
-
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.
- Murata, Miki,Odajima, Hiroki,Watanabe, Shinji,Masuda, Yuzuru
-
p. 1980 - 1982
(2008/02/02)
-
- Mechanism of the mild functionalization of arenes by diboron reagents catalyzed by iridium complexes. Intermediacy and chemistry of bipyridine-ligated iridium trisboryl complexes
-
This paper describes mechanistic studies on the functionalization of arenes with the diboron reagent B2pin2 (bis-pinacolato diborane(4)) catalyzed by the combination of 4,4′-di-tert-butylbipyridine (dtbpy) and olefin-ligated iridium halide or olefin-ligated iridium alkoxide complexes. This work identifies the catalyst resting state as [Ir(dtbpy)(COE)(Bpin)3] (COE = cyclooctene, Bpin = 4,4,5,5-tetramethyl-1,3,2-dioxaborolanyl). [Ir(dtbpy)(COE)(Bpin)3] was prepared by independent synthesis in high yield from [Ir(COD)(OMe)] 2, dtbpy, COE, and HBpin. This complex is formed in low yield from [Ir(COD)(OMe)]2, dtbpy, COE, and B2pin2. Kinetic studies show that this complex reacts with arenes after reversible dissociation of COE. An alternative mechanism in which the arene reacts with the Ir(I) complex [Ir(dtbpy)Bpin] after dissociation of COE and reductive elimination of B2pin2 does not occur to a measurable extent. The reaction of [Ir(dtbpy)(COE)(Bpin)3] with arenes and the catalytic reaction of B2pin2 with arenes catalyzed by [Ir(COD)(OMe)]2 and dtbpy occur faster with electron-poor arenes than with electron-rich arenes. However, both the stoichiometric and catalytic reactions also occur faster with the electron-rich heteroarenes thiophene and furan than with arenes, perhaps because η2-heteroarene complexes are more stable than the η2-arene complexes and the η2-heteroarene or arene complexes are intermediates that precede oxidative addition. Kinetic studies on the catalytic reaction show that [Ir(dtbpy)(COE)(Bpin)3] enters the catalytic cycle by dissociation of COE, and a comparison of the kinetic isotope effects of the catalytic and stoichiometric reactions shows that the reactive intermediate [Ir(dtbpy)(Bpin)3] cleaves the arene C-H bond. The barriers for ligand exchange and C-H activation allow an experimental assessment of several conclusions drawn from computational work. Most generally, our results corroborate the conclusion that C-H bond cleavage is turnover-limiting, but the experimental barrier for this bond cleavage is much lower than the calculated barrier.
- Boller, Timothy M.,Murphy, Jaclyn M.,Hapke, Marko,Ishiyama, Tatsuo,Miyaura, Norio,Hartwig, John F.
-
p. 14263 - 14278
(2007/10/03)
-
- Aromatic C-H borylation catalyzed by iridium/2,6-diisopropyl-N-(2- pyridylmethylene)aniline complex
-
The C-H borylation of aromatic and heteroaromatic compounds, such as benzene, 1,3-dichlorobenzene, 1,3-bis(trifluoromethyl)benzene, 2,6-dichloropyridine, indole, benzothiophene and benzofuran, by bis(pinacolato)diboron or pinacolborane was catalyzed by a 1/2 [IrCl(COD)] 2-2,6-diisopropyl-N-(2-pyridylmethylene)aniline complex. The isopropyl groups of the ligand are essential for obtaining the products in high yield. Octane was a suitable solvent for the reactions of the above compounds except for indole. In the case of indole, DME was better than octane and the yield tended to improve with a smaller amount of the catalyst.
- Tagata, Tsuyosi,Nishida, Mayumi
-
p. 1655 - 1660
(2007/10/03)
-
- Process for the synthesis of phenols from arenes
-
A process to synthesize substituted phenols such as those of the general formula RR′R″Ar(OH) wherein R, R′, and R″ are each independently hydrogen or any group which does not interfere in the process for synthesizing the substituted phenol including, but not limited to, halo, alkyl, alkoxy, carboxylic ester, amine, amide; and Ar is any variety of aryl or hetroaryl by means of oxidation of substituted arylboronic esters is described. In particular, a metal-catalyzed C—H activation/borylation reaction is described, which when followed by direct oxidation in a single or separate reaction vessel affords phenols without the need for any intermediate manipulations. More particularly, a process wherein Ir-catalyzed borylation of arenes using pinacolborane (HBPin) followed by oxidation of the intermediate arylboronic ester by OXONE is described.
- -
-
-
- Regioselective aromatic borylation in an inert solvent.
-
[reaction: see text]. A protocol for performing Rh catalyzed aromatic borylations in cyclohexane has been devised. Borylation at the 5-position of several 1,3-substituted aromatic species ranging from electron-rich (1,3-(NMe(2))(2)C(6)H(4)) to electron-deficient (1,3-(CF(3))(2)C(6)H(4)) yields the corresponding aryl boronate esters. Veratrole was selectively borylated at the 4-position, thus extending regioselectivity to 1,2-substituted benzenes. Selective borylation at the 3-position of an N-protected pyrrole has also been demonstrated, providing a valuable reagent for cross-coupling reactions in a single step.
- Tse,Cho,Smith 3rd.
-
p. 2831 - 2833
(2007/10/03)
-