68716-51-8Relevant articles and documents
Understanding the Activation of Air-Stable Ir(COD)(Phen)Cl Precatalyst for C-H Borylation of Aromatics and Heteroaromatics
Slack, Eric D.,Colacot, Thomas J.
supporting information, p. 1561 - 1565 (2021/02/20)
A newly developed robust catalyst [Ir(COD)(Phen)Cl] (A) was used for the C-H borylation of three dozen aromatics and heteroaromatics with excellent yield and selectivity. Activation of the catalyst was identified by the use of catalytic amounts of water, alcohols, etc., when B2pin2 was used in noncoordinating solvents, while for THF catalytic use of HBpin was required. The results were on par with the in situ based expensive system [Ir(OMe)(COD)]2/dtbbpy or Me4Phen.
Direct C?H Borylation of Arenes Catalyzed by Saturated Hydride-Boryl-Iridium-POP Complexes: Kinetic Analysis of the Elemental Steps
Esteruelas, Miguel A.,Martínez, Antonio,Oliván, Montserrat,O?ate, Enrique
supporting information, p. 12632 - 12644 (2020/09/09)
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.
Highly Selective and Divergent Acyl and Aryl Cross-Couplings of Amides via Ir-Catalyzed C-H Borylation/N-C(O) Activation
Gao, Pengcheng,Szostak, Michal
supporting information, p. 6010 - 6015 (2020/07/30)
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.
meta-Nitration of Arenes Bearing ortho/para Directing Group(s) Using C?H Borylation
Li, Xuejing,Deng, Xingwang,Coyne, Anthony G.,Srinivasan, Rajavel
supporting information, p. 8018 - 8023 (2019/05/29)
Herein, we report the meta-nitration of arenes bearing ortho/para directing group(s) using the iridium-catalyzed C?H borylation reaction followed by a newly developed copper(II)-catalyzed transformation of the crude aryl pinacol boronate esters into the corresponding nitroarenes in a one-pot fashion. This protocol allows the synthesis of meta-nitrated arenes that are tedious to prepare or require multistep synthesis using the existing methods. The reaction tolerates a wide array of ortho/para-directing groups, such as ?F, ?Cl, ?Br, ?CH3, ?Et, ?iPr ?OCH3, and ?OCF3. It also provides regioselective access to the nitro derivatives of π-electron-deficient heterocycles, such as pyridine and quinoline derivatives. The application of this method is demonstrated in the late-stage modification of complex molecules and also in the gram-scale preparation of an intermediate en route to the FDA-approved drug Nilotinib. Finally, we have shown that the nitro product obtained by this strategy can also be directly converted to the aniline or hindered amine through Baran's amination protocol.
Sterically controlled C-H/C-H homocoupling of arenes: Via C-H borylation
Pei, Xiaocong,Zhou, Guan,Li, Xuejing,Xu, Yuchen,Panicker, Resmi C.,Srinivasan, Rajavel
supporting information, p. 5703 - 5707 (2019/06/19)
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.
METHODS OF MANUFACTURING OF BORON COMPOUND WITHOUT TRANSITION METALS
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Paragraph 0062; 0063; 0071; 0072; 0076, (2018/05/03)
The present invention refers to aryl boron compound number bath method relates to search, more particularly transition metal catalyst to a tank without the use of boron compounds number is given to the aryl organic halo [ceyn [ceyn] freight method are disclosed to boron. (by machine translation)
Highly active, separable and recyclable bipyridine iridium catalysts for C-H borylation reactions
Mamlouk, Hind,Suriboot, Jakkrit,Manyam, Praveen Kumar,Alyazidi, Ahmed,Bergbreiter, David E.,Madrahimov, Sherzod T.
, p. 124 - 127 (2018/01/17)
Iridium complexes generated from Ir(i) precursors and PIB oligomer functionalized bpy ligands efficiently catalyzed the reactions of arenes with bis(pinacolato)diboron under mild conditions to produce a variety of arylboronate compounds. The activity of this PIB bound homogeneous catalyst is similar to that of an original non-recyclable catalyst which allows it to be used under milder conditions than other reported recyclable catalysts. This oligomer-supported Ir catalyst was successfully recovered through biphasic extraction and reused for eight cycles without a loss of activity. Biphasic separation after the initial use of the catalyst led to an insignificant amount of iridium leaching from the catalyst to the product, and no iridium leaching from the catalyst was observed in the subsequent recycling runs. Arylboronate products obtained after extraction are sufficiently pure as observed by 1H and 13C-NMR spectroscopy that they do not require further purification.
Control Interlayer Stacking and Chemical Stability of Two-Dimensional Covalent Organic Frameworks via Steric Tuning
Wu, Xiaowei,Han, Xing,Liu, Yuhao,Liu, Yan,Cui, Yong
supporting information, p. 16124 - 16133 (2018/11/23)
Layer stacking and chemical stability are crucial for two-dimensional covalent organic frameworks (2D COFs), but are yet challenging to gain control. In this work, we demonstrate synthetic control of both the layer stacking and chemical stability of 2D COFs by managing interlayer steric hindrance via a multivariate (MTV) approach. By co-condensation of triamines with and without alkyl substituents (ethyl and isopropyl) and a di- or trialdehyde, a family of two-, three-, and four-component 2D COFs with AA, AB, or ABC stacking is prepared. The alkyl groups are periodically appended on the channel walls and their contents, which can be synthetically tuned by the MTV strategy, control the stacking model and chemical stability of 2D COFs by maximizing the total crystal stacking energy and protecting hydrolytically susceptible backbones through kinetic blocking. Specifically, the COFs with higher concentration of alkyl substituents adopt AB or ABC stacking, while lower amount of functionalities leads to the AA stacking. The COFs bearing high concentration of isopropyl groups represent the first identified COFs that can retain crystallinity and porosity in boiling 20 M NaOH solution. After postsynthetic metalation with an iridium complex, the 2,2′-bipyridyl-derived COFs can heterogeneously catalyze C-H borylation of arenes, whereas the COF with isopropyl groups exhibits much higher activity than the COFs with ethyl groups and nonsubstituents due to the increased porosity and chemical stability. This work underscores the opportunity in using steric hindrance to tune and control layer stacking, chemical stability and properties of 2D COFs.
Palladium-Catalyzed Synthesis of 2,3-Diaryl- N-methylindoles from ortho-Alkynylanilines and Aryl Pinacol Boronic Esters
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)
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
Chemoselective coupling of 1,1-bis[(pinacolato)boryl]alkanes for the transition-metal-frec borylation of aryl and vinyl halides: A combined experimental and theoretical investigation
Lee, Yeosan,Baek, Seung-Yeol,Park, Jinyoung,Kim, Seoung-Tae,Tussupbayev, Samat,Kim, Jeongho,Baik, Mu-Hyun,Cho, Seung Hwan
, p. 975 - 984 (2017/05/16)
A new transition-metal-frec borylation of aryl and vinyl halides using l,l-bis[(pinacolato)boryl]alkanes as boron sources is described. In this transformation one of the boron groups from 1,1-bis[(pinacolato)boryl]alkanes is selectively transferred to aryl and vinyl halides in the presence of sodium tert-butoxide as the only activator to form organoboronate esters. Under the developed borylation conditions, a broad range of organohalides are borylated with excellent chemo-selectivity and functional group compatibility, thus offering a rare example of a transition-metal-frec borylation protocol. Experimental and theoretical studies have becn performed to elucidate the reaction mechanism, revealing the unusual formation of Lewis acid/base adduct betwecn organohalides and α-borylcarbanion, generated in situ from the reaction of l,l-bis[(pinacolato)boryl]alkanes with an alkoxide base, to facilitate the borylation reactions.
