159087-45-3Relevant articles and documents
Substituent effects in Carboni-Lindsey reactions of 1,2,4,5-tetrazines and aryl-substituted alkynylboronates
Helm, Matthew D.,Plant, Andrew,Harrity, Joseph P. A.
, p. 2885 - 2887 (2007)
Evidence for an inverse-electron-demand cycloaddition of tetrazines with alkynylboronates is presented by the reaction of 3,6-bis(3,5-dimethyl-1H- pyrazol-1-yl)-1,2,4,5-tetrazine with aryl-alkynylboronate substrates bearing various para substituents. Geor
Copper-Catalyzed Triboration of Terminal Alkynes Using B2pin2: Efficient Synthesis of 1,1,2-Triborylalkenes
Liu, Xiaocui,Ming, Wenbo,Friedrich, Alexandra,Kerner, Florian,Marder, Todd B.
, p. 304 - 309 (2020)
We report herein the catalytic triboration of terminal alkynes with B2pin2 (bis(pinacolato)diboron) using readily available Cu(OAc)2 and PnBu3. Various 1,1,2-triborylalkenes, a class of compounds that have been demonstrated to be potential matrix metalloproteinase (MMP-2) inhibitors, were obtained directly in moderate to good yields. The process features mild reaction conditions, a broad substrate scope, and good functional group tolerance. This copper-catalyzed reaction can be conducted on a gram scale to produce the corresponding 1,1,2-triborylalkenes in modest yields. The utility of these products was demonstrated by further transformations of the C?B bonds to prepare gem-dihaloborylalkenes (F, Cl, Br), monohaloborylalkenes (Cl, Br), and trans-diaryldiborylalkenes, which serve as important synthons and have previously been challenging to prepare.
Aluminium-Catalyzed C(sp)?H Borylation of Alkynes
Willcox, Dominic R.,De Rosa, Daniel M.,Howley, Jack,Levy, Abigail,Steven, Alan,Nichol, Gary S.,Morrison, Carole A.,Cowley, Michael J.,Thomas, Stephen P.
supporting information, p. 20672 - 20677 (2021/08/20)
Historically used in stoichiometric hydroalumination chemistry, recent advances have transformed aluminium hydrides into versatile catalysts for the hydroboration of unsaturated multiple bonds. This catalytic ability is founded on the defining reactivity of aluminium hydrides with alkynes and alkenes: 1,2-hydroalumination of the unsaturated π-system. This manuscript reports the aluminium hydride catalyzed dehydroborylation of terminal alkynes. A tethered intramolecular amine ligand controls reactivity at the aluminium hydride centre, switching off hydroalumination and instead enabling selective reactions at the alkyne C?H σ-bond. Chemoselective C?H borylation was observed across a series of aryl- and alkyl-substituted alkynes (21 examples). On the basis of kinetic and density functional theory studies, a mechanism in which C?H borylation proceeds by σ-bond metathesis between pinacolborane (HBpin) and alkynyl aluminium intermediates is proposed.
Method for removing hydroboration of aluminum chloride catalytic terminal group alkyne
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Paragraph 0016-0018, (2021/10/16)
The invention discloses a hydroboration method of an aluminum chloride catalytic terminal group alkyne, and belongs to the technical field of boronation of terminal alkynes. To the method, the terminal group alkyne is added into the aluminum chloride with
ZnBr2-Catalyzed Dehydrogenative Borylation of Terminal Alkynes
Luo, Man,Qin, Yi,Chen, Xi,Xiao, Qian,Zhao, Binlin,Yao, Weiwei,Ma, Mengtao
, p. 16666 - 16674 (2021/11/18)
The simple, commercially available ZnBr2 has been successfully employed as a highly efficient and chemoselective catalyst for the dehydrogenative borylation of terminal alkynes with HBpin under mild conditions. It shows a good tolerance toward various functional groups such as aryl, alkyl, heteroaryl, etc. The plausible reaction mechanism has been investigated based on the corresponding stoichiometric experiments and DFT calculations.
Boron Recycling in the Metal-Free Transfer C-H Borylation of Terminal Alkynes and Heteroarenes
Desrosiers, Vincent,Fontaine, Frédéric-Georges,Garcia, Cecilia Zavaleta
, p. 11046 - 11056 (2020/11/23)
Transfer C-H borylation is an isodesmic approach to the borylation reaction using B-C-containing molecules as boron sources. In this work, we report that 2-mercaptothiazole and other analogues are active for the metal-free borylation of heterocycles and t
Photoredox-Mediated Reaction of gem-Diborylalkenes: Reactivity Toward Diverse 1,1-Bisborylalkanes
Eghbarieh, Nadim,Kumar, Nivesh,Masarwa, Ahmad,Shames, Alexander I.,Stein, Tamar
supporting information, p. 5360 - 5364 (2020/04/23)
The use of gem-diborylalkenes as radical-reactive groups is explored for the first time. These reactions provide an efficient and general method for the photochemical conversion of gem-diborylalkenes to rapidly access 1,1-bisborylalkanes. This method expl
Oxidation of Alkynyl Boronates to Carboxylic Acids, Esters, and Amides
Li, Chenchen,Li, Ruoling,Zhang, Bing,Zhao, Pei,Zhao, Wanxiang
supporting information, p. 10913 - 10917 (2020/05/25)
A general efficient protocol was developed for the synthesis of carboxylic acids, esters, and amides through oxidation of alkynyl boronates, generated directly from terminal alkynes. This protocol represents the first example of C(sp)?B bond oxidation. This approach displays a broad substrate scope, including aryl and alkyl alkynes, and exhibits excellent functional group tolerance. Water, primary and secondary alcohols, and amines are suitable nucleophiles for this transformation. Notably, amino acids and peptides can be used as nucleophiles, providing an efficient method for the synthesis and modification of peptides. The practicability of this methodology was further highlighted by the preparation of pharmaceutical molecules.
Divergent and Stereoselective Synthesis of Tetraarylethylenes from Vinylboronates
Stang, Peter J.,Yao, Yisen,Zhang, Minghao,Zhao, Wanxiang
supporting information, p. 20090 - 20098 (2020/09/02)
The synthesis of a new tetraborylethylene (TBE) is reported, and its application in the preparation of [4+0]-tetraarylethenes (TAEs) is elucidated. TAEs have widespread applications in material science and supramolecular chemistry due to their aggregation-induced emission (AIE) properties. The divergent and stereoselective synthesis of [3+1]-, [2+2]-, and [2+1+1]-TAEs via multiple couplings of vinylboronates with aryl bromides is demonstrated. These couplings feature a broad substrate scope and excellent functional group compatibility due to mild reaction conditions. Facile access to various tetraarylethenes is provided. This strategy represents an important complement to the conventional methods employed for the synthesis of TAEs, and would be a valuable tool for synthesizing TAE-based molecules useful in functional materials, biological imaging and chemical sensing.
Low-Coordinate NHC-Zinc Hydride Complexes Catalyze Alkyne C-H Borylation and Hydroboration Using Pinacolborane
Procter, Richard J.,Uzelac, Marina,Cid, Jessica,Rushworth, Philip J.,Ingleson, Michael J.
, p. 5760 - 5771 (2019/06/07)
Organozinc compounds containing sp, sp2, and sp3 C-Zn moieties undergo transmetalation with pinacolborane (HBPin) to produce Zn-H species and organoboronate esters (RBPin). This Zn-C/H-B metathesis step is key to enabling zinc-cataly
