872356-95-1Relevant academic research and scientific papers
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 0028-0030, (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.
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
Iron-Catalyzed Dehydrogenative Borylation of Terminal Alkynes
Wei, Duo,Carboni, Bertrand,Sortais, Jean-Baptiste,Darcel, Christophe
supporting information, p. 3649 - 3654 (2018/09/14)
The catalytic system based on Fe(OTf)2 (2.5 mol%) and DABCO (1 mol%) selectively promotes the dehydrogenative borylation of both aromatic and aliphatic terminal alkynes to afford alkynylboronate derivatives in the presence of 1 equiv. of pinaco
The Pauson-Khand reaction using alkynylboronic esters: Solving a long-standing regioselectivity issue
León, Thierry,Fernández, Elena
supporting information, p. 9363 - 9366 (2016/07/29)
The first intermolecular Pauson-Khand reaction, conducted using internal alkynylboronic esters, allows the installation of the boronic ester moiety at the β-position of the cyclopentenone with total regio- and stereoselectivity.
Synthesis of Triborylalkenes from Terminal Alkynes by Iridium-Catalyzed Tandem C-H Borylation and Diboration
Lee, Chun-I,Shih, Wei-Chun,Zhou, Jia,Reibenspies, Joseph H.,Ozerov, Oleg V.
supporting information, p. 14003 - 14007 (2016/01/25)
A two-step reaction to convert terminal alkynes into triborylalkenes is reported. In the first step, the terminal alkyne and pinacolborane (HBpin) are converted into an alkynylboronate, which is catalyzed by an iridium complex supported by a SiNN pincer l
