1379610-52-2Relevant academic research and scientific papers
Undeniable Confirmation of the syn-Addition Mechanism for Metal-Free Diboration by Using the Crystalline Sponge Method
Cuenca, Ana B.,Zigon, Nicolas,Duplan, Vincent,Hoshino, Manabu,Fujita, Makoto,Fernández, Elena
, p. 4723 - 4726 (2016)
The stereochemical outcome of the recently developed metal-free 1,2-diboration of aliphatic alkenes has, until now, only been elucidated by indirect means (e.g. derivatization). This is because classical conformational analysis of the resulting 1,2-diboranes is not viable; in the 1H NMR spectrum the relevant 1H resonances are broadened by 11B, and the occurrence of the products as oily compounds precludes X-ray crystallographic analysis. Herein, the crystalline sponge method is used to display the crystal structures of the diboronic esters formed from internal E and Z olefins, evidencing the stereospecific syn addition mechanism of the reaction, which is fully consistent with the prediction from DFT calculations. The crystalline sponge method provides conclusive proof of the stereospecific addition in the metal-free diboration of internal aliphatic alkenes (see scheme). The compatibility of common boryl groups with a monoporous ZnI2 network gives access to the crystal structures of the oily organoborane compounds. The relative stereochemistry of the metal-free diboration products was unequivocally assigned and fully consistent with the DFT calculations.
An Olefinic 1,2-α-Boryl Migration Enables 1,2-Bis(boronic esters) via Radical-Polar Crossover Reaction
Zhang, Feng,Liao, Shangteng,Zhou, Lu,Yang, Kai,Wang, Chenglan,Lou, Yixian,Wang, Cece,Song, Qiuling
, p. 582 - 588 (2022/01/11)
A radical-induced 1,2-α-boryl migration through radical polar crossover reactions has been described. In this work, in situ formed vinyldiboron “ate” complexes from alkenyl Grignard reagent and diborylalkanes react with commercial radical precursors under light initiation. This three-component process enables diborylation of alkene. This protocol features high atom economy, a broad substrate scope as well as good functional group toleration with mild conditions.
Electrophilic Fluorination of Alkenes via Bora-Wagner–Meerwein Rearrangement. Access to β-Difluoroalkyl Boronates
Biosca, Maria,Himo, Fahmi,Szabó, Kálmán J.,Wang, Qiang
, p. 26327 - 26331 (2021/11/16)
The electrophilic fluorination of geminal alkyl substituted vinyl-Bmida derivatives proceeds via bora-Wagner–Meerwein rearrangement. According to DFT modelling studies this rearrangement occurs with a low activation barrier via a bora-cyclopropane shaped TS. The Bmida group has a larger migration aptitude than the alkyl moiety in the Wagner–Meerwein rearrangement of the presented electrophilic fluorination reactions.
Copper-Catalyzed Borylative Methylation of Alkyl Iodides with CO as the C1 Source: Advantaged by Faster Reaction of CuH over CuBpin
Wu, Fu-Peng,Wu, Xiao-Feng
supporting information, p. 11730 - 11734 (2021/04/22)
CuH and CuBpin are versatile catalysts and intermediates in organic chemistry. However, studies that involve both CuH and CuBpin in the same reaction is still rarely reported due to their high reactivity. Now, a study on CuH- and CuBpin-catalyzed borylative methylation of alkyl iodides with CO as the C1 source is reported. Various one carbon prolongated alkyl boranes (RCH2Bpin and RCH(Bpin)2) were produced in moderate to good yields from the corresponding alkyl iodides (RI). In this cooperative system, CuH reacts with alkyl iodide faster than CuBpin.
Method for preparation of gem-diboron compound by olefin selective 1, 1-diboronation
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Paragraph 0107-0108, (2020/06/17)
The invention relates to a method for preparation of a gem-diboron compound by olefin selective 1, 1-diboronation. The method includes: dissolving an olefin compound, a cyclopentadienyl early transition metal catalyst and an alkali compound in a solvent, then adding a borane compound, carrying out reaction at 60-150DEG C for 1-16h in a protective atmosphere, and then carrying out separation to obtain the gem-diboron compound. The method is simple and convenient to operate, low in cost, and high in reaction atom economy, and is suitable for industrial production.
Zirconium-Catalyzed Atom-Economical Synthesis of 1,1-Diborylalkanes from Terminal and Internal Alkenes
Cui, Xin,Jiao, Haijun,Li, Sida,Wang, Xianjin,Wang, Yue,Wu, Lipeng,Xia, Chungu
supporting information, p. 13608 - 13612 (2020/06/02)
A general and atom-economical synthesis of 1,1-diborylalkanes from alkenes and a borane without the need for an additional H2 acceptor is reported for the first time. The key to our success is the use of an earth-abundant zirconium-based catalyst, which allows a balance of self-contradictory reactivities (dehydrogenative boration and hydroboration) to be achieved. Our method avoids using an excess amount of another alkene as an H2 acceptor, which was required in other reported systems. Furthermore, substrates such as simple long-chain aliphatic alkenes that did not react before also underwent 1,1-diboration in our system. Significantly, the unprecedented 1,1-diboration of internal alkenes enabled the preparation of 1,1-diborylalkanes.
Photoredox-Mediated Reaction of gem-Diborylalkenes: Reactivity Toward Diverse 1,1-Bisborylalkanes
Eghbarieh, Nadim,Kumar, Nivesh,Masarwa, Ahmad,Shames, Alexander I.,Stein, Tamar
, 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
Selective C?C Coupling of Vinyl Epoxides with Diborylmethide Lithium Salts
Gava, Riccardo,Fernández, Elena
supporting information, p. 8013 - 8017 (2019/05/29)
Vinyl epoxides and styrene oxide can react with diborylmethide lithium salts through an exclusive SN2 borylmethylation/ring opening in a regio- and diastereoselective way, depending on the nature of the substrate. The ring-opening protocol prov
Diborylalkyllithium Salts Trigger Regioselective Ring Opening of Vinyl Aziridines
Salvado, Oriol,Gava, Riccardo,Fernández, Elena
supporting information, p. 9247 - 9250 (2019/11/14)
gem-Diborylalkanes treated with LiTMP produce α-diborylalkane lithium bases that perform nucleophilic attack on vinyl aziridines with controlled regioselectivity. Preferred SN2 diborylalkylation ring opening reaction on the less sterically hind
Preparation method and application of geminal diboron compound
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Paragraph 0040; 0041; 0042; 0044; 0045; 0046, (2019/05/22)
The invention discloses a preparation method and application of a geminal diboron compound. The preparation method includes: in a protective atmosphere, subjecting a uniform mixture system of a carbonyl compound, a diboron reagent, an iron catalyst, an alkaline substance, a proton source and a solvent to reaction at 60-150 DEG C for 3-36 h, and separating to obtain the geminal diboron compound. The preparation method herein constructs, in one step, the geminal diboron compound which is difficult to efficiently implement in the past, from simple, economical and easily accessible materials as substrates under catalyst of the iron catalyst; the geminal diboron compound has a good application prospect in the sciences of pharmaceutical synthetic intermediates and organic photoelectric materials; the preparation method herein helps solve the problem that the field of traditional preparation of geminal diboron compounds requires pre-functionalization or some substrates are incompatible; the reaction conditions are relatively mild; operation is simple; the raw materials are economical and easy to attain; the reaction efficiency is high; the preparation method herein provides good functional group compatibility.
