1065498-70-5Relevant academic research and scientific papers
CuII-catalyzed regioselective borylation of alkynes and alkenes
Liu, Shiwen,Zeng, Xiaojun,Xu, Bo
, p. 3706 - 3710 (2016)
We developed a regioselective borylation of alkynes and alkenes protocol based on air-stable CuII/multi-dentate ligand system. Our catalytic system gives exclusive β-borylation products for most substrates in excellent chemical yields. We propo
Highly Selective Hydroboration of Terminal Alkenes Catalyzed by a Cobalt Pincer Complex Featuring a Central Reactive N-Heterocyclic Phosphido Fragment
Poitras, Andrew M.,Oliemuller, Leah K.,Hatzis, Gregory P.,Thomas, Christine M.
, p. 1025 - 1031 (2021)
The application of a cobalt pincer complex, (PPClP)CoCl2, as a precatalyst for the hydroboration of terminal alkenes with pinacolborane (HBPin) is described. The reactions proceed rapidly under mild conditions (room temperature, 30 min) with low catalyst
4-Cyanopyridine-catalyzed anti-Markovnikov selective hydroboration of alkenes
Xu, Rui,Lu, Guo-Ping,Cai, Chun
, p. 16456 - 16459 (2018)
A highly selective anti-Markovnikov hydroboration reaction of alkenes with bis(pinacolato)diboron catalyzed by 4-cyanopyridine has been described. This strategy provides an efficient, practical and environmentally benign protocol for the construction of alkylboronates in moderate to good yields under metal-free conditions. A radical mechanism proceeding via a 4-cyanopyridine-ligated boryl radical was proposed.
Base-free nickel-catalyzed hydroboration of simple alkenes with bis(pinacolato)diboron in an alcoholic solvent
Li, Jiang-Fei,Wei, Zhen-Zhong,Wang, Yong-Qiu,Ye, Mengchun
, p. 4498 - 4502 (2017)
A base-free nickel-catalyzed hydroboration of unreactive simple alkenes with bis(pinacolato)diboron using methanol as the hydride source under mild conditions has been developed. Methanol as the solvent proved to be critical for the base-free conditions and high reactivity. A series of linear alkylboronates were synthesized in moderate to excellent yields with high regioselectivity.
Hydroboration of terminal olefins with pinacolborane catalyzed by new 2-iminopyrrolyl iron(ii) complexes
Cruz, Tiago F. C.,Pereira, Laura C. J.,Waerenborgh, Jo?o C.,Veiros, Luís F.,Gomes, Pedro T.
, p. 3347 - 3360 (2019)
Four paramagnetic 14-electron tetracoordinated Fe(ii) complexes of 5-substituted-2-iminopyrrolyl ligands of the type [Fe{κ2N,N′-5-R-NC4H2-2-C(H)N(2,6-iPr2-C6H3)}(Py)Cl], with R = 2,6-Me2-C6H3 (1a), 2,4,6-iPr3-C6H2 (1b), 2,4,6-Ph3-C6H3 (1c) and CPh3 (1d), were synthesized in moderate yields by reacting the respective 5-substituted-2-iminopyrrolyl potassium salts KLa-d with FeCl2(Py)4 in toluene. Complexes 1a-d were characterized by 1H NMR, FTIR spectroscopies, elemental analysis and by the Evans method, the corresponding effective magnetic moments showing a high-spin electronic nature. X-ray diffraction studies on complexes 1a and 1c showed distorted tetrahedral coordination geometries. Complexes 1a-c, activated with K(HBEt3), were efficient catalyst systems for the hydroboration of several terminal alkenes with pinacolborane in good to high yields (50-90%). This system mainly yielded the respective anti-Markovnikov addition products, except when styrenes were used. A screening of the hydroboration of styrene catalyzed by complexes 1a-c activated with K(HBEt3) showed that the selectivity in the Markovnikov product increased with increasing steric bulkiness of the R group, exhibiting selectivities up to 91%. Additionally, the stoichiometric reaction of complex 1b with K(HBEt3) over 30 minutes yielded the mixture of hydride species 2 and 22 (mixture I). On the other hand, when reacting the same components over 16 h, the Fe(i) complex 3 was also identified in the mixture, in addition to 2 + 22 (mixture II). These mixtures were characterized in solution by the Evans method and in the solid state by elemental analysis, 57Fe M?ssbauer and FTIR spectroscopies, compounds 22 and 3 being also analyzed by X-ray diffraction. These results suggest that the corresponding catalytic cycle follows the borane oxidative addition route to a Fe(i) species.
Ni-catalyzed hydroboration and hydrosilylation of olefins with diboron and silylborane
Kamei, Toshiyuki,Nishino, Sohshi,Shimada, Toyoshi
, p. 2896 - 2899 (2018)
Herein we report a Ni-catalyzed formal hydroboration of olefins, which afforded anti-Markovnikov-type alkylboranes with B2pin2 and a stoichiometric amount of water. Formal hydrosilylation using air- and moisture-sensitive silylborane
Markovnikov-Selective Hydroboration of Vinylarenes Catalyzed by a Cobalt(II) Coordination Polymer
Zhang, Guoqi,Wu, Jing,Li, Sihan,Cass, Sean,Zheng, Shengping
, p. 7893 - 7897 (2018)
Highly efficient and practical hydroboration of alkenes has been catalyzed by an inexpensive and air-stable cobalt(II) coordination polymer (CP) in the presence of KOtBu. Complete conversion of alkenes to alkylboronates were performed within just 5 min with low catalyst loading (0.025 mol%), achieving the record high turnover frequencies of up to 47 520 h-1. For a range of vinylarenes, unusual Markovnikov selectivity was observed.
Chromium-Catalyzed Borylative Coupling of Aliphatic Bromides with Pinacolborane by Hydrogen Evolution
Fu, Aiping,Li, Chao,Luo, Meiming,Zeng, Xiaoming,Zhao, Lixing
, p. 2204 - 2208 (2021)
The chromium-catalyzed borylative coupling between aliphatic bromides and pinacolborane (HBpin) is described. This reaction was promoted by low-cost and bench-stable CrCl3as a precatalyst combined with 4,4′-di-tert-butyl-2,2′-dipyridyl and aluminum, presenting a rare example of using HBpin as a borane reagent by coupling with alkyl bromides in forming borylated alkanes. Mechanistic studies indicate that aluminum plays important roles in the formation of reactive Cr species and aliphatic radicals, which lead to (alkyl)Cr by reaction with HBpin to give the products.
Hydroboration of Terminal Alkenes and trans-1,2-Diboration of Terminal Alkynes Catalyzed by a Manganese(I) Alkyl Complex
Kirchner, Karl,St?ger, Berthold,Veiros, Luis F.,Weber, Stefan,Zobernig, Daniel
, p. 24488 - 24492 (2021)
A MnI-catalyzed hydroboration of terminal alkenes and a 1,2-diboration of terminal alkynes with pinacolborane (HBPin) is described. For alkenes, anti-Markovnikov hydroboration takes place; for alkynes the reaction proceeds with excellent trans-1,2-selectivity. The most active pre-catalyst is bench-stable alkyl bisphosphine MnI complex fac-[Mn(dippe)(CO)3(CH2CH2CH3)]. The catalytic process is initiated by migratory insertion of a CO ligand into the Mn–alkyl bond to yield an acyl intermediate, which undergoes B?H bond cleavage of HBPin (for alkenes) and rapid C?H bond cleavage (for alkynes), forming the active MnI boryl and acetylide catalysts [Mn(dippe)(CO)2(BPin)] and [Mn(dippe)(CO)2(C≡CR)], respectively. A broad variety of aromatic and aliphatic alkenes and alkynes was efficiently and selectively borylated. Mechanistic insights are provided based on experimental data and DFT calculations revealing that an acceptorless reaction is operating involving dihydrogen release.
Borane-Catalysed Hydroboration of Alkynes and Alkenes
Ang, Nate W. J.,Buettner, Cornelia S.,Docherty, Scott,Bismuto, Alessandro,Carney, Jonathan R.,Docherty, Jamie H.,Cowley, Michael J.,Thomas, Stephen P.
, p. 803 - 808 (2018)
Simple, commercially available borane adducts, H 3 B·THF and H 3 B·SMe 2, have been used to catalyse the hydroboration of alkynes and alkenes with pinacolborane to give the alkenyl and alkyl boronic esters, respectively. A
