167692-95-7Relevant articles and documents
Visible-Light-Mediated Decarboxylative Radical Additions to Vinyl Boronic Esters: Rapid Access to γ-Amino Boronic Esters
Noble, Adam,Mega, Riccardo S.,Pfl?sterer, Daniel,Myers, Eddie L.,Aggarwal, Varinder K.
, p. 2155 - 2159 (2018)
The synthesis of alkyl boronic esters by direct decarboxylative radical addition of carboxylic acids to vinyl boronic esters is described. The reaction proceeds under mild photoredox catalysis and involves an unprecedented single-electron reduction of an α-boryl radical intermediate to the corresponding anion. The reaction is amenable to a diverse range of substrates, including α-amino, α-oxy, and alkyl carboxylic acids, thus providing a novel method to rapidly access boron-containing molecules of potential biological importance.
Neosilyllithium-Catalyzed Hydroboration of Alkynes and Alkenes in the Presence of Pinacolborane (HBpin)
Kumar, Gobbilla Sai,Moorthy, Shruti,Karmakar, Himadri,Singh, Saurabh Kumar,Panda, Tarun K.
supporting information, (2021/11/13)
We report here a novel protocol for the hydroboration of alkynes and alkenes, which in the presence of neosilyllithium (LiCH2SiMe3) (5 mol %) and pinacolborane efficiently results in the formation of corresponding alkenyl and alkyl b
Site-Fixed Hydroboration of Terminal and Internal Alkenes using BX3/iPr2NEt**
Cui, Xin,Hu, Chenyang,Li, Sida,Liu, Liu Leo,Wu, Lipeng,Zhang, Jiong
supporting information, p. 26238 - 26245 (2021/11/09)
An unprecedented and general hydroboration of alkenes with BX3 (X=Br, Cl) as the boration reagent in the presence of iPr2NEt is reported. The addition of iPr2NEt not only suppresses alkene polymerizat
Transition metal- And light-free radical borylation of alkyl bromides and iodides using silane
Mo, Fanyang,Sun, Beiqi,Zheng, Sihan
supporting information, p. 5674 - 5677 (2021/06/16)
We report operationally simple and neutral conditions for borylation of alkyl bromides and iodides to alkyl boronic esters under transition metal- and light-free conditions. A series of substrates with a wide range of functional groups were effectively transformed into the borylation products in moderate to good yields. Mechanistic studies, including radical clock experiments and DFT calculations, gave detailed insight into the radical borylation process.
Method for directly preparing alkyl borate compound from alkyl halide
-
Paragraph 0124-0126, (2021/04/14)
The invention relates to a method for directly preparing an alkyl borate compound from an alkyl halide, which comprises the following steps: in a protective atmosphere, mixing a titanium metal catalyst, an alkali compound, a borate compound and an alkyl halide or sulfonate compound, reacting at 35-100 DEG C for 8-24 hours, so that the alkyl halide or sulfonate compound is directly converted into the alkyl boronic acid pinacol ester compound. The method is simple to operate, low in cost, good in functional group tolerance and wide in substrate application range.
Catalytic Boration of Alkyl Halides with Borane without Hydrodehalogenation Enabled by Titanium Catalyst
Wang, Xianjin,Cui, Penglei,Xia, Chungu,Wu, Lipeng
supporting information, p. 12298 - 12303 (2021/05/07)
An unprecedented and general titanium-catalyzed boration of alkyl (pseudo)halides (alkyl-X, X=I, Br, Cl, OMs) with borane (HBpin, HBcat) is reported. The use of titanium catalyst can successfully suppress the undesired hydrodehalogenation products that prevail using other transition-metal catalysts. A series of synthetically useful alkyl boronate esters are readily obtained from various (primary, secondary, and tertiary) alkyl electrophiles, including unactivated alkyl chlorides, with tolerance of other reducing functional groups such as ester, alkene, and carbamate. Preliminary studies on the mechanism revealed a possible radical reaction pathway. Further extension of our strategy to aryl bromides is also demonstrated.
Silver-Catalyzed Hydroboration of C-X (X = C, O, N) Multiple Bonds
Pandey, Vipin K.,Tiwari, Chandra Shekhar,Rit, Arnab
supporting information, p. 1681 - 1686 (2021/03/03)
AgSbF6 was developed as an effective catalyst for the hydroboration of various unsaturated functionalities (nitriles, alkenes, and aldehydes). This atom-economic chemoselective protocol works effectively under low catalyst loading, base- A nd solvent-free moderate conditions. Importantly, this process shows excellent functional group tolerance and compatibility with structurally and electronically diverse substrates (>50 examples). Mechanistic investigations revealed that the reaction proceeds via a radical pathway. Further, the obtained N,N-diborylamines were showcased to be useful precursors for amide synthesis.
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
supporting information, p. 24488 - 24492 (2021/10/19)
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.
Manganese-Catalyzed Hydroboration of Terminal Olefins and Metal-Dependent Selectivity in Internal Olefin Isomerization-Hydroboration
Garhwal, Subhash,Kroeger, Asja A.,Thenarukandiyil, Ranjeesh,Fridman, Natalia,Karton, Amir,De Ruiter, Graham
supporting information, p. 494 - 504 (2021/01/11)
In the past decade, the use of earth-abundant metals in homogeneous catalysis has flourished. In particular, metals such as cobalt and iron have been used extensively in reductive transformations including hydrogenation, hydroboration, and hydrosilylation
Synthesis and Catalytic Reactivity of Cobalt Pincer Nitrosyl Hydride Complexes
Pecak, Jan,Fleissner, Sarah,Veiros, Luis F.,Pittenauer, Ernst,St?ger, Berthold,Kirchner, Karl
, p. 278 - 285 (2021/02/03)
The synthesis, characterization, and catalytic activity of low-spin {CoNO}8 pincer complexes of the type [Co(PCP)(NO)(H)] are described. These compounds are obtained either by reacting [Co(PCP)(κ2-BH4)] with NO and Et3N or, alternatively, by reacting [Co(