251928-75-3Relevant academic research and scientific papers
Copper(ii)-catalyzed protoboration of allenes in aqueous media and open air
Nekvinda, Jan,Santos, Webster L.,Snead, Russell F.
, p. 14925 - 14931 (2021/09/04)
A method has been developed for the facile Cu(ii)-catalyzed protoboration of monosubstituted allenes in aqueous media under atmospheric conditions. The reaction occurs site selectively, favoring internal alkene protoboration to afford 1,1-disubstituted vinylboronic acid derivatives (up to 93?:?7) with modest to good yields. The method has been applied to a variety of phenylallene derivatives as well as alkyl-substituted allenes. This journal is
Electrochemical Hydroboration of Alkynes
Aelterman, Maude,Jubault, Philippe,Poisson, Thomas,Sayes, Morgane
supporting information, p. 8277 - 8282 (2021/05/27)
Herein we reported the electrochemical hydroboration of alkynes by using B2Pin2 as the boron source. This unprecedented reaction manifold was applied to a broad range of alkynes, giving the hydroboration products in good to excellent yields without the need of a metal catalyst or a hydride source. This transformation relied on the possible electrochemical oxidation of an in situ formed borate. This anodic oxidation performed in an undivided cell allowed the formation of a putative boryl radical, which reacted on the alkyne.
Cobalt-Catalyzed Markovnikov-Type Selective Hydroboration of Terminal Alkynes
Chen, Jieping,Shen, Xuzhong,Lu, Zhan
supporting information, p. 690 - 694 (2020/11/30)
A cobalt-catalyzed Markovnikov-type hydroboration of terminal alkynes with HBpin to access α-alkenyl boronates with good regioselectivity and atom economy is reported. A new ligand has been developed for the cobalt hydride catalyst that has been used for a unique Markovnikov selective insertion of terminal alkynes into metal hydride bond. This operationally simple protocol exhibits excellent functional group tolerance to deliver valuable alkene derivatives.
A 1, 1 - disubstituted [...] compound synthesis method
-
Paragraph 0027-0042, (2019/03/28)
The invention discloses a 1, 1 - disubstituted [...] compound synthesis method, the catalyst cuprous chloride, carbene precursor, the tertiary butyl alcohol potassium is added in the Schlenk reaction tube, vacuum, in an inert gas conditions, adding tetrahydrofuran, stir; then the [...][...], type I shown and methanol is dissolved in the tetrahydrofuran zincon after, in the Schlenk reaction tube of the instillment to states, for 25 °C stirring for 1 - 5 hours, the resulting reaction solution after treatment of formula II shown in 1, 1 - disubstituted [...] compound. Synthesis method of the invention has catalyst is cheap and easy to obtain and the low toxicity, high selectivity, environment friendly, mild reaction conditions, functional group universal good and simple operation and the like.
Copper-Catalyzed Triboration: Straightforward, Atom-Economical Synthesis of 1,1,1-Triborylalkanes from Terminal Alkynes and HBpin
Liu, Xiaocui,Ming, Wenbo,Zhang, Yixiao,Friedrich, Alexandra,Marder, Todd B.
, p. 18923 - 18927 (2019/11/22)
A convenient and efficient one-step synthesis of 1,1,1-triborylalkanes was achieved via sequential dehydrogenative borylation and double hydroborations of terminal alkynes with HBpin (HBpin=pinacolborane) catalyzed by inexpensive and readily available Cu(OAc)2. This process proceeds under mild conditions, furnishing 1,1,1-tris(boronates) with wide substrate scope, excellent selectivity, and good functional-group tolerance, and is applicable to gram-scale synthesis without loss of yield. The 1,1,1-triborylalkanes can be used in the preparation of α-vinylboronates and borylated cyclic compounds, which are valuable but previously rare compounds. Different alkyl groups can be introduced stepwise via base-mediated deborylative alkylation to produce racemic tertiary alkyl boronates, which can be readily transformed into useful tertiary alcohols.
Synthesis of Vinyl-, Allyl-, and 2-Boryl Allylboronates via a Highly Selective Copper-Catalyzed Borylation of Propargylic Alcohols
Mao, Lujia,Bertermann, Rüdiger,Emmert, Katharina,Szabó, Kálmán J.,Marder, Todd B.
, p. 6586 - 6589 (2017/12/26)
An efficient methodology for the synthesis of vinyl-, allyl-, and (E)-2-boryl allylboronates from propargylic alcohols via Cu-catalyzed borylation under mild conditions is reported. In the presence of commercially available Cu(OAc)2 or Cu(acac)2 and Xantphos, the reaction affords the desired products in up to 92% yield with a broad substrate scope (43 examples). Isolation of an allenyl boronate as the reaction intermediate suggests that an insertion-elimination-type reaction, followed by borylcupration, is involved in the borylation of propargylic alcohols.
Superparamagnetic copper ferrite nanoparticles catalyzed aerobic, ligand-Free, regioselective hydroboration of alkynes: Influence of synergistic effect
Mohan, Balaji,Park, Kang Hyun
, p. 78 - 84 (2016/04/05)
We discovered a general and comprehensive approach for the regioselective hydroboration of terminal and internal alkynes to synthesize vinylboronates using inexpensive and magnetically separable copper ferrite nanoparticles at low catalyst loading using Bis(pinacolato)diboron in the absence of ligand and additives, under mild and greener conditions. A diverse range of functional groups was tolerated in the reaction, including allene and enones, and the corresponding boronates were obtained in high yields under air. Moreover, the assynthesized alkenylboronates were used as precursors to prepare wide variety of vinylorgano chalcogenides regioselectively, in high yields. The present protocol enable the conversion of Csp-H bonds to make Csp2-B bonds via activation of B-B bond, followed by formation of Csp2-Se (Te or S) bonds via activation of Se (Te or S)- Se (Te or S) bonds in a regioselective manner. Deuterium isotope labeling studies showed that the proton source of vinyl boronate stem from the solvent employed.
Copper-catalyzed regioselective hydroboration of terminal alkynes in aqueous medium
Yao, Zi-Jian,Hong, Shibin,Zhang, Wei,Liu, Mengyan,Deng, Wei
supporting information, p. 910 - 913 (2016/02/05)
A mild and environment-friendly copper-catalyzed hydroboration of terminal alkynes in aqueous medium was reported. Regioselectivity control was achieved in the presence of cyclodextrin-bispyridine ligand (CD-1). This protocol was successfully applied to inactivated terminal alkynes. Moreover, the ligand was recovered and reused without any loss of activity over five cycles.
Silver-catalyzed highly regioselective formal hydroboration of alkynes
Yoshida, Hiroto,Kageyuki, Ikuo,Takaki, Ken
supporting information, p. 3512 - 3515 (2014/07/21)
A silver(I)-N-heterocyclic carbene complex has proven to be a potent catalyst for formal hydroboration of alkynes, providing a variety of borylalkenes in regio- and stereoselective manners. Under the silver catalysis, allenes also undergo regioselective hydroboration to give borylalkenes.
Formal regiocontrolled hydroboration of unbiased internal alkynes via borylation/allylic alkylation of terminal alkynes
Moure, Abraham L.,Mauleon, Pablo,Arrayas, Ramon Gomez,Carretero, Juan Carlos
supporting information, p. 2054 - 2057 (2013/06/04)
In accessing trisubstituted vinyl boronates from terminal alkynes, a propargyl directing (2-pyridyl)sulfonyl group allows terminal alkynes to undergo Cu-catalyzed B2(pin)2-borylation and subsequent Cu-catalyzed allylic alkylation wit
