1008760-87-9Relevant academic research and scientific papers
Zinc-Catalyzed Dual C-X and C-H Borylation of Aryl Halides
Bose, Shubhankar Kumar,Deissenberger, Andrea,Eichhorn, Antonius,Steel, Patrick G.,Lin, Zhenyang,Marder, Todd B.
, p. 11843 - 11847 (2015)
A zinc-catalyzed combined C-X and C-H borylation of aryl halides using B2pin2 (pin=OCMe2CMe2O) to produce the corresponding 1,2-diborylarenes under mild conditions was developed. Catalytic C-H bond activation occurs ortho to the halide groups if such a site is available or meta to the halide if the ortho position is already substituted. This method thus represents a novel use of a groupXII catalyst for C-H borylation. This transformation does not proceed via a free aryne intermediate, but a radical process seems to be involved. Two B or not two B: A novel catalytic system based on a ZnII-dtbpy precursor was developed for the preparation of 1,2-diborylarenes. This method represents a new type of catalytic process for diborylation of aryl halides via both C-X and C-H activation.
Visible-Light-Induced Ni-Catalyzed Radical Borylation of Chloroarenes
Tian, Ya-Ming,Guo, Xiao-Ning,Krummenacher, Ivo,Wu, Zhu,Nitsch, J?rn,Braunschweig, Holger,Radius, Udo,Marder, Todd B.
supporting information, p. 18231 - 18242 (2020/11/02)
A highly selective and general photoinduced C-Cl borylation protocol that employs [Ni(IMes)2] (IMes = 1,3-dimesitylimidazoline-2-ylidene) for the radical borylation of chloroarenes is reported. This photoinduced system operates with visible light (400 nm) and achieves borylation of a wide range of chloroarenes with B2pin2 at room temperature in excellent yields and with high selectivity, thereby demonstrating its broad utility and functional group tolerance. Mechanistic investigations suggest that the borylation reactions proceed via a radical process. EPR studies demonstrate that [Ni(IMes)2] undergoes very fast chlorine atom abstraction from aryl chlorides to give [NiI(IMes)2Cl] and aryl radicals. Control experiments indicate that light promotes the reaction of [NiI(IMes)2Cl] with aryl chlorides generating additional aryl radicals and [NiII(IMes)2Cl2]. The aryl radicals react with an anionic sp2-sp3 diborane [B2pin2(OMe)]- formed from B2pin2 and KOMe to yield the corresponding borylation product and the [Bpin(OMe)]?- radical anion, which reduces [NiII(IMes)2Cl2] under irradiation to regenerate [NiI(IMes)2Cl] and [Ni(IMes)2] for the next catalytic cycle.
Platinum-catalysed diborylation of arynes: Synthesis and reaction of 1,2-diborylarenes
Yoshida, Hiroto,Okada, Kengo,Kawashima, Shota,Tanino, Kenji,Ohshita, Joji
supporting information; experimental part, p. 1763 - 1765 (2010/07/04)
Arynes are found to be facilely inserted into bis(pinacolato)diboron by using a platinum-isocyanide catalyst, affording diverse 1,2-diborylarenes, which can be converted into o-terphenyls via Suzuki-Miyaura coupling reaction.
