864772-18-9Relevant articles and documents
Photo-induced thiolate catalytic activation of inert Caryl-hetero bonds for radical borylation
K?nig, Burkhard,Wang, Hua,Wang, Shun
supporting information, p. 1653 - 1665 (2021/06/17)
Substantial effort is currently being devoted to obtaining photoredox catalysts with high redox power. Yet, it remains challenging to apply the currently established methods to the activation of bonds with high bond dissociation energy and to substrates with high reduction potentials. Herein, we introduce a novel photocatalytic strategy for the activation of inert substituted arenes for aryl borylation by using thiolate as a catalyst. This catalytic system exhibits strong reducing ability and engages non-activated Caryl–F, Caryl–X, Caryl–O, Caryl–N, and Caryl–S bonds in productive radical borylation reactions, thus expanding the available aryl radical precursor scope. Despite its high reducing power, the method has a broad substrate scope and good functional-group tolerance. Spectroscopic investigations and control experiments suggest the formation of a charge-transfer complex as the key step to activate the substrates.
Multiple Electrophilic C-H Borylation of Arenes Using Boron Triiodide
Oda, Susumu,Ueura, Kenta,Kawakami, Bungo,Hatakeyama, Takuji
supporting information, p. 700 - 704 (2020/02/04)
Electrophilic C-H borylation of arenes using boron triiodide has been developed. This reaction proceeded smoothly in the absence of additives, and the diiodoboryl group was installed at the most sterically accessible carbon, where the HOMO is localized to a certain extent. Moreover, regioselective multiple borylation of polycyclic aromatic compounds was achieved by using excess boron triiodide. The borylated intermediates were transformed into a variety of arylboron compounds such as arylboronates, boronic acids, and trifluoroborates.
BORON DIIODIDE COMPOUND, AND BORONIC ACID, BORONIC ESTER AND THE LIKE OBTAINED THEREFROM, AND PRODUCTION METHOD OF THEM
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Paragraph 0214; 0215, (2019/05/10)
PROBLEM TO BE SOLVED: To provide a method which enables simple production of a boronic acid, a boronic ester compound or the like suitable for production of various compounds. SOLUTION: The problem is solved by a boron diiodide compound represented by the following general formula (Y). (In the formula (Y), Ar is an n-valent heteroaryl ring, aryl ring having 10 or more carbon atoms, or substituted benzene ring, where at least one hydrogen atom in these rings may be substituted; n is an integer from 1 to 6; and at least one hydrogen atom in the compound represented by the formula (Y) may be substituted with deuterium.) COPYRIGHT: (C)2019,JPO&INPIT
Iron-catalysed enantioselective Suzuki-Miyaura coupling of racemic alkyl bromides
Iwamoto, Takahiro,Okuzono, Chiemi,Adak, Laksmikanta,Jin, Masayoshi,Nakamura, Masaharu
supporting information, p. 1128 - 1131 (2019/01/28)
The first iron-catalysed enantioselective Suzuki-Miyaura coupling reaction has been developed. In the presence of catalytic amounts of FeCl2 and (R,R)-QuinoxP?, lithium arylborates are cross-coupled with tert-butyl α-bromopropionate in an enantioconvergent manner, enabling facile access to various optically active α-arylpropionic acids including several nonsteroidal anti-inflammatory drugs (NSAIDs) of commercial importance. (R,R)-QuinoxP? is specifically able to induce chirality when compared to analogous P-chiral ligands that give racemic products, highlighting the critical importance of transmetalation in the present asymmetric cross-coupling system.
Efficient Rh-catalyzed C-H borylation of arene derivatives under photochemical conditions
Bheeter, Charles Beromeo,Chowdhury, Abhishek Dutta,Adam, Rosa,Jackstell, Ralf,Beller, Matthias
supporting information, p. 10336 - 10340 (2015/10/28)
Photocatalysis allows innovations in organic synthesis. Among the various catalytic reactions, CH-functionalizations offer valuable possibilities for the refinement of easily available building blocks. In this respect, catalytic borylation is of interest, too. So far, most of the catalytic borylation reactions are performed under thermal conditions at comparably high temperatures. Here, we describe a new synthetic route for efficient borylation reactions of arenes using a photocatalytic pathway. This novel approach allows the synthesis of a broad variety of borylated arenes and heteroarenes under mild conditions. Applying trans-[Rh(PMe3)2(CO)Cl] as an active photocatalyst and HBPin as an boron source, we achieved high TON. A catalytic cycle that relies on a Rh(i)-Rh(iii) interconversion is proposed.
