126489-67-6Relevant academic research and scientific papers
Photocarboxylation of Benzylic C-H Bonds
Meng, Qing-Yuan,Schirmer, Tobias E.,Berger, Anna Lucia,Donabauer, Karsten,K?nig, Burkhard
, p. 11393 - 11397 (2019/08/20)
The carboxylation of sp3-hybridized C-H bonds with CO2 is a challenging transformation. Herein, we report a visible-light-mediated carboxylation of benzylic C-H bonds with CO2 into 2-arylpropionic acids under metal-free conditions. Photo-oxidized triisopropylsilanethiol was used as the hydrogen atom transfer catalyst to afford a benzylic radical that accepts an electron from the reduced form of 2,3,4,6-tetra(9H-carbazol-9-yl)-5-(1-phenylethyl)benzonitrile generated in situ. The resulting benzylic carbanion reacts with CO2 to generate the corresponding carboxylic acid after protonation. The reaction proceeded without the addition of any sacrificial electron donor, electron acceptor or stoichiometric additives. Moderate to good yields of the desired products were obtained in a broad substrate scope. Several drugs were successfully synthesized using the novel strategy.
Enantioselective Decarboxylative Cyanation Employing Cooperative Photoredox Catalysis and Copper Catalysis
Wang, Dinghai,Zhu, Na,Chen, Pinhong,Lin, Zhenyang,Liu, Guosheng
, p. 15632 - 15635 (2017/11/14)
The merger of photoredox catalysis with asymmetric copper catalysis have been realized to convert achiral carboxylic acids into enantiomerically enriched alkyl nitriles. Under mild reaction conditions, the reaction exhibits broad substrate scope, high yields and high enantioselectivities. Furthermore, the reaction can be scaled up to synthesize key chiral intermediates to bioactive compounds.
Beyond benzyl grignards: Facile generation of benzyl carbanions from styrenes
Grigg, R. David,Rigoli, Jared W.,Van Hoveln, Ryan,Neale, Samuel,Schomaker, Jennifer M.
, p. 9391 - 9396 (2012/08/29)
Benzylic functionalization is a convenient approach towards the conversion of readily available aromatic hydrocarbon feedstocks into more useful molecules. However, the formation of carbanionic benzyl species from benzyl halides or similar precursors is far from trivial. An alternative approach is the direct reaction of a styrene with a suitable coupling partner, but these reactions often involve the use of precious-metal transition-metal catalysts. Herein, we report the facile and convenient generation of reactive benzyl anionic species from styrenes. A CuI-catalyzed Markovnikov hydroboration of the styrenic double bond by using a bulky pinacol borane source is followed by treatment with KOtBu to facilitate a sterically induced cleavage of the C-B bond to produce a benzylic carbanion. Quenching this intermediate with a variety of electrophiles, including CO2, CS2, isocyanates, and isothiocyanates, promotes C-C bond formation at the benzylic carbon atom. The utility of this methodology was demonstrated in a three-step, two-pot synthesis of the nonsteroidal anti-inflammatory drug (±)-flurbiprofen. Make or break: The facile generation of benzyl anion equivalents from styrenes has been achieved by using a Cu-catalyzed hydroboration in conjunction with sterically induced cleavage of the C-B bond with tBuOK. Quenching this reactive intermediate with heteroallene electrophiles yields benzylic C-C bond formation (see scheme), and the utility of this methodology has been demonstrated by a synthesis of the nonsteroidal anti-inflammatory drug (±)-flurbiprofen. Copyright
BIPHENYLACETAMIDE DERIVATIVE
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, (2011/10/04)
The present invention provides a compound of formula (I) or a salt thereof, wherein R1, R2 and R3 are independently selected from the group consisting of hydrogen atom, fluorine atom, chlorine atom, bromine atom, C1-6 alkyl, C1-6 alkoxy substituted with fluorine atom, and others; R4 and R5 are independently selected from the group consisting of hydrogen atom, fluorine atom, chlorine atom, C1-6 alkyl, C1-6 alkoxy substituted with fluorine atom, and others; R6 and R7 are independently selected from the group consisting of hydrogen atom, fluorine atom, methyl, ethyl, hydroxy group, and others; and R8 and R9 are independently selected from the group consisting of hydrogen atom, C1-6 alkyl, and others, which is useful as an agent for treating or preventing various types of epilepsy including partial seizures and/or generalized seizures.
