Silver-promoted decarboxylative radical addition/annulation of oxamic acids with gem-difluoroolefins: concise access to CF2-containing 3,4-dihydroquinolin-2-ones
Carboboration‐Driven Generation of a Silylium Ion for Vinylic C−F Bond Functionalization by B(C
<sub>6</sub>
F
<sub>5</sub>
)
<sub>3</sub>
Catalysis
作者:Tetsuji Yata、Yoshihiro Nishimoto、Makoto Yasuda
DOI:10.1002/chem.202103852
日期:2022.2
B(C6F5)3-catalyzed reactions between fluoroalkenes and silyl ketene acetals gave vinylic C−F bond-functionalized products under mild and simple conditions. Carboboration reaction of fluoroalkenes generates an oxygen-stabilized silylium ion to facilitate the C−F bond cleavage. DFT and IBO studies were performed to clear the reaction mechanism. A comparative study of α-chloro or bromostyrenes demonstrated
Gold N‐Heterocyclic Carbene Catalysts for the Hydrofluorination of Alkynes Using Hydrofluoric Acid: Reaction Scope, Mechanistic Studies and the Tracking of Elusive Intermediates
作者:Raphaël Gauthier、Nikolaos V. Tzouras、Ziyun Zhang、Sandrine Bédard、Marina Saab、Laura Falivene、Kristof Van Hecke、Luigi Cavallo、Steven P. Nolan、Jean‐François Paquin
DOI:10.1002/chem.202103886
日期:2022.1.19
Unconventional fluorination: The development of the chemoselective gold-catalysed hydrofluorination of terminal alkynes using aqueous HF and an easily accessible N-heterocyclic carbene-gold pre-catalyst is reported. Following the observation and isolation of unprecedented organometallic intermediates and computational studies, a catalytic cycle is proposed, featuring an in situ generation of the chemoselective
Fluorine containing cyclopropanes: synthesis of aryl substituted all-<i>cis</i> 1,2,3-trifluorocyclopropanes, a facially polar motif
作者:Zeguo Fang、David B. Cordes、Alexandra M. Z. Slawin、David O'Hagan
DOI:10.1039/c9cc05749h
日期:——
described for the first time. The three fluorines located on each of the cyclopropyl carbons with a stereochemistry where they are all on the same face of the cyclopropane, imparts a significant polarity to the molecule, and the inherent conformational rigidity and lowering of log P makes this motif attractive for exploration as a substituent for pharmaceuticals and agrochemicals research.
Process for the preparation of .alpha.-flurostyrene
申请人:Hoechst Aktiengesellschaft
公开号:US05313001A1
公开(公告)日:1994-05-17
Process for the preparation of .alpha.-fluorostyrene from fluoroolefins: ##STR1## Z=hydrogen, fluorine, chlorine X=iodine, bromine, chlorine. A halogenated aromatic (I) is reacted with a fluorine-substituted ethylene (II) in the presence of a palladium catalyst to give an .alpha.-fluorostyrene (III), it being possible for R to be a hydrogen atom, a halogen atom, a C.sub.1 -C.sub.4 -alkyl group, a C.sub.1 -C.sub.5 -alkoxy group, an amino, alkylamino or dialkylamino group, an aryl radical or a fused aryl or heteroaryl ring, a hydroxyl or hydroxyalkyl group, a trifluoromethyl or perfluoroalkyl group or a nitro group.
Self‐Sustaining Fluorination of Active Methylene Compounds and High‐Yielding Fluorination of Highly Basic Aryl and Alkenyl Lithium Species with a Sterically Hindered
<i>N</i>
‐Fluorosulfonamide Reagent
作者:Yuhao Yang、Gerald B. Hammond、Teruo Umemoto
DOI:10.1002/anie.202211688
日期:2022.10.24
By developing a sterically hindered fluorinating agent, N-fluoro-N-(tert-butyl)-tert-butanesulfonamide (NFBB), we discovered a conceptually novel base-catalyzed, self-sustaining fluorination of active methylene compounds and achieved an unprecedented high-yield fluorination of highly basic (hetero)aryl and alkenyl lithium species.