<i>gem-</i>Difluoroolefination of Diazo Compounds with TMSCF<sub>3</sub> or TMSCF<sub>2</sub>Br: Transition-Metal-Free Cross-Coupling of Two Carbene Precursors
作者:Mingyou Hu、Chuanfa Ni、Lingchun Li、Yongxin Han、Jinbo Hu
DOI:10.1021/jacs.5b09888
日期:2015.11.18
fragment resulting from a diazocompound and a difluorocarbene fragment derived from Ruppert-Prakash reagent (TMSCF3) or TMSCF2Br, has been developed. This gem-difluoroolefination proceeds through the direct nucleophilic addition of diazocompounds to difluorocarbene followed by elimination of N2. Compared to previously reported Cu-catalyzed gem-difluoroolefination of diazocompounds with TMSCF3, which possesses
Direct α-Monofluoroalkenylation of Heteroatomic Alkanes via a Combination of Photoredox Catalysis and Hydrogen-Atom-Transfer Catalysis
作者:Hao Tian、Qing Xia、Qiang Wang、Jianyang Dong、Yuxiu Liu、Qingmin Wang
DOI:10.1021/acs.orglett.9b01491
日期:2019.6.21
In this study, a new C(sp3)–H monofluoroalkenylation reaction involving cooperative visible-light photoredoxcatalysis and hydrogen-atom-transfer catalysis to afford products generated by selective hydrogen abstraction and radical–radical cross-coupling was described. This mild, efficient reaction shows high regioselectivity for the α-carbon atoms of amines, ethers, and thioethers and thus allows the
A novel method for the synthesis of 2,2-diaryl-1,1-difluoroethenes
作者:Ji Hoon Choi、In Howa Jeong
DOI:10.1016/j.tetlet.2007.12.028
日期:2008.2
β,β-Difluoro-α-phenylvinylstannane 3 was prepared in 60% yield from the reaction of β,β-difluoro-α-phenylvinylsulfone 2 with tributyltin hydride in refluxing benzene for 5 h. The cross-coupling reaction of 3 with aryl iodides bearing substituents such as proton, fluoro, chloro, bromo, methoxy, methyl, trifluoromethyl, and nitro on ortho, meta, para positions of the benzene ring in the presence of 10 mol %
Synthesis of α-CF<sub>3</sub> and α-CF<sub>2</sub>H amines <i>via</i> the aminofluorination of fluorinated alkenes
作者:Ling Yang、Wen-Xin Fan、E. Lin、Dong-Hang Tan、Qingjiang Li、Honggen Wang
DOI:10.1039/c8cc03364a
日期:——
A novel synthesis of α-CF3 and α-CF2H amines via the aminofluorination of gem-difluoroalkenes and mono-fluoroalkenes, respectively, is reported. The method employsSelectfluor as an electrophilic fluorine source and acetonitrile as a nitrogen source. Mechanistic studies revealed a single-electron oxidation/fluorine-abstraction/Ritter-type amination pathway. The protocol allowed the synthesis of a broad
Trifluoromethylation and Monofluoroalkenylation of Alkenes through Radical–Radical Cross‐Coupling
作者:Qiang Wang、Yi Qu、Hao Tian、Yuxiu Liu、Hongjian Song、Qingmin Wang
DOI:10.1002/chem.201901349
日期:——
The first visible‐light‐induced trifluoromethylation and monofluoroalkenylation of simple alkenes via a challenging radical–radicalcross‐coupling step was achieved. This method provided a mild, step‐economical and redox‐neutral route to privileged two different fluorinated difunctionalized allyl compounds. The utility of this method is illustrated by late‐stage modification of medically important