Radical Reactions of Alkyl 2-Bromo-2,2-difluoroacetates with Vinyl Ethers: “Omitted” Examples and Application for the Synthesis of 3,3-Difluoro-GABA
作者： Ivan S. Kondratov , Maksym Ya. Bugera , Nataliya A. Tolmachova , Ganna G. Posternak , Constantin G. Daniliuc
关键词:
摘要: Addition reactions of perfluoroalkyl radicals to ordinary or polyfluorinated alkenes have been frequently used synthesize perfluoroalkylated organic compounds. Here ethyl/methyl 2-bromo-2,2-difluoroacetate, diethyl (bromodifluoromethyl)phosphonate, [(bromodifluoromethyl)sulfonyl]benzene, and ethyl 2-bromo-2-fluoroacetate were involved in Na2S2O4-mediated radical additions vinyl ethers the presence alcohols give difluoro monofluoroacetyl-substituted acetals corresponding difluoromethylphosphonate- (difluoromethylphenyl)sulfonyl-substituted alkyl acetals. This methodology has also applied as a key step synthesis hitherto unknown 3,3-difluoro-GABA, completing series isomeric GABAs. Comparison pKa values 3-fluoro- 3,3-difluoro-GABA with that fluorine free parent compound showed introduction each lead acidification both amino carboxyl functions by approximately one unit.
acs.org
sci-hub.se 参考文章(83)
S. S. Batsanov, Van der Waals Radii of Elements Inorganic Materials. ,vol. 37, pp. 871- 885 ,(2001) , 10.1023/A:1011625728803
Charles S. Thomoson, William R. Dolbier, Carbomethoxydifluoromethylation of enol acetates with methyl (chlorosulfonyl)difluoroacetate using visible-light photoredox catalysis. Synthesis of 2,2-difluoro-γ-ketoesters Journal of Fluorine Chemistry. ,vol. 178, pp. 327- 331 ,(2015) , 10.1016/J.JFLUCHEM.2015.07.018
Piotr Dudziński, Andrej V. Matsnev, Joseph S. Thrasher, Günter Haufe, Ambiphilic Properties of SF5CF2CF2Br Derived Perfluorinated Radical in Addition Reactions Across Carbon–Carbon Double Bonds Organic Letters. ,vol. 17, pp. 1078- 1081 ,(2015) , 10.1021/ACS.ORGLETT.5B00268
Iwao Ojima, Fluorine in medicinal chemistry and chemical biology Wiley. ,(2009) , 10.1002/9781444312096
Zbyszek Otwinowski, Wladek Minor, Processing of X-ray diffraction data collected in oscillation mode Methods in Enzymology. ,vol. 276, pp. 307- 326 ,(1997) , 10.1016/S0076-6879(97)76066-X
Marie-Charlotte Belhomme, Alexandre Bayle, Thomas Poisson, Xavier Pannecoucke, Copper‐Catalyzed Innate Ethoxycarbonyldifluoromethylation of Electron‐Rich Arenes European Journal of Organic Chemistry. ,vol. 2015, pp. 1719- 1726 ,(2015) , 10.1002/EJOC.201403656
R.B. Silverman, M.A. Levy, Substituted 4-aminobutanoic acids. Substrates for gamma-aminobutyric acid alpha-ketoglutaric acid aminotransferase. Journal of Biological Chemistry. ,vol. 256, pp. 11565- 11568 ,(1981) , 10.1016/S0021-9258(19)68438-3
Stig Valdersnes, Leiv K. Sydnes, Preparation of 2‐Ethoxy‐3‐hydroxy‐4‐(perfluoroalkyl)tetrahydropyran Derivatives from Substituted 4‐Ethoxybut‐3‐en‐1‐ols European Journal of Organic Chemistry. ,vol. 2009, pp. 5816- 5831 ,(2009) , 10.1002/EJOC.200900687
Chunghyeon Yu, Naeem Iqbal, Sehyun Park, Eun Jin Cho, Selective difluoroalkylation of alkenes by using visible light photoredox catalysis. Chemical Communications. ,vol. 50, pp. 12884- 12887 ,(2014) , 10.1039/C4CC05467A
Wadih Ghattas, Corinna R Hess, Gilles Iacazio, Renaud Hardré, Judith P Klinman, Marius Réglier, None, Pathway for the Stereocontrolled Z and E Production of α,α-Difluorine-Substituted Phenyl Butenoates Journal of Organic Chemistry. ,vol. 71, pp. 8618- 8621 ,(2006) , 10.1021/JO061022S