Herein, the first decarboxylative hydroxylation reaction to synthesize phenols from benzoic acids is reported. The method overcomes the challenges associated with conventional decarboxylation of benzoic acids and can be applied even for the late-stage functionalization.
Synthesis of 4-trifluoromethyl-2<i>H</i>-chromenes <i>via</i> the reaction of 2-(trifluoroacetyl)phenols with vinyltriphenylphosphonium chloride
作者:Alexander S. Golubev、Petr N. Ostapchuk、Tatiana V. Strelkova、Nikolai D. Kagramanov、Kyrill Yu. Suponitsky、Rina U. Takazova、Nikolai D. Chkanikov
DOI:10.1039/d2ob01177h
日期:——
Substituted on the benzene ring 4-CF3-2H-chromenes have been prepared from substituted 2-(trifluoroacetyl)phenols and vinyltriphenylphosphonium chloride according to the Schweizer protocol in moderate to excellent yields. The influence of the type and the position of aromatic ring substituents on yields of 4-CF3-2H-chromenes have been investigated. It has been shown that 4-CF3-2H-chromenes are convenient
根据 Schweizer 协议,在苯环上取代的 4-CF 3 -2 H -色烯由取代的 2-(三氟乙酰基)苯酚和乙烯基三苯基氯化鏻以中等至优异的产率制备。研究了芳环取代基的类型和位置对4-CF 3 -2 H-色烯收率的影响。已经表明4-CF 3 -2 H-色烯是4-CF 3 -香豆素的方便前体。
α-Fluorinated aryl esters pose a challenge in synthesis via O-arylation of α-fluorinated carboxylates owing to their low reactivities. This limitation has been addressed by combining a silver catalyst with aryl(trimethoxyphenyl)iodonium tosylates to access α-fluorinated aryl esters. We envision that the catalytic system involves high-valent aryl silver species generated via the oxidation of silver(I)
Flash thermolysis of aryl trifluoroacetates: A new approach to trifluoromethylated aromatic compounds
作者:Y. Kobayashi、A. Nakazato、I. Kumadaki、R. Filler
DOI:10.1016/s0022-1139(00)81954-5
日期:1986.9
On the Mechanism of Ester Hydrolysis: Trifluoroacetate Derivatives
作者:Mariana A. Fernandez、Rita H. de Rossi
DOI:10.1021/jo990550j
日期:1999.8.1
The hydrolysis rate of trifluoacetates of ArX (X = p-CH3, H, p-F, p-Cl, and m-Cl) was measured as function of pH and buffer concentration. All the reactions were catalyzed by the buffer bases, and the Bronsted plot showed a small upward curvature. The kinetic isotope effect is ca. 2.5-2.3 for the reactions of water. The Hammett plots as well as the plots of log Kg VS PKlg are linear. The slopes of these plots are remarkably similar to those corresponding to the hydrolysis of aryl acetates and aryl formates. From these results, we conclude that the reaction corresponds to general base-catalyzed addition of water and break of the leaving group with no intermediate with finite lifetime despite the fact that the trifluoromethyl group stabilized the intermediate considerably.