- Selective fluorination of substituted trichloromethyl benzenes by HF in liquid phase: Preparation of fluorinated building blocks
-
The selective fluorination by successive Cl/F exchanges of α,α,α-trichlorotoluene, substituted or not by a chlorine atom, was studied in the presence of HF as the fluorinating agent. The influence of the presence of a catalyst or a basic solvent (such as dioxane, pyridine, tributylphosphate) in order to control the fluorination was also investigated. In mild conditions (50 °C and after 1 h of reaction), HF in excess was required in order to obtained the trifluoromethylation by Cl/F exchanges. The presence of SbCl5 in small amount activated the Cl/F exchanges and only a stoichiometric amount of HF was required whatever the chlorinated molecules. Selective mono and difluorination could be obtained by using basic solvents.
- Piou, Alexandre,Celerier, Stephane,Brunet, Sylvette
-
experimental part
p. 1241 - 1246
(2011/01/12)
-
- A Novel Method for Converting Aromatic Acids into Trifluoromethyl Derivatives using BrF3
-
Aryltrifluoromethyl derivatives are obtained in good yields from the corresponding aryl carboxylic acids by reacting their dithionic esters with BrF3 under very mild conditions.
- Rozen, Shlomo,Mishani, Eyal
-
p. 2081 - 2082
(2007/10/02)
-
- Convenient Preparation of (Chlorodifluoromethyl)arenes. Useful Precursors for Aryldifluoromethyl Radicals
-
Chlorodifluoromethyl group was introduced into aromatic rings using bis(chlorodifluoroacetyl) peroxide which was readily prepared from corresponding acid anhydride with 30percent hydrogen peroxide, and the chlorine was successively replaced by hydrogen or
- Yoshida, Masato,Morinaga, Yoshihiro,Ueda, Masaaki,Kamigata, Nobumasa,Iyoda, Masahiko
-
p. 227 - 230
(2007/10/02)
-
