67640-39-5Relevant academic research and scientific papers
Halex reactions of aromatic compounds catalysed by 2-azaallenium, carbophosphazenium, aminophosphonium and diphosphazenium salts: A comparative study
Pleschke, Axel,Marhold,Schneider,Kolomeitsev,R?schenthaler
, p. 1031 - 1038 (2007/10/03)
An increasing number of biologically active compounds in the pharma and agro-chemical sector contain carbon fluorine bonds. One of the most common methods to introduce fluorine into intermediates is the well-investigated halogen-exchange reaction, in which chloro- and bromoaromatics activated towards nucleophilic substitution, react with a fluoride source to yield the corresponding fluoroarenes. In general, the reaction is supported by phase-transfer catalysts. The use of a new class of very active phase-transfer catalysts gives the possibility of substituting even halogens with weak activation giving a convenient access to interesting compounds that are not available so far and opening up new synthetic routes in Halex chemistry. Our new classes of catalysts, CNC+ (1a), PNC+ (2a) and several different approaches presented by other groups are described and experimental results discussed.
Process for preparing nuclear-fluorinated aromatics
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, (2008/06/13)
The present invention relates to the preparation of nuclear-fluorinated aromatics by reacting, with a fluoride at 40 to 260° C., an aromatic compound substituted at the nucleus with halogen that is exchangeable for fluorine in the presence of at least one compound of the formula (I) where A, B, and Any have the meanings specified in the disclosure.
Process for the preparation of difluorobenzenes
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, (2008/06/13)
Difluorobenzene is prepared by a multistep process involving fluorination of dichlorobenzoyl chloride to provide difluorobenzoyl fluoride, conversion thereof to difluorobenzoyl chloride, hydrogenation of this to difluorobenzaldehyde and decarbonylation of the aldehyde to difluorobenzene.
