90850-47-8Relevant articles and documents
Octafluorotoluene as a Reagent for the Selective Protection of Alcoholic and Phenolic Functions: Synthesis and Cleavage of Perfluorotolyl and other Perfluoroaryl Ethers of Steroids and Other Model Compounds
Jarman, Michael,McCague, Raymond
, p. 1301 - 1341 (2007/10/02)
Heptafluorotolyl derivatives of phenol, of the steroids oestrone, oestradiol , cholesterol, testosterone, cortisol and 4-hydroxyandrostene-3,17-dione, of the phenyl-substituted alcohols 1- and 2-phenylethanol and 3-phenylpropanol and of catechol were prepared by phase-transfer catalysed reactions with octafluorotoluene.Reaction with sodium methoxide in dimethylformamide regenerated the alcohol or phenolic functions, by a stepwise process involving replacement of fluorine substituents by methoxyl followed by aryl-oxygen cleavage.Phenols were regenerated more rapidly than alcohols and could be deprotected selectively.The perfluorotolyl group was stable under reducing and oxidising conditions and was compatible with Grignard reagents.Pentafluoropyridine similarly, and more rapidly gave perfluoropyridyl derivatives of oestradiol , which could similarly be cleaved with sodium methoxide.Hexafluorobenzene was relatively unreactive under phase transfer conditions and its derivatives with oestrone was cleaved only with difficulty.Perfluoro-o-xylene reacted with catechol to give dibenzodioxin derivatives from which catechol was regenerated using sodium methoxide.
