N-Fluoro amines and their analogues as fluorinating reagents in organic synthesis

Abstract

The data on the synthesis and application in organic synthesis of fluorinating compounds containing N–F bonds are surveyed and systematised. The reagents are classified into two categories, viz., neutral (perfluoro-N-fluoropiperidine, N-fluoro-2-pyridone, N-fluorosulfonamides, N-fluoro-N-alkylamides, N-fluorobis(trifluoromethyl)sulfonylamine, N-fluorobenzo- 1,3,2-dithiazole 1,1,3,3-tetroxide, N-fluoro sultams) and ionic reagents (N-fluoropyridinium, N-fluoroquinuclidinium and 1- alkyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane salts). A comparative analysis of the fluorinating activity of the reagents depending on their structure and the nature of the solvent is carried out taking into account theoretical calculations. The possibility of fluorination of various classes of organic compounds is discussed. The mechanisms of fluorination with N–F compounds are analysed using kinetic data. The advantages and disadvantages of N- fluoro amines in comparison with elemental fluorine, xenon difluoride and other fluorinating reagents are considered. The influence of the nature of the solvent on the fluorinating activity of N-fluoro amines and their analogues is discussed. The bibliography includes 245 references.