Fluorinated sulfonamides

Figure 7.14 Inhibition of the steroid sulfatase by fluorinated sulfonamides. " ...

Synthesis of Fluorinated Sulfonamides. All compounds presented in this paper were prepared and provided by 3M Company. The general class of compound has been knewn for many years as surfactants (26,27). The general synthetic scheme is as follows ... 

Over 250 compounds of the general formula, RfSC A, were tested for toxicity against fire ants, where Rf is a fluoroaliphatic radical and A is any compatible chemical structure. Hie majority of the compounds were fluorinated sulfonamides, RfS02NR3R2, where R3 and... 

The fluoraza reagents consist of two types of compounds one in which a fluorine atom is bound to the nitrogen atom of an amide or, more often, a sulfonamide and one in which a fluorine atom is bound to the nitrogen atom of a tertiary amine such as pyridine, quinuclidine, or triethylenediamine 1,4-diaza-bicyclo[2 2.2]octane. The positive charge on the nitrogen is counterbalanced by a non-nucleophilic anion such as triflate or tetrafluoroborate. 

Amino groups bound to sulfur can be replaced by fluorine via diazotization. In contrast to carboxylic acid amides, fluorodediazoniation of aromatic sulfonamides IS readily accomplished to give sulfonyl fluorides in high yields [52, 7S (equation 16) Tetrazotization-fluorination of sulfanilamide can also be effected to give a 38% yield of p-fluorobenzenesulfonyl fluoride [52],... 

Treatment with sodium hypochlorite or hypobromite converts primary amines into N-halo- or N,N-dihaloamines. Secondary amines can be converted to N-halo secondary amines. Similar reactions can be carried out on unsubstituted and N-substituted amides and on sulfonamides. With unsubstituted amides the N-halo-gen product is seldom isolated but usually rearranges (see 18-13) however, N-halo-N-alkyl amides and N-halo imides are quite stable. The important reagent NBS is made in this manner. N-Halogenation has also been accomplished with other reagents, (e.g., sodium bromite NaBr02) benzyltrimethylammonium tribromide (PhCH2NMe3 Br3"), and NCS. The mechanisms of these reactions involve attack by a positive halogen and are probably similar to those of 12-47 and 12-49.N-Fluorination can be accomplished by direct treatment of amines °° or... 

Ford, L. A., DesMarteau, D. D. and Smith, D. W., Jr. 2005. Perfluorocyclobutyl (PFCB) aromatic polyethers Synthesis and characterization of new sulfonamide containing monomers and fluoropolymers. Journal of Fluorine Chemistry 126 653-660. 

Although a very powerful reagent for electrophiUc fluorinations, the J -fluoro compounds [83] (fluoro-pyridones, fluoro-J -sulfonamides) have not been widely used in fluorine-18 chemistry probably because they are prepared from F-fluorine. 

Fluorination of sulfonamides 147 and 148 takes place upon deprotonation with NaH and reaction with perchloryl fluoride, FCIO3, to give products 149 and 150 (Scheme 19) <2000JOC7583, 2000CPB1954>. The resulting A-fluorosultams 149 and 150 have been used for the asymmetric fluorination of aryl ketone enolates (vide infra). 

Asymmetric fluorination of the lithium enolate derived from tetralone 307 has been achieved with several new chiral A-fluoro-l,2-benzothiazine reagents (Scheme 44) <2000JOC7583, 2000CPB1954, see also 1999JFC(97)65>. For instance, sulfonamides 149 and 150 afford the opposite enantiomers of fluoroketone 308 in up to 79% yield and 62-70% ee. 

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