Azoles as Reactive Nucleophiles with Cyclic Perfluoroalkenes

Abstract

Di- and multiazole-substituted fluorocyclic products (2-13) were readily synthesized in good to high yields. These were synthesized by nucleophilic substitution reactions of perfluorocycloalkenes with azoles (i.e., imidazole, triazole) involving simple reaction procedures. Interestingly, these azoles were later found to be reactive not only with the vinylic, but also with the allylic fluorine atoms. This resulted in the substitution of up to six azoles on the fluorinated rings. Stoichiometry plays a key role in determining the degree of substitution. For comparison, the analogous reactions of N-substituted 1-(trimethylsilyl)-imidazole and 1-(trimethylsilyl)-1,2,4-triazole were also investigated. All of the new compounds were fully characterized by elemental, spectral ((19)F, (1)H, (13)C NMR), and thermal differential scanning calorimetry (DSC) analyses.

AB-type monomers for the preparation of perfluorocycloalkene (PFCA) aryl ether polymers

“…Previous reports of multiple nucleophilic substitutions (ranging 4-6) of PFCP provides additional evidence of fluoride-catalyzed rearrangement, which would not be possible with the mechanism shown in Fig. 4 [43].…”

Triarylamine-enchained semifluorinated perfluorocycloalkenyl (PFCA) aryl ether polymers

“…The literature suggests, in suitable conditions, multiple nucleophilic substitutions on PFCP ring are possible [39]. Model reactions also support the multiple substitutions on PFCP rings (Scheme 7).…”

Syntheses of Atypically Fluorinated Peptidyl Macrocycles through Sequential Vinylic Substitutions

“…However, relative to reagents 1 and 2 , we sought broader nucleophile participation and product geometries that are more compatible with smaller polyheterocyclic structures. Rather than aromatic substitutions, we choose to examine vinylic substitutions of fluoride from octafluorocyclopentene (OFCP, 3 ; Figure ) . Simple phenols, amines, mercaptans, and alcohols are known to displace fluoride from this commercial reagent, and the extent of substitution could be varied.…”

“…Rather than aromatic substitutions, we choose to examine vinylic substitutions of fluoride from octafluorocyclopentene (OFCP, 3 ; Figure ) . Simple phenols, amines, mercaptans, and alcohols are known to displace fluoride from this commercial reagent, and the extent of substitution could be varied. Herein, we report that successive, dissymmetric substitutions of fluoride on OFCP by functionalized peptides occurs readily, which provides a flexible means to generate constrained fluorinated macrocycles.…”