A convenient synthesis of fluorinated vinyl ethers derived from di-O-isopropylidenehexofuranose and O-isopropylidenepentofuranose

Synthesis of Fluorinated Amides Starting from Carbohydrates Based on the Claisen Rearrangement

“…These compounds have been obtained in a reaction of a potassium alkoxide with one of the fluorinated olefins: (a) 1,1,3,3,3‐pentafluoroprop‐1‐ene (2H‐PFP) or (b) hexafluoroprop‐1‐ene (HFP). As expected according to the earlier results, [23–24,26] nucleophilic substitution occurred at the terminal CF 2 = position, rather than at the =C(X)CF 3 , because of the most stable carbanion transition state, in which the negative charge is set on a carbon atom attached to a highly stabilizing CF 3 group.…”

“…In our previous work, we have presented the synthesis of fluorovinyl ethers derived from di-O-isopropylidene-hexofuranose and O-isopropylidene-pentofuranose. [23] Unfortunately, as has been shown in those studies, the obtained compounds did not undergo Claisen rearrangement reaction. It was quite surprising since analogous fluorinated allyl vinyl ethers that are not carbohydrate derivatives have undergone such transformations effortlessly.…”

“…In our previous work, we have presented the synthesis of fluorovinyl ethers derived from di‐ O ‐isopropylidene‐hexofuranose and O ‐isopropylidene‐pentofuranose [23] . Unfortunately, as has been shown in those studies, the obtained compounds did not undergo Claisen rearrangement reaction.…”

gem‐Heteroatom‐Substituted Fluoroalkenes as Mimics of Amide Derivatives or Phosphates: A Comprehensive Review

“…In 2014, Marciniak and co-workers synthesized new carbohydrates bearing fluorinated vinyl ethers via an addition-elimination reaction of alkoxides on fluorinated alkenes. [19] Several polyfluoropropenes were used rendering low to moderate yields. The stereoselectivity depends on repulsive interaction between fluorine atoms and steric congestion of trifluoromethyl and ether moieties (Scheme 4).…”

“…[5] Furthermore, the NMR properties of fluorine nuclei allow the development of new diagnostic tools for several fields such as magnetic resonance imaging (MRI) and peptide/protein engineering. [6] Among the numerous fluorinated motifs, monofluoroalkenes emerged as particular relevant and versatile compounds that have found many applications such as bioactive compounds [7] or 19 F NMR labeling, [8] for example. Another relevant feature of the monofluoroalkene moiety is its recognition as a stable, isosteric and isoelectronic mimic (albeit with a lower dipolar moment value) of the amide bond (Scheme 1A) [9] .…”