Fluoroalkene chemistry: Part 3. Reactions of arylthiols with perfluoroisobutene, perfluoropropene and chlorotrifluoroethene

Reactions of perfluoroisobutene (PFIB), perfluoropropene (PFP) and chlorotrifluoroethene (CTFE) with benzenethiol and 2-methoxybenzenethiol in acetonitrile, with potassium carbonate as base, were compared. PFIB reacted with benzenethiol to give ketene thioacetal (CF₃)₂CC(SAr)₂ and with 2-methoxybenzenethiol to give mono- and bis-vinyl species (CF₃)₂CCFSAr and (CF₃)₂CC(SAr)₂. PFP reacted with both thiols to give the addition product CF₃CFHCF₂SAr and vinyl isomers CF₃CFCFSAr (6:1 E/Z ratio). CTFE reacted with several methoxy-substituted arylthiols to give addition products of structure CFClHCF₂SAr. The arylthiols used throughout the study imitate biological thiols. Inhalation toxicities of the fluoroalkenes decrease in the order PFIB > PFP > CTFE and correlate with their reactivities towards the model thiols, supporting the current view that their toxicity relates to their ability to react with biological thiols.