Reactions of fluorinated silanes with 2-nitrocinnamates

The interaction of 2-nitrocinnamates with silicon reagents Me3SiRf (Rf = CF3, C2F5, and C6F5) promoted either by sodium acetate in DMF or by tetrabutylammonium acetate in dichloromethane has been described. The reactions proceed as conjugate addition of fluorinated carbanion at the CC bond and afford 3-aryl-2-nitrobutanoates bearing a fluorinated substituent in good yields as diastereomeric mixtures in ratio from 1:1 to 1.6:1.

Nucleophilic addition of fluorinated carbanions to 2-nitrocinnamates using silicon reagents Me3SiRf (Rf = CF3, C2F5, and C6F5) is described.Figure optionsDownload as PowerPoint slideHighlights
► Conjugate addition of fluorinated carbanion to 2-nitrocinnamates.
► Nucleophilic trifluoromethylation using the Ruppert–Prakash reagent.
► Fluorinated silanes are activated by acetate anion.