The possibility of deoxofluorination of β-keto esters using SF4 was investigated. The scope and limitation of the reaction were determined. The efficient method for the synthesis of β,β-difluorocarboxylic acids was elaborated based on the reaction. The set of mentioned acids, being the perspective building blocks for medicinal chemistry, were synthesized on multigram scale. The safety of SF4 use was discussed. The described method does not improve upon the safety of using SF4, but practical recommendations for working with the reagent are proposed. Despite the hazards of using toxic SF4, a significant increase of efficacy in the synthesis of medicinal-chemistry-relevant building blocks, based on the reaction, in comparison with earlier described approaches is shown.

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New CCl3‐ and CF3‐substituted enones, bearing additional hidden hydroxymethyl functions, were prepared by acylation of 4‐methylene 1,3‐dioxolanes. The synthesized enones are interesting building blocks for agrochemical and medicinal chemistry research. The reactivity of synthesized enones with various amines was studied, and enaminones 13 and 14 were obtained under NH3 interaction; the reaction with aliphatic primary amines afforded enaminones 17 in high yields as equilibrium mixtures of E and Z isomers. The reaction of fluorinated enone 9c with anilines afforded a mixture of products, including non‐aromatic heterocyclic compounds 25 and 26 bearing the CF3 group as well as furan 27 with CF3 and amino functions at positions 5 and 3, respectively. The hydrolysis of enone 9c afforded cyclic compound 11.

Diverse trifluoromethyl-substituted compounds were synthesized by deoxofluorination of cinnamic and (hetero)­aromatic carboxylic acids with sulfur tetrafluoride. The obtained products were used as starting materials in the preparation of novel fluorinated amino acids, anilines, and aliphatic amines - valuable building blocks for medicinal chemistry and agrochemistry.