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We developed enhanced method for low temperature and good yield preparation of aryl and heteryl sulfur pentafluorides from chlorotetrafluorides using mercury oxide - hydrogen fluoride and mercury oxide - pyridinium poly(hydrogen fluoride) media as the fluorinating reagents.

An approach to the synthesis of the novel cyclic sulfonimidoyl fluorides was elaborated based on the electrophilic fluorination of 1-oxo-2H-1,2,4-benzothiadizines with Selectfluor®. Crystal structure of 1-oxo-1-fluoro-3-phenyl-1,2,4-benzothiadiazine was determined.

Treatment of gem -dichlorocyclopropanecarboxylic acids with SF 4 yields many rearranged products, i.e. 1,1-difluoro-substituted olefins. The mechanism of the rearrangement is discussed.

The compounds C 6 H 5 XCF 3 and C 6 HXCH 3 (X=S, SO, SO 2 ) have been investigated by multinuclear 1 H, 13 C, 17 O, 19 F and 33 S NMR spectroscopy and quantum chemical methods (MNDO in the PM3 parametrization). Compounds with XCF 3 , SOCH 3 and SO 2 CH 3 groups have been characterized with effective non-planar conformations. A nearly planar effective conformation has been found for C 6 H 5 SCH 3 . As the two lone pairs (LP) of sulphur in the sulphides are essentially non-equivalent with their orbital energies differing considerably, only one LP (with a higher energy level) can participate in the p-π conjugation. In compounds with XCF 3 , SOCH 3 and SO 2 CH 3 groups, the electron-withdrawing π-inductive effect is the main factor determining the π-charge distribution in the benzene ring. The p-π conjugation is essentially distorted in C 6 H 5 SCF 3 due to its various conformations. Electron-donating p-π conjugation only contributes considerably to the π-charge distribution in the benzene ring in C 6 H 5 SCH 3 . An interpretation of the NMR spectra of the considered compounds is given on the basis of the quantum chemical calculations.

Alkyl perfluoroalkanedithiocarboxylates have been synthesized from 1,1-dichloroperfluoroalkyl propyl sulfides by reaction with zinc sulfide or cadmium sulfide.

1,1-Dichloropolyfluoropentylsulfenyl chlorides react with lithium hexamethyldisilylamide with the formation of N,N -bis(trimethylsilyl)- 1-chloro-polyfluoropentyl-1-en-sulfenamide.

Several recent developments in our laboratories have made it possible to elaborate a general method for preparing optically pure fluorine containing α-amino acids starting from a Ni(II)-complex ( 1 ) of a Schiff's base derived from (S)-o-[(benzylpropyl)amino]-benzophenone (BBP) and glycine or alanine. Alkylation of ( 1 ) with fluorine-substituted benzyl halides and aldehyde condensation result, respectively, in fluorine-containing S-Phe and its α-methyl derivatives, 2R,3S-, 2S,3R-, 2R,3R-PhSer and 2S,3S-β-perfluoroalkyl Ser in good chemical and optical yields. Simplicity of the synthetic procedure, ease of recovery of the chiral auxiliary (BBP), and the possibility of obtaining optically pure fluorine containing amino acids make this method attractive. The influence of fluorine atoms or fluorine containing groups and reaction conditions on the stereochemical results in the reactions of this type will be discussed.