Synthesis and properties of trifluoromethylthiirane

Reaction of N,N‐Disubstituted Polyfluoroalkanethioamides with Diazomethane: Entry to New Thiirane Derivatives

“…The crude products were characterized by NMR ( 1 H, 13 C, 19 F) spectroscopy and GC-MS, and the obtained data are in good agreement with the structures 2a-e. In the 13 It is worth mentioning that the syntheses of 1-fluoroalkyl enamines containing dialkylamino group were performed previously using other methods. [25][26][27][28][29][30] They include the nucleophilic substitution of a vinylic fluorine in fluoroalkenes by lithium amides, [25] addition of diethylamine to perfluorobut-2yne, [26] Wittig reaction involving trifluoroacetamides, [27] C-trifluoromethylation of dialkylamides with the reagent combination P(NEt 2 ) 3 /CF 3 Br in the presence of BCl 3 , [28] nucleophilic substitution of a vinylic halogen in β-chloroand β-bromo-β-(trifluoromethyl)styrenes by secondary amines.…”

“…The composition of the isolated stereoisomers 8a and 8a′ is consistent with elemental analysis and FAB-MS data, which showed an intense peak of the deprotonated molecule [M -H]at m/z 393 in negative ionization mode for both compounds. The NMR ( 1 H, 13 C, 19 F) spectra of the two products are very similar with respect to chemical shifts and coupling constants. In the 19 F NMR spectra, the signals of trifluoromethyl groups of compounds 8a and 8a′ were found at -76.8 and -76.4 ppm, correspondingly.…”

“…© 2020 Wiley-VCH GmbH 3.97 ppm (J = 12.4 Hz) of the minor one. The marked difference in the 13 C NMR chemical shifts was observed for the equivalent C-3 and C-6 carbon atoms of the 1,4-dioxane ring in compounds 8a and 8a′, which appeared at 56.2 and 60.7 ppm, respectively.…”

“…[7] The known methods for the preparation of thiiranes containing polyfluoroalkyl substituents include thermolysis (vacuum pyrolysis) of 1,3-dithietane-1,1-dioxides [8][9][10][11] and cyclizations involving polyfluoroalkyl-substituted sulfenyl chlorides or disulfides. [12][13][14][15] One of the general methods for the synthesis of thiiranes, which is based on the reaction of thiocarbonyl compounds with diazo compounds (Scheme 1), is applicable for the preparation of fluorinated thiirane derivatives too. This method gives access to the functionalized thiiranes and allows to use different fluorinated thiocarbonyl compounds (hexafluorothioacetone, [16,17] methyl trifluorodithioacetate [18] ) as well as diazo compounds [bis(trifluoromethyl)diazomethane, [11,17] 1,1,1-trifluorodiazoethane, [19] methyl 2-diazo-3,3,3-trifluoropropanoate [20] ].…”