Bis(trifluoromethyl)sulfimide, bis(trifluoromethyl)-N-alkylsulfimides, and bis(trifluoromethyl)-N-alklysulfoxyimides

Abstract

Bis(trifluoromethyl)sulfimide, (CF&S=NH, results when ammonia and bis(trifluoromethy1)sulfur difluoride, (CF3)2SF2, are allowed to react in the presence of benzylamine. With primary amines, the corresponding bis(trifluoromethy1)-Nalkylsulfimides, (CF&S=NR (R = CH3, C2H5, i-C3H7), are formed. At reduced temperature, the sulfimide and N-alkylsulfimides are oxidized with m-chloroperbenzoic acid to the corresponding sulfoxyimide, (CF&S(O)=NH, and N-alkylsulfoxyimides, (CF&S(O)=NR.The chemical behavior of bis(trifluoromethy1)sulfur difluoride, (CF3)2SFz,l differs markedly from that of its more highly fluorinated analogues CF3SF3 and SF4. A qualitative comparison of the hydrolytic stability of these compounds shows that the ease of hydrolysis decreases in the order S F 4 > CF3SF3 > (CF3)2SF2. While S F 4 fumes in moist air2,3 and CF3SF3 hydrolyzes in water readily at 25 0C,4,5 (CF3)2SF2 can be stored in the presence of a large excess of water at 25 OC for at least 1 week with no apparent hydrolysis occurring. A similar difference in reactivity occurs with anhydrous ammonia where with S F 4 reaction proceeds even at -95 O C 3 whereas with (CF3)2SF2 no reaction takes place even upon heating. ' We now report that (CF3)2SF2 will undergo metathesis reactions with primary amines to produce a series of new bis(trifluoromethy1)-N-alkylsulfimides, (CF3)2S=NR. These moderately stable compounds are oxidized readily by using m-chloroperbenzoic acid (MCPBA) to form the bis(tri-fluoromethy1)-N-alkylsulfoxyimides, CF3S(0)=NR. 6 Also, we find that, in the presence of a primary amine, the reaction of ammonia and bis(trifluoromethy1)sulfur difluoride does occur readily to form the stable bis(trifluoromethy1)sulfimide, (CF~)ZS=NH.~ Oxidation of the latter with MCPBA at low temperature gives bis(trifluoromethy1)sulfoxyimide which was reported previously.6 discoloration occurs and lower yields result. Based on the ease with which the above reactions occur, the fact that ammonia does not react is somewhat unexpected. However, when a primary amine is added to the NH3-(CF3)2SF2 mixture, reaction does occur to produpe bis(trifluoromethyl)sulfimide, (CF3)2S=NH, in reasonable yield Other primary amines can be used in this reaction, also. When methylamine is used, the (CF3)2S=NH is formed in only trace quantities. Better yields are obtained when isopropylamine is utilized, but the product, bis(trifluor0methyl)-N-isopropylsulfimide, from the competing reaction is separated from (CF&S=NH with considerable difficulty. Because of its low volatility, (CF&S=NCH2C&, which is certainly formed, has not been isolated.The new bis(trifluoromethy1)sulfimide is more stable than its hydrocarbon analogue (CH3)2S=NH which was reported to be stable at -30 O C and to decompose slowly at 0 OCe8 The inherent instability of F2S-NH with respect to NSF and HF probably precludes its isolation as a stable species at 25 OC, although many of its derivatives are known and are table.^ Bis(trifluoromethy1)sulfimide is stable at 25 "C for extended Deriods in Pvrex glass bu...

Vibrational Spectra and Gas-Phase Structure of N-Methyl-S,S-bis(trifluoromethyl)sulfimide, CH3NS(CF3)2

“…CH 3 NdS(CF 3 ) 2 was synthesized by the reaction between (CF 3 ) 2 -SF 2 and CH 3 NH 2 . 11 The product was purified at reduced pressure by several trap-to-trap distillations. CH 3 NdS(CF 3 ) 2 reacted with moisture and had to be handled in a vacuum line and dry bag.…”

“…The first synthesis of this compound by the reaction of bis(trifluoromethyl)sulfur difluoride with methylamine was reported by Morse and Shreeve. 11 Preliminary vibrational spectra and NMR data did not provide any indication about the conformation of this imidosulfurous compound. The syn configuration was assumed in analogy with the structure of ClNd SF 2 , whose structure was known at that time.…”

Stable fluorinated sulfuranes and sulfurane oxides. Synthesis and reactions

“…Preparation of (CF3)2S=NCH3. 31 In the usual procedure, 1.0 mmol of (CF3)2S(OCF3)2 was condensed onto 3.0 mmol of CH3NH2 at -196 °C and reacted as with NH3. Bis(trifluoromethyl)-A'-methylsulfimide (0.82 mmol) and carbonyl fluoride (1.90 mmol) were recovered by trap-to-trap distillation.…”

Umsetzungen von Thiazylhalogeniden XSN (X = F, Cl) mit perfluorierten Iminen Rf2NH (Rf = F, CF3, CF3S, (CF3)2C, (CF3)2 S): Versuche zur Darstellung von Aminothiazylen (NSN)

“…Ein weiterer Hinweis fur das Auftreten einer =N-S=N Gruppe ist auch bei der Darstellung von R,N=S=NR, (R, = C,F,S [5], CF,S [6], CF,SS [2], CF,Se [?I) aus (R,),NH und ClSN sowie bei der Synthese von 3,3,5,5-Tetrakis (trifluormethyl) -3H-U4-2,4: 6- 1 [16, 171, 2 [13], 3s. [20], 3b [Zl], 5 [22], 7a [as], 7b [23], 8 [16], 11 [as], 12a [24], 120 [%I, FSN [15], HNF, [27] wurden gema13 den Literaturangaben dargestellt. Reektion yon 3b rnit FSN.…”