Electronic structure and basicity of trifluoro-N-methyl-N-(2-phenylethenyl)methanesulfonamide

The Wonderful Chemistry of Trifluoromethyl α‐Haloalkenyl Ketones

“…Their approximately equal intensities indicate the s-cis conformation. [5] Evidently, fluorinated -diethylamino-or -alkoxy-α-bromoenones 1j and 1k are typical push-pull systems each containing a very polar double bond and a highly electrophilic -carbon atom. [6,7] The chemistry of fluorinated enones of this type is usually quite trivial (nucleophilic addition/ -leaving group elimination sequence) and is not discussed in this review.…”

The structure and proton affinity of N‐benzyl‐N‐(allenyl)trifluoromethanesulfonamide: FT‐IR, DFT and ab initio study, NBO analysis

“…Upon addition of triflic or trifluoroacetic acid to liquid compound 1 , the intensity of the ν(CH = C = CH) band drops down and a band at 1662 cm −1 appears, which may be due to the stretching vibrations of the C = C or C = N bonds formed after protonation of the allenyl group in 1 . This is a distinctive feature, which clearly demonstrates the difference of molecule 1 from its N‐vinyl analogue, N‐methyl‐N‐(2‐phenylethenyl)triflamide CF 3 SO 2 N(Me)CH = CHPh ( 10 ), which is protonated only by triflic acid, and proves that the vinyl and allenyl carbon atoms in these molecules have different proton acceptor ability.…”

“…In the recently synthesized N‐styryltriflamide, the nitrogen atom LP is delocalized to both the C = C double bond and the triflyl group . As a result, the basicity of the β‐carbon atom of the double bond substantially decreases; the basicity of the nitrogen atom, although being lower than in the corresponding enamine, is still higher than in N‐methyltriflamide.…”

Regioselectivity Issues in the Addition of Grignard Reagents to Trifluoromethylated α‐Bromoenones

“…In fact, trifluoromethylated α-bromoenones 1 differ from their non-fluorinated analogs α-haloenones and enals as they have a sufficiently large positive charge on the olefinic -carbon and a higher carbon-carbon double bond polarization. [26,27] As a result, among α, -unsaturated carbonyl compounds, trifluoromethylated α-bromoenones are the most reactive Michael acceptors.…”