3,3,3-Trihalogeno-1-nitropropenes C(Hal)CH═CH(NO) (Hal = F, Cl, Br) in reaction with arenes in the superacid CFSOH (TfOH) at room temperature in 1 h afford 3,3,3-trihalogeno-1,2-diarylpropan-1-one oximes C(Hal)CH(Ar)-C(Ar)═NOH (CHal-oximes) in yields of 23-99%. Such CHal-oximes having one ortho-substituent in the aryl ring exist as atropoisomers in solutions at room temperature. Several cationic intermediates of this reaction were studied by means of NMR and DFT calculations, which proves the detailed reaction mechanism of the formation of CHal-oximes in TfOH. CHal-oximes (for Hal = Cl, Br) with DBU in DMF at microwave or thermal activation are cyclized into 5-halogeno-3,4-diarylisoxazoles in yields of 37-59%. CHal-oximes under the conditions of Beckmann rearrangement with PCl in benzene at room temperature in 24 h are turned at first into imidoyl chlorides (yields of 94-96%), which undergo transformation into the corresponding benzamides PhCONHCHPh(CHal) on silica gel (yields of 46-47%).

The formation of the corresponding benzyl cations [ArHC(+)-CH(X)CF3] takes place under protonation of E-/Z-2-halogeno-2-CF3 styrenes [ArCH═C(X)CF3, X = F, Cl, Br] in superacids. The structures of these new electrophiles were studied by means of NMR and theoretical DFT calculations. According to these data, in the case of bromo derivatives, the formed cations, most probably, exist as cyclic bromonium ions; however, in the cases of chloro and fluoro derivatives, open forms are more preferable. Subsequent reaction of these benzyl cations with arenes proceeds as Friedel-Crafts alkylation to afford 1,1-diaryl-2-halo-3,3,3-trifluoropropanes [Ar(Ar')CH-CH(X)CF3] in high yields (up to 96%) as a mixture of two diastereomers. The prepared halogenopropanes were easily converted into the corresponding mixtures of E-/Z-trifluoromethylated diarylethenes [Ar(Ar')C═CCF3] (in yields up to 96%) by dehydrohalogenation with base (KOH or t-BuOK). The mechanism of elimination (E2 and Ecb) depends on the nature of the leaving group and reaction conditions.

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A novel series of cyclometalated platinum(II) complexes bearing acyclic diaminocarbene (ADC) ancillary ligands was designed and prepared. Their photophysical properties were systematically studied through experimental and theoretical investigations. All complexes...