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[reaction: see text]. The trifluoromethide ion generated in situ from TMSCF(3) and TBAT (tetrabutylammonium triphenyldifluorosilicate), as well as TMAF (tetramethylammonium fluoride), adds to the alpha,beta-unsaturated N-tert-butanesulfinimines exclusively in a 1,2 fashion with high diastereoselectivities, affording the first examples of chiral trifluoromethylated allylic amines.

A short stereocontrolled preparation of anti-alpha-(trifluoromethyl)-beta-amino alcohols is described, involving an initial CF(3) transfer to cinnamaldehyde and a one-step, three-component condensation of 3,3,3-trifluorolactic aldehyde, an alkenyl (aryl) boronic acid, and an amine. Applying this methodology to chiral 3,3,3-trifluorolactic aldehyde allowed us to generate an amino alcohol enantioselectively in 92% ee.

Energies, electronic structures, and thermodynamics of protonated and methylated dimethyl sulfoxide (DMSO) cations and dications were calculated using the density functional theory (DFT) method. The O-protonated structure 2 was found to be 37.0 kcal/mol more stable than the S-protonated 3. For diprotonated DMSO dication, the O, O-diprotonated form 6 was found to be the global minimum, more stable by 20.8 kcal/mol than O,S-diprotonated 7. Interestingly, for dimethylated DMSO dication, O,O-dimethylated 11 and O,S-dimethylated 12 are isoenergetic. (13)C, (17)O, and (33)S NMR chemical shifts of the cations and dications were calculated using the GIAO-MP2 method and compared with the available experimental data.