Reagents. In a typical run, to a stirred solution of sulfoxide 15 (251 mg, 1.0 mmol) in THF (10 mL) was added 1.58 M n-butyllithium (0.13 mL, 0.2 mmol) under N2 atmosphere at -78 °C.The mixture was stirred for 15 min at -78 °C. After hydrolysis and extraction with dichloromethane (3 X 20 mL), the extract was dried with anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue was purified by column chromatography (silica gel; eluent, hexane/EtOAc = 7/3) to give n-butyl p-tolyl sulfoxide (5a) in 13% and recovered sulfoxide 15 in 83% yield. Optical rotation (Md26) of the recovered sulfoxide 15 is 0°( c = 1.0, acetone).Reactions of 180-Labeled Phenyl p-Tolyl Sulfoxide (4c) with n -Butyllithium. The reaction was carried out according to the same procedure of the optically active sulfoxide 4b with n-butyllithium. The products were separated by column and preparative liquid chromatography, and their 180 contents were determined by mass spectrometry. The 180 content of each sulfoxide is 38 atom %.Cross-Over Reaction of18O-Labeled Diphenyl Sulfoxide (7b) and Unlabeled Di-p-tolyl Sulfoxide (8) with Phenyllithium. To a solution of sulfoxide 7b (101 mg, 0.5 mmol) and di-p-tolyl sulfoxide (8,115 mg, 0.5 mmol) in THF (10 mL) under N2 atmosphere at -78 °C was added 1.8 M phenyllithium (0.11 mL, 0.2 mmol) in ether/cyclohexane solution. After 15 min, water was added and the mixture was extracted with dichloromethane (3 X 20 mL). The extract was dried with anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure.The residue was purified by preparative liquid chromatography to afford diphenyl sulfoxide in 26%, phenyl p-tolyl sulfoxide in 51%, and di-p-tolyl sulfoxide in 17% yield. The 180 contents of three sulfoxides are 19 atom % by mass spectrometry.

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Potassium fluoride on alumina was proved to be an efficient dehydrohalogenating agent for the synthesis of per(poly)fluoroalkyl substituted alkenes and alkynes. The reaction was simple, mild and the yields ranged from good to excellent.

The electronic structures of 17 perchlorofiuoroolefins and perfluoroolefins were calculated using the MNDO method. Based on these calculations combined with the perturbation theory, a good structure‐reactivity relationship of perchlorofluoroolefins has been established. In the case of internal olefins, the direction of nucleophilic attack is governed not only by the perturbation energy of the ground state, but also by the stability of the anionic intermediate and the activation energy of the reaction.