Magic methyl alkylation

SCHEME 2 Basic cyclization followed by magic methyl alkylation. 

Another alkylative hydrolysis uses magic methyl . Thus, action of the 1,3-dithiolane (222) with methyl fluorosulfonate followed by treatment with sodium hydroxide leads to the formation of benzophenone (72S561). 

Krief et al. have shown that selenium ylides behave as their sulfur analogues and convert a variety of carbonyl compounds to oxiranes <89H(28)1203>. The latter compounds can be directly obtained by using R2Se=CHR /i-hydroxyalkylselenides (available from carbonyl compounds by addition of RSeCH2Li) may serve as suitable precursors as well, either in a two-step protocol, via the selenonium salt by alkylation with magic methyl (MeS03F), or directly by treatment with thallous ethoxide in chloroform. Oxidation of the /t-hydroxyalkylselenides with peracid, followed by treatment of the resulting selenone with base, results in oxirane formation (Scheme 60). 

The protolytic oxidative condensation of methane in Magic Acid solution at 60 °C is evidenced by the formation of higher alkyl cations such as t-butyl and t-hexyl cations (equation 42). It is not necessary to assume a complete cleavage of [CH5] to a free, energetically unfavorable methyl cation. The carbon-carbon bond formation can indeed be visualized through reaction of the C—H bond of methane with the developing methyl cation. 

Carbocation Generation from Alkyl Halides. Alkyl chlorides, fluorides, and bromides are convenient and frequently used precursors for generation of alkyl cations in HSOsF-SbFs systems.It should be noted, however, that the HSOsF-SbFs system is less suitable than SbFs for the generation of alkyl, especially secondary alkyl, cations from the corresponding alkyl halides. Ionization of cyclohexyl chloride In Magic Acid Is accompanied by Isomerization, 3deldlng the 1-methyl- 1-cyclopentyl cation (eq 3). ... 

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