Ab Initio Investigations of the Rearrangements of some β-Haloalkoxides to Epoxides via G3 Calculations
نویسنده
چکیده
The conformational analysis of five β-chloroand β-bromo-alkoxides had been done. The minima and the conformational transition states were determined. The anti conformer was found to be the most stable one. Its percentage is more than 99. α-Methylation increases the nuclophilicity of oxygen .Consequently, it enhances the rate of the ring closure. In contrast to βmethylation which retards the rate of the ring closure. This observation could be attributed to the reactivity of alkyl halides in SN reactions. The rearrangements of g and g conformers to carbonyl compounds are not feasible. Therefore, the main rearrangement that takes place in βhaloalkoxides is the formation of epoxides.
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