Unimolecular syn-eliminations

Amine oxides can be prepared by the oxidation of the corresponding amine with an oxidant such as H2O2, Ag20 or m-CPBA (mefa-chloroperoxybenzoic acid). 

Selenoxides undergo elimination at temperatures even lower than room temperature. The Grieco elimination is an organic reaction describing the elimination reaction of an aliphatic primary alcohol through a selenide to a terminal alkene. 

Carbon-Carbon Double Bond Forming Reactions 

The potassium xanthate salts of some tertiary alcohols on pyrolysis yield alkenes. The overall yield in this case is often markedly better than those obtained from the corresponding 5-methyl xanthates (the classical Chugaev procedure). 

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