Reactivite des epoxydes—III: Methodes de synthese d'hydroxyalkyl-1 vinyl-2 cyclopropanes: reactions d'epoxydes γ,δ-ethyleniques avec les amidures de lithium dans l'HMTP

Abstract From the study of the reactivity of γ,δ-ethylenic epoxides in the presence of lithium amides in non polar medium (ether, hexane, benzene) the normal behaviour of these compounds is found (β-elimination). In HMPT as a solvent, a total change of reactivity is possible; γ-elimination takes place and leads to the formation of 1-hydroxyalkyl-2-vinyl cyclopropanes in high yield. Nevertheless this cyclization needs a favourable epoxide configuration to be attained, otherwise β-elimination is still observed.