Bi:cyclic terpene epoxide cpds. prodn. - by reacting terpene(s) e.g. alpha-pinene with technical peracetic acid in presence of acid binding and chlorinated solvent e.g. chloroform

摘要

Prodn. of bicyclic terpene oxiranes by epoxidation of unsatd. terpene hydrocarbons with peracetic acid/acetic acid mixts. still contg. water, H2O2 and (possibly) small amts. of H2SO4 in the presence of acid binding agents, the epoxidation is carried out in an inert 1-3C aliphatic hydrocarbon, having -CCl3-, -CHCl2-, -CH2Cl-, -CHCl- or -CCL2- gps. The acid binding agent is pref. an alkali (bi)-carbonate used in solid form in an amt. of 0.3-0.7 or 0.6-1.4 mol per mol acid acid content of the peracetic acid mixt. Bicyclic terpene epoxides are highly reactive substances useful as synthetic intermediates. Thus rearrangement of alpha-pinene epoxide in the presence of ZnBr2 gives e.g. campholene aldehyde, a precursor of perfumes and softening agents. Hydrolysis of alpha-pinene epoxide gives sobrerol, a therapeutically active substance which can be used in pharmaceutical compositions. Conversion of the terpene is high, and the terpene oxiranes are obtd. in excellent to almost quantitative yield.