In the cyclic monoterpenes, the base-catalysed epoxidation1 of endocyclic double bonds which are in conjugation with carbonyl groups follows a highly stereoselective course resulting in a single epimer. Exocyclic double bonds are attacked from both sides in this reaction. The hydrazine hydrate reaction of epoxycarbonyl compounds (Wharton and Bohlen17) is also stereoselective resulting in allyl alcohols. The absolute configuration of ...