ELECTROPHILIC CYCLIZATION OF ALPHA-GERANYL AND BETA-GERANYL ACETATES BY MERCURY(II) TRIFLUOROACETATE

Electrophilic cyclization of beta-geranyl acetate promoted by mercury( II) trifluoroacetate leads to mixtures of alpha- and gamma-5 alpha H-c yclogeranyl acetate derivatives and 6 alpha-hydroxy-5 alpha H- and 6 a lpha-hydroxy-5 beta H-cyclogeranyl acetate derivatives mercurated at t he C-3 atom. The ratio of the unsaturated and hydroxymercurated produc ts depends on the reaction conditions. alpha-Geranyl acetate reacts wi th mercury(II) trifluoroacetate to give a mixture of 6 alpha-hydroxy-5 alpha H- and 6 alpha-hydroxy-5 beta H-geranyl acetates, mercurated at C-9, with an equatorial mercurated methylene group at C-4. The mercur y-containing groups in mercurated cyclogeranyl derivatives can easily be reduced or replaced by an oxygen-containing functional group; this constitutes a convenient route to polyfunctional cyclogeranyl derivati ves that are difficult to obtain.