76015-70-8Relevant academic research and scientific papers
11,13-METHYLENATION OF SESQUITERPENE EXOMETHYLENE-&γ-LACTONES: SYNTHESIS OF SESQUITERPENE CYCLOPROPYL-&γ-LACTONES
Appendino, Giovanni,Ghilardi, Elisabetta,Cravotto, Giancarlo,Gariboldi, Pierluigi
, p. 1052 - 1063 (2007/10/02)
11,13-Methylene derivatives of sesquiterpene exomethylene-γ-lactones were prepared by reaction of diazomethane and photolysis of the resulting pyrazoline adduct(s).Variable amounts of exomethylene- and ethylidene-γ-lactones were also formed in the photolysis reaction.These compounds could be removed after reaction with diethylamine and chromatography on a bilayer (basic alumina/silica gel) column.Also 11,13-methylene derivatives of acid- and thermolabile germacranolides could be prepared in good yield with this procedure.Results obtained using alternative methods of methylenation are reported.A comparative study of the reactivity towards nucleophiles of exomethylene- and cyclopropyl sesquiterpene-γ-lactones provided little support for the involvement of compounds of the latter class in "in vivo" alkylation reactions.
