The endocyclic C᎐ ᎐ C bond of 3-allyltetronic acid 1 can be selectively oxidised with dimethyldioxirane to give 3-allyl-3hydroxydihydrofuran-2,4-dione 2 while 3-exo-alkylidenedihydrofuran-2,4-diones 9 are rapidly autooxidised to furnish the spirotricyclic hemiketal endoperoxide lactones 10. Scheme 2 Normal side-chain epoxidation of 3-allyltetronate 5: a) DMD, Ϫ78 ЊC → rt, 12 h; b) MCPBA, CHCl 3 , NaHCO 3 , rt, 12 h. Scheme 3 Formation and reductive ring opening of endoperoxides 10.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.