trans-2,8-Dioxabicyclodecanes were prepared in high yield with the creation of up to three stereocenters in a single pot by the acid-mediated reaction of γ,δ-unsaturated alcohols with aldehydes (see scheme, Bn=benzyl). This versatile reaction enables the stereoselective introduction of substituents at the C3, C4, C7, and C9 positions of the bicyclic framework.
This paper describes the reactions of N-salicylideneamines with diarylketenes generated from thermal decomposition of the 2-diazo-1,2-diarylethanones. An equimolar reaction of the Nsalicylidenebenzhydrylamine with diphenylketene affords a mixture of 2-[(benzhydrylimino)methyl]phenyl-2,2-diphenylacetate as a major product and 1-benzhydryl-3,3-diphenyl-4-[2'-(O-diphenylacyl)hydroxyphenyl]-2-azetidinone as a minor product. The reactions of various N-salicylideneamines with 2.2 molar equivalents of 2-diazo-1,2-diarylethanones have been carried out to afford 1-substituted-3,3-diaryl-4-[2'-(O-diarylacyl)hydroxyphenyl]-2-azetidinones as sole product in excellent yields. The products, characterized on the basis of satisfactory analytical and spectral data, have shown moderate to good antimicrobial activity against some bacteria and fungi. Among the fourteen compounds in the series, the 2-azetidinone 4l with a 4-chlorophenyl group on β-lactam ring nitrogen and 4-methylphenyl groups on β-lactam ring C-3 position is the most active compound.
a single pot. This approach is versatile and enables substituents to be introduced at the C3, C4, C7, and C9 positions of the bicyclic framework with excellent stereocontrol.
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.