An efficient methodology has been developed for the synthesis of tetra-and pentasubstituted pyrroles via oxidative self-dimerization of N-propargylamines catalyzed by silver benzoate in the presence of K 2 S 2 O 8 in good yields. The protocol provides a simple route for the synthesis of both tetra-and pentasubstituted pyrroles with two carbonyl groups in the side chain. The methodology can be extended toward the synthesis of pyrrolo- [3,4-d]pyridazine.
Bismuth trifluoromethanesulfonate can be efficiently used for the preparation of dihydropyrans from βallenols and aldehydes by oxonium−ene reaction in good yields. The reaction is highly regioselective. On the other hand, the same reaction with trimethylsilyl trifluoromethanesulfonate at −45 °C affords the hexahydropyrano[4,3-b]pyran skeleton in moderate yields.
Hexahydrofuro[3,4-b]furan-4-ol and its dimer can conveniently be synthesized from ((4S,5R)-2,2-dimethyl-5-vinyl-1,3-dioxolan-4-yl)methanol and aldehydes in good yields with excellent diastereo- and enantio-selectivity.
Intramolecular hydroalkoxylation of alkenols mediated by boront rifluoride etherate leads to substituted fivemembered tetrahydrofurans and six-memberedt etrahydropyrans in good yields.
Hexahydrobenzo[de]isochromanes and hexahydropyrano[3,4,5-ij]isoquinolines can be efficiently synthesized via Friedel Crafts and oxa Pictet-Spengler reaction of acrylyl enol ethers mediated by triflic acid in good yields. The reaction is highly stereoselective. Two of the hexahydrobenzo[de]isochromanes are found to have moderate antileishmanial activity.
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.