Iodobenzene catalysed synthesis of spirofurans and benzopyrans by oxidative cyclisation of vinylogous esters
作者:Marsewi Ngatimin、Raphael Frey、Cecily Andrews、David W. Lupton、Oliver E. Hutt
DOI:10.1039/c1cc15015d
日期:——
Vinylogous esters bearing para or meta methoxy benzyl groups undergo oxidativecyclisation with 5-20 mol% iodobenzene and m-CPBA to give spirofuran or benzopyran containing heterocycles. The reaction allows rapid generation of skeletal complexity in good to excellent yields via a noveloxidativecyclisation.
Photoinduced electron transfer (PET) reactions of α-cyclopropyl-substituted ketones and triethylamine (TEA) were used to initiate the cyclopropylcarbinyl-homoallyl rearrangement. The intramolecular cyclization reaction onto triple bonds was performed yielding bicyclic and spirocyclic compounds. Furthermore, in some preliminary studies it was shown that even intramolecular aromatic substitutions are
Iodobenzene-Catalyzed Oxabicyclo[3.2.1]octane and [4.2.1]Nonane Synthesis via Cascade C–O/C–C Formation
作者:Marsewi Ngatimin、Raphael Frey、Alison Levens、Yuji Nakano、Marcin Kowalczyk、Kristina Konstas、Oliver E. Hutt、David W. Lupton
DOI:10.1021/ol4029308
日期:2013.11.15
via C–C and C–O bond formation has been achieved with electron rich aromatic groups and vinylogous esters acting as independent nucleophiles. The reaction provides oxabicyclo[3.2.1]octanes and [4.2.1]nonanes from commercially available 3-alkoxy cycohexen-2-ones in three steps.