Palladium‐Catalyzed Cascade to Benzoxepins by Using Vinyl‐Substituted Donor–Acceptor Cyclopropanes
Matteo Faltracco, Koen N. A. van de Vrande, Martijn Dijkstra, Jordy M. Saya, Trevor A. Hamlin, Eelco Ruijter
Abstract
A palladium-catalyzed intermolecular cascade (4+3) cyclocondensation of salicylaldehydes and vinylcyclopropanes is reported. A key feature of the reaction is the use of a phosphonate group as an acceptor moiety on the cyclopropane, exploiting its propensity to undergo olefination with aldehydes. Subsequent O-allylation enabled the formation of a range of substituted benzoxepinsWith a novel chiral ligand, the products were obtained in generally good yield and with reasonable enantioselectivity.
Topics & Concepts
CyclopropaneMoietyPhosphonatePalladiumChemistryCatalysisLigand (biochemistry)AcceptorYield (engineering)Intermolecular forceCascadeCombinatorial chemistryOrganic chemistryMedicinal chemistryRing (chemistry)MoleculeMaterials sciencePhysicsChromatographyReceptorBiochemistryMetallurgyCondensed matter physicsCyclopropane Reaction MechanismsCatalytic Alkyne ReactionsCatalytic C–H Functionalization Methods