Catalytic Asymmetric [8+2] Annulation Reactions Promoted by a Recyclable Immobilized Isothiourea
作者:Shoulei Wang、Carles Rodríguez-Escrich、Miquel A. Pericàs
DOI:10.1002/anie.201707341
日期:2017.11.20
enriched cycloheptatrienes fused to a pyrrolidone ring on the basis of an isothiourea‐catalyzed periselective [8+2] cycloadditionreaction between chiral ammonium enolates (generated in situ from carboxylic acids) and azaheptafulvenes. The resulting bicyclic compounds can be hydrogenated, but, most remarkably, they can also undergo completely regioselective [4+2] cycloaddition with active dienophiles to
Formation of Dihydroaza-azulanones Possessing Spirocyclic Moieties: [8+2] Type Cycloaddition Reactions of Iminotropones to an Exocyclic Double Bond of 8-Oxoheptafulvene