title: An N-heterocyclic carbene-catalyzed [8 + 3] annulation of tropone and enals via homoenolate.
abstract: A novel protocol for the annulation of tropone to enals involving nucleophilic heterocyclic carbene (NHC) catalyzed homoenolate formation has been developed. Interestingly, the reaction led to bicyclic delta-lactones instead of the expected gamma-spirolactones, presumably by the uncommon [8 + 3] annulation pathway. The strategy works well with a variety of enals.
authors.affiliation: Organic Chemistry Section, Regional Research Laboratory (CSIR), Trivandrum 695 019, India. vijaynair_2001@yahoo.com
authors.forename: Vijay
authors.initials: V
authors.lastname: Nair
authors.forename: Manojkumar
authors.initials: M
authors.lastname: Poonoth
authors.forename: Sreekumar
authors.initials: S
authors.lastname: Vellalath
authors.forename: Eringathodi
authors.initials: E
authors.lastname: Suresh
authors.forename: Rajasekaran
authors.initials: R
authors.lastname: Thirumalai