An N-heterocyclic carbene-catalyzed [8 + 3] annulation of tropone and enals via homoenolate.
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.
Nair
Vijay
V
Organic Chemistry Section, Regional Research Laboratory (CSIR), Trivandrum 695 019, India. vijaynair_2001@yahoo.com
Poonoth
Manojkumar
M
Vellalath
Sreekumar
S
Suresh
Eringathodi
E
Thirumalai
Rajasekaran
R