A novel methodology to transform bisallenes into a variety of polycyclic derivatives employing rhodium(I) catalysis has been developed. This transformation encompasses an intramolecular Rh-catalyzed cycloisomerization of bisallenes 1 to deliver a reactive cycloheptadiene, which concomitantly undergoes a regioselective [4 + 2] cycloaddition with alkenes. A complete mechanistic study of this transformation has been undertaken including DFT calculations. Overall, the methodology presented here constitutes a new and straightforward entry to polycyclic dihydroazepine and dihydrooxepine derivatives employing catalytic methods.
The paper was published recently in Organic Letters by Agustí Lledó, Miquel Solà, Anna Pla and Anna Roglans
A. Artigas, J. Vila, A. Lledó, M. Solà, A. Pla-Quintana, and A. Roglans
“A Rh-Catalyzed Cycloisomerization/Diels–Alder Cascade Reaction of 1,5-Bisallenes for the Synthesis of Polycyclic Heterocycles”
Org. Lett.2019, 21, 6608-6613
DOI: 10.1021/acs.orglett.9b02032
www.dx.doi.org/10.1021/acs.orglett.9b02032
and includes the Cover!
