In:
Angewandte Chemie International Edition, Wiley, Vol. 58, No. 27 ( 2019-07), p. 9210-9214
Kurzfassung:
An atom‐economic and highly efficient vinylogous umpolung strategy is developed for deconjugated carbonyl compounds, which generate electron‐deficient π‐allylpalladium complexes with Pd(OAc) 2 under ligand‐free conditions. In cooperation with a chiral‐phosphonium‐based phase‐transfer catalyst, the asymmetric direct oxidative allylic alkylations of 3‐substituted oxindoles are furnished under O 2 atmosphere. The γ‐ or even remote ϵ‐regioselective alkylation products, with substantial substituents, are delivered with excellent enantioselectivity, and can be further used to access diverse chiral spirocyclic architectures effectively. The Mukaiyama dienol silyl ether can be utilized similarly, indicating that the current active π‐allylpalladium species results from tautomerization of the Pd II ‐dienolate intermediate.
Materialart:
Online-Ressource
ISSN:
1433-7851
,
1521-3773
DOI:
10.1002/anie.201903478
Sprache:
Englisch
Verlag:
Wiley
Publikationsdatum:
2019
ZDB Id:
2011836-3
ZDB Id:
123227-7