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Asymmetric Allylic Alkylation with Deconjugated Carbonyl Compounds: Direct Vinylogous Umpolung Strategy
Author(s) -
Ran GuangYao,
Yang XingXing,
Yue JingFei,
Du Wei,
Chen YingChun
Publication year - 2019
Publication title -
angewandte chemie
Language(s) - English
Resource type - Journals
eISSN - 1521-3757
pISSN - 0044-8249
DOI - 10.1002/ange.201903478
Subject(s) - umpolung , chemistry , tsuji–trost reaction , alkylation , allylic rearrangement , regioselectivity , tautomer , chirality (physics) , enantioselective synthesis , phosphonium , catalysis , combinatorial chemistry , stereochemistry , organic chemistry , nucleophile , nambu–jona lasinio model , chiral symmetry breaking , physics , quantum mechanics , quark
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.