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Title: Palladium‐Catalyzed Allylic Alkylation of 2‐Aryl‐1,3‐Dithianes, an Umpolung Synthesis of β,γ‐Unsaturated Ketones
Abstract

Palladium‐catalyzed allylic alkylation of 2‐aryl‐1,3‐dithianes at room temperature is described. A variety of cyclic and acyclic electrophiles successfully coupled within‐situgenerated 2‐sodio‐1,3‐dithiane nucleophiles to afford the allylated products in good to excellent yields (25 examples). Deprotection of these products leads to valuable β,γ‐unsaturated ketones. Direct synthesis of such β,γ‐unsaturated ketones via a one‐pot allylation‐oxidation protocol is also presented. Investigation into the stereochemistry of the allylation reaction revealed that the 2‐sodio‐1,3‐dithiane nucleophile behaves as a “soft” nucleophile, which underwent external attack on the π‐allyl palladium complex to provide retention of stereochemistry (double inversion pathway). Additionally, the utility of this method was demonstrated through a sequential one‐pot allylation‐Heck cyclization to produce asterogynin derivatives, which are important bioactive compounds in medicinal chemistry.

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NSF-PAR ID:
10080458
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Synthesis & Catalysis
Volume:
361
Issue:
3
ISSN:
1615-4150
Page Range / eLocation ID:
p. 502-509
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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