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Title: Unusual Enantiodivergence in Chiral Brønsted Acid‐Catalyzed Asymmetric Allylation with β‐Alkenyl Allylic Boronates
Abstract

We report herein a rare example of enantiodivergent aldehyde addition with β‐alkenyl allylic boronates via chiral Brønsted acid catalysis. 2,6‐Di‐9‐anthracenyl‐substituted chiral phosphoric acid‐catalyzed asymmetric allylation using β‐vinyl substituted allylic boronate gave alcohols withRabsolute configuration. The sense of asymmetric induction of the catalyst in these reactions is opposite to those in prior reports. Moreover, in the presence of the same acid catalyst, the reactions with β‐2‐propenyl substituted allylic boronate generated homoallylic alcohol products withSabsolute configuration. Unusual substrate‐catalyst C−H⋅⋅⋅π interactions in the favoured reaction transition state were identified as the origins of observed enantiodivergence through DFT computational studies.

 
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Award ID(s):
1764328 2153972 2042353
NSF-PAR ID:
10373663
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
61
Issue:
41
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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