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Title: A Pyridine–Pyridine Cross‐Coupling Reaction via Dearomatized Radical Intermediates
Abstract

A pyridine–pyridine coupling reaction has been developed between pyridyl phosphonium salts and cyanopyridines using B2pin2as an electron‐transfer reagent. Complete regio‐ and cross‐selectivity are observed when forming a range of valuable 2,4′‐bipyridines. Phosphonium salts were found to be the only viable radical precursors in this process, and mechanistic studies indicate that the process does not proceed through a Minisci‐type coupling involving a pyridyl radical. Instead, a radical–radical coupling process between a boryl phosphonium pyridyl radical and a boryl‐stabilized cyanopyridine radical explains the C−C bond‐forming step.

 
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NSF-PAR ID:
10115073
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie
Volume:
131
Issue:
42
ISSN:
0044-8249
Page Range / eLocation ID:
p. 15024-15028
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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