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Title: General method for iron-catalyzed multicomponent radical cascades–cross-couplings
Transition metal–catalyzed cross-coupling reactions are some of the most widely used methods in chemical synthesis. However, despite notable advantages of iron (Fe) as a potentially cheaper, more abundant, and less toxic transition metal catalyst, its practical application in multicomponent cross-couplings remains largely unsuccessful. We demonstrate 1,2-bis(dicyclohexylphosphino)ethane Fe–catalyzed coupling of α-boryl radicals (generated from selective radical addition to vinyl boronates) with Grignard reagents. Then, we extended the scope of these radical cascades by developing a general and broadly applicable Fe-catalyzed multicomponent annulation–cross-coupling protocol that engages a wide range of π-systems and permits the practical synthesis of cyclic fluorous compounds. Mechanistic studies are consistent with a bisarylated Fe(II) species being responsible for alkyl radical generation to initiate catalysis, while carbon-carbon bond formation proceeds between a monoarylated Fe(II) center and a transient alkyl radical.  more » « less
Award ID(s):
1751568
NSF-PAR ID:
10316909
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Science
Volume:
374
Issue:
6566
ISSN:
0036-8075
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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