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Title: Bimetallic, Silylene‐Mediated Multielectron Reductions of Carbon Dioxide and Ethylene
Abstract

A metal/ligand cooperative approach to the reduction of small molecules by metal silylene complexes (R2Si=M) is demonstrated, whereby silicon activates the incoming substrate and mediates net two‐electron transformations by one‐electron redox processes at two metal centers. An appropriately tuned cationic pincer cobalt(I) complex, featuring a central silylene donor, reacts with CO2to afford a bimetallic siloxane, featuring two CoIIcenters, with liberation of CO; reaction of the silylene complex with ethylene yields a similar bimetallic product with an ethylene bridge. Experimental and computational studies suggest a plausible mechanism proceeding by [2+2] cycloaddition to the silylene complex, which is quite sensitive to the steric environment. The CoII/CoIIproducts are reactive to oxidation and reduction. Taken together, these findings demonstrate a strategy for metal/ligand cooperative small‐molecule activation that is well‐suited to 3dmetals.

 
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Award ID(s):
1552591 1919571
NSF-PAR ID:
10236177
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
60
Issue:
3
ISSN:
1433-7851
Page Range / eLocation ID:
p. 1615-1619
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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