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Title: Lewis Acid Supported Nickel Nitrenoids
Abstract

Metalation of the polynucleating ligandF,tbsLH6(1,3,5‐C6H9(NC6H3−4‐F−2‐NSiMe2tBu)3) with two equivalents of Zn(N(SiMe3)2)2affords the dinuclear product (F,tbsLH2)Zn2(1), which can be further deprotonated to yield (F,tbsL)Zn2Li2(OEt2)4(2). Transmetalation of2with NiCl2(py)2yields the heterometallic, trinuclear cluster (F,tbsL)Zn2Ni(py) (3). Reduction of3with KC8affords [KC222][(F,tbsL)Zn2Ni] (4) which features a monovalent Ni centre. Addition of 1‐adamantyl azide to4generates the bridging μ3‐nitrenoid adduct [K(THF)3][(F,tbsL)Zn2Ni(μ3‐NAd)] (5). EPR spectroscopy reveals that the anionic cluster possesses a doublet ground state (S=). Cyclic voltammetry of5reveals two fully reversible redox events. The dianionic nitrenoid [K2(THF)9][(F,tbsL)Zn2Ni(μ3‐NAd)] (6) was isolated and characterized while the neutral redox isomer was observed to undergo both intra‐ and intermolecular H‐atom abstraction processes. Ni K‐edge XAS studies suggest a divalent oxidation state for the Ni centres in both the monoanionic and dianionic [Zn2Ni] nitrenoid complexes. However, DFT analysis suggests Ni‐borne oxidation for5.

 
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Award ID(s):
1834750
NSF-PAR ID:
10473391
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
62
Issue:
50
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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    Metalation of the polynucleating ligandF,tbsLH6(1,3,5‐C6H9(NC6H3−4‐F−2‐NSiMe2tBu)3) with two equivalents of Zn(N(SiMe3)2)2affords the dinuclear product (F,tbsLH2)Zn2(1), which can be further deprotonated to yield (F,tbsL)Zn2Li2(OEt2)4(2). Transmetalation of2with NiCl2(py)2yields the heterometallic, trinuclear cluster (F,tbsL)Zn2Ni(py) (3). Reduction of3with KC8affords [KC222][(F,tbsL)Zn2Ni] (4) which features a monovalent Ni centre. Addition of 1‐adamantyl azide to4generates the bridging μ3‐nitrenoid adduct [K(THF)3][(F,tbsL)Zn2Ni(μ3‐NAd)] (5). EPR spectroscopy reveals that the anionic cluster possesses a doublet ground state (S=). Cyclic voltammetry of5reveals two fully reversible redox events. The dianionic nitrenoid [K2(THF)9][(F,tbsL)Zn2Ni(μ3‐NAd)] (6) was isolated and characterized while the neutral redox isomer was observed to undergo both intra‐ and intermolecular H‐atom abstraction processes. Ni K‐edge XAS studies suggest a divalent oxidation state for the Ni centres in both the monoanionic and dianionic [Zn2Ni] nitrenoid complexes. However, DFT analysis suggests Ni‐borne oxidation for5.

     
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