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Title: Mono‐ and Bis‐Alkynyl Iron Complexes Supported by a “Softened” Tetraaza Macrocycle
Abstract

A pair of novel Fe‐alkynyl complexes, [FeIII(HMTI)(C2SiEt3)2]ClO4(2) and [FeII(HMTI)(C2SiEt3)(NCCH3)]ClO4(3), is described herein. Reaction of Fe(meso‐HMC)Cl(ClO4)]ClO4(1) with lithiated triethylsilylacetylene and subsequent exposure to oxygen yielded the bis‐alkynyl2containing the dehydrogenated tetraimine macrocycle (HMTI). Reduction of2by mossy zinc in acetonitrile yielded the mono‐alkynyl3. The structures of2and3were determined using single‐crystal X‐ray diffraction. Analysis of visible absorption and electrochemical data establishes the redox‐active nature of the HMTI macrocycle, and indicates significant interactions between the Fedπ and tetraimine π* orbitals. These deductions are further supported by density functional theory calculations.

 
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Award ID(s):
2102049
NSF-PAR ID:
10363764
Author(s) / Creator(s):
 ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
European Journal of Inorganic Chemistry
Volume:
2022
Issue:
7
ISSN:
1434-1948
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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