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Title: Dinuclear Rhenium Complexes with a Bridging Helicene‐bis‐bipyridine Ligand: Synthesis, Structure, and Photophysical and Chiroptical Properties
Abstract

By attaching pyridine groups to a diaza[6]helicene, a helical, bis‐ditopic, bis‐NN‐coordinating ligand can be accessed. Dinuclear rhenium complexes featuring this bridging ligand, of the form [{Re(CO)3Cl}2(NNNN)], have been prepared and resolved to give enantiopure complexes. These complexes are phosphorescent in solution at room temperature under one‐ and two‐photon excitation. Their experimental chiroptical properties (optical rotation, electronic circular dichroism and circularly polarized emission) have been measured. They show, for instance, emission dissymmetry factors of c.a. ±3x10−3. Quantum‐chemical calculations indicate the importance of stereochemistry on the optical activity, pointing towards further design improvements in such types of complexes.

 
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Award ID(s):
1855470
NSF-PAR ID:
10238440
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
ChemPlusChem
Volume:
85
Issue:
11
ISSN:
2192-6506
Page Range / eLocation ID:
p. 2446-2454
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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