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Abstract The first enantiopure chiral‐at‐rhenium complexes of the formfac‐ReX(CO)3(:C^N) have been prepared, where :C^N is a helicene‐N‐heterocyclic carbene (NHC) ligand and X=Cl or I. These have complexes show strong changes in the emission characteristics, notably strongly enhanced phosphorescence lifetimes (reaching 0.7 ms) and increased circularly polarized emission (CPL) activity, as compared to their parent chiral models lacking the helicene unit. The halogen along with its position within the dissymmetric stereochemical environment strongly affect the photophysics of the complexes, particularly the phosphorescence quantum yield and lifetime. These results give fresh insight into fine tuning of photophysical and chiroptical properties of Re‐NHC systems.
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Modulation of Chiroptical and Photophysical Properties in Helicenic Rhenium(I) Systems: The Use of an N ‐(Aza[6]helicenyl)‐NHC Ligand
Abstract The photophysical and chiroptical properties of a novel, chiral helicene‐NHC−Re(I) complex bearing anN‐(aza[6]helicenyl)‐benzimidazolylidene ligand are described, showing its ability to emit yellow circularly polarized luminescence. A comparative analysis of this new system with other helicene‐Re(I) complexes reported to date illustrates the impact of structural modifications on the emissive and absorptive properties.
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- Award ID(s):
- 2152633
- PAR ID:
- 10401158
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 29
- Issue:
- 21
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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