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The photophysical and chiroptical properties of a novel, chiral helicene‐NHC−Re(I) complex bearing an N‐(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. [ABSTRACT FROM AUTHOR]

The first enantiopure chiral‐at‐rhenium complexes of the form fac‐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. [ABSTRACT FROM AUTHOR]

The first enantiopure chiral‐at‐rhenium complexes of the form fac‐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. [ABSTRACT FROM AUTHOR]

Frontispiz: Long-Lived Circularly Polarized Phosphorescence in Helicene-NHC Rhenium(I) Complexes: The Influence of Helicene, Halogen, and Stereochemistry on Emission Properties Keywords: circularly polarized emission; helicenes; N-heterocyclic carbenes; phosphorescence; rhenium(I) EN circularly polarized emission helicenes N-heterocyclic carbenes phosphorescence rhenium(I) 1 1 1 05/18/20 20200525 NES 200525 B Chiroptische Verbindungen b In ihrer Zuschrift auf S. 8472 beschreiben J. A. G. Williams, J. Autschbach, J. Crassous et al. die Synthese von Rhenium(I)/NHC-Helicen-Komplexen mit zirkular polarisierter Phosphoreszenz sowie photophysikalische Untersuchungen dieser Verbindungen. Circularly polarized emission, helicenes, N-heterocyclic carbenes, phosphorescence, rhenium(I). [Extracted from the article]

Innentitelbild: Long-Lived Circularly Polarized Phosphorescence in Helicene-NHC Rhenium(I) Complexes: The Influence of Helicene, Halogen, and Stereochemistry on Emission Properties (Angew. Keywords: circularly polarized emission; helicenes; N-heterocyclic carbenes; phosphorescence; rhenium(I) EN circularly polarized emission helicenes N-heterocyclic carbenes phosphorescence rhenium(I) 8382 8382 1 05/18/20 20200525 NES 200525 B Zeitaufgelöste impulsive b stimulierte Raman-Spektroskopie, eine ultraschnelle Raman-Technik, ermöglicht es, Momentaufnahmen von Molekülen im angeregten Zustand mit hoher Empfindlichkeit und Zeitauflösung zu gewinnen. Circularly polarized emission, helicenes, N-heterocyclic carbenes, phosphorescence, rhenium(I). [Extracted from the article]