Bright luminescent lithium and magnesium carbene complexes.
Chem Sci
; 12(21): 7401-7410, 2021 Apr 15.
Article
em En
| MEDLINE
| ID: mdl-34163830
ABSTRACT
We report on the convenient synthesis of a CNC pincer ligand composed of carbazole and two mesoionic carbenes, as well as the corresponding lithium- and magnesium complexes. Mono-deprotonation affords a rare "naked" amide anion. In contrast to the proligand and its mono-deprotonated form, tri-deprotonated s-block complexes show bright luminescence, and their photophysical properties were therefore investigated by absorption- and luminescence spectroscopy. They reveal a quantum yield of 16% in solution at ambient temperature. Detailed quantum-chemical calculations assist in rationalizing the emissive properties based on an Intra-Ligand-Charge-Transfer (ILCT) between the carbazolido- and mesoionic carbene ligands. (Earth-)alkali metals prevent the distortion of the ligand following excitation and, thus, by avoiding non-radiative deactivation support bright luminescence.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Chem Sci
Ano de publicação:
2021
Tipo de documento:
Article