Details

Autor(en) / Beteiligte

• Kokina, Tatyana E
• Rakhmanova, Marianna I
• Shekhovtsov, Nikita A
• Glinskaya, Ludmila A
• Komarov, Vladislav Y
• Agafontsev, Alexander M
• Baranov, Andrey Y
• Plyusnin, Pavel E
• Sheludyakova, Liliya A
• Tkachev, Alexey V
• Bushuev, Mark B

Titel

Luminescent Zn() and Cd() complexes with chiral 2,2′-bipyridine ligands bearing natural monoterpene groups: synthesis, speciation in solution and photophysics

Ist Teil von

• Dalton transactions : an international journal of inorganic chemistry, 2020-06, Vol.49 (22), p.7552-7563

Ort / Verlag

England: Royal Society of Chemistry

Erscheinungsjahr

2020

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Mononuclear zinc( ii ) and cadmium( ii ) complexes, ZnLCl 2 ( 1 ), CdLCl 2 ( 2 ), ZnL 1 Cl 2 ·2H 2 O ( 3 ), and CdL 1 Cl 2 ·2H 2 O ( 4 ), with chiral ligands containing a 2,2′-bipyridine moiety and natural terpene (+)-limonene ( L ) or (+)-3-carene ( L 1 ) moieties were synthesized. In these complexes the L and L 1 ligands are shown to coordinate Zn 2+ and Cd 2+ ions through the 2,2′-bipyridine moiety. The acetamide group of the ligands interacts with M 2+ ions by forming N M 2+ and C&z.dbd;O M 2+ contacts and N-H Cl hydrogen bonds with coordinated Cl − ions. In solutions the complexes have several conformers differing by the degree of the turn of the acetamide moiety relative to the ligand core and the type of its interaction with the coordination core. The ligands and complexes exhibit luminescence with the quantum yield increasing in the order: ligand < cadmium( ii ) complex < zinc( ii ) complex. The complexes 3 and 4 demostrate excitation wavelength independent single-channel fluorescence. As opposed to 3 and 4 , the complexes 1 and 2 demonstrate excitation wavelength dependent emission with nanosecond and microsecond lifetimes of the excited states. According to our TD-DFT calculations, an interplay of ligand centered and halide to ligand transitions facilitates two deactivation channels in 1 and 2 : S 1 -S 0 and T 1 -S 0 . Coordination of chiral ligands containing a 2,2′-bipyridine moiety and natural terpene (+)-limonene or (+)-3-carene groups to zinc( ii ) and cadmium( ii ) leads to excitation wavelength dependent emission.