Chiral Emissive Lanthanide Complexes from Enantiopure [6]Helicene‐bis(pyrazolyl)‐pyridine Ligands. Issue 11 (22nd February 2022)

• Record Type: Journal Article
• Authors: Abhervé, Alexandre; Mastropasqua Talamo, Maurizio; Vanthuyne, Nicolas; Zinna, Francesco; Di Bari, Lorenzo; Grasser, Maxime; Le Guennic, Boris; Avarvari, Narcis
• Is Part Of: European journal of inorganic chemistry. Volume 2022:Issue 11(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-02-22
• Subjects: Circular dichroism -- Circularly polarized luminescence -- Helicenes -- Lanthanide complexes -- N ligands; Chemistry, Inorganic -- Periodicals; Organometallic chemistry -- Periodicals; Bioinorganic chemistry -- Periodicals; Solid state chemistry -- Periodicals; 546
• DOI: 10.1002/ejic.202200010
• Languages: English
• ISSNs: 1434-1948

Abstract

Abstract: Enantiopure helicene‐based bis(pyrazol‐1‐yl)pyridine (bpp‐[6]helicene), with the helicene unit in position 4 of the pyridine ring, have been prepared and structurally characterized. Their chiroptical properties have been studied experimentally, and both absorption and circular dichroism (CD) spectra have been reproduced theoretically by time‐dependent density functional theory (TDDFT). Remarkably, in spite of the remote localization of the helicene with respect to the coordination pocket of the bpp motif, chiral Eu(III) complexes based on these ligands show, however, circularly polarized luminescence in the visible region, sustained by TDDFT and CASSCF calculations, which also emphasize the possible antenna effect of the bpp ligand. Abstract : The use of enantiopure bis(pyrazolyl)‐pyridine‐[6]helicene ligands allowed the preparation of chiral emissive Eu(III) and Yb(III) complexes. Remarkably, the Eu(III) complex shows CPL activity despite the remote position of the helicene unit with respect to the coordination sphere of the metal ion.