Dinuclear lanthanide complexes supported by a hybrid salicylaldiminato/calix[4]arene-ligand: synthesis, structure, and magnetic and luminescence properties of (HNEt3)[Ln2(HL)(L)] (Ln = SmIII, EuIII, GdIII, TbIII). Issue 12 (28th February 2019)

• Record Type: Journal Article
• Authors: Ullmann, Steve; Hahn, Peter; Blömer, Laura; Mehnert, Anne; Laube, Christian; Abel, Bernd; Kersting, Berthold
• Is Part Of: Dalton transactions. Volume 48:Issue 12(2019)
• Page Start: 3893
• Page End: 3905
• Publication Date: 2019-02-28
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/c9dt00292h
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : Salicylaldimine/calix[4]arenes support dinuclear, triply bridged, luminescent, lanthanide complexes. Abstract : The synthesis, structures, and properties of a new calix[4]arene ligand with an appended salicylaldimine unit (H4 L = 25-[2-((2-methylphenol)imino)ethoxy]-26, 27, 28-trihydroxy-calix[4]arene) and four lanthanide complexes (HNEt3 )[Ln2 (HL)(L)] (Ln = Sm III (4 ), Eu III (5 ), Gd III (6 ), and Tb III (7 )) are reported. X-ray crystallographic analysis (for4 and6 ) reveals an isostructural series of dimeric complexes with a triply-bridged NO3 Ln(μ-O)2 (OH⋯O)LnO3 N core and two seven coordinated lanthanide ions. According to UV-vis spectrometric titrations in MeCN and ESI-MS the dimeric nature is maintained in solution. The apparent stability constants range between log K = 5.8 and 6.3. The appended salicylaldimines sensitize Eu III and Tb III emission ( λ exc 311 nm) in the solid state or immersed in a polycarbonate glass at 77 K (for5, 7 ) and at 295 K (for7 ).