Synthesis of homodinuclear lanthanide(III) complexes of 24-membered tetraaza and 34-membered octaaza Schiff base macrocycles

• Published in: Polyhedron Vol. 18; no. 24; pp. 3123 - 3128
• Main Authors: Kumar, D.Suresh, Aruna, V.Arul Joseph, Alexander, V.
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 01.01.1999; Elsevier
• Subjects: Chemistry; Chemistry, Inorganic & Nuclear; Crystallography; Dinuclear lanthanide macrocycles; Imine–phenol macrocycles; Luminescent lanthanide macrocycles; Physical Sciences; Schiff base macrocycles; Science & Technology; Luminescent lanthanide macrocycles; Dinuclear lanthanide macrocycles; Imine–phenol macrocycles; Schiff base macrocycles; DESIGN; imine-phenol macrocycles; LUMINESCENCE; LIGANDS; luminescent lanthanide macrocycles; DYNAMICS; dinuclear lanthanide macrocycles; ACTINIDES; IONS; METAL-COMPLEXES
• ISSN: 0277-5387
• DOI: 10.1016/S0277-5387(99)00232-6

Homodinuclear lanthanide(III) complexes [Ln 2(H 2L 4)(NO 3) 2(CH 3CN)](NO 3) 2· nH 2O (Ln=La, Eu, Gd, Tb or Dy; n=3, 4 or 5) of the 24-membered tetraimine phenolic macrocycle 15,31-dimethyl-7,23-dinitro-3,11,19,27-tetraazapentacyclo[27.3.1.1 13,17.1 5,9.1 21,25]hexatriaconta-1(33),2,5,7,9(35),11,13,15,17(34),18,21,23,25(36),27,29,31-hexadecaene-33,34,35,36-tetraol (H 4L 4), have been synthesized by the condensation of 2,6-diformyl-4-methylphenol and 2,6-bis(aminomethyl)-4-nitrophenol in the presence of hydrated lanthanide(III) nitrates. For the 34-membered octaaza macrocycle, 18,37-dimethyl-3,7,10,14,22,26,29,33-octaazatricyclo[33.3.1.1 16,20]tetraconta-1(39),2,14,16,18,20(40),21,33,35,37-decaene-39,40-diol (H 2L 5), the complexes [Ln 2(H 2L 5)(NO 3) x (H 2O) y ](NO 3) z · nH 2O (Ln=La, Pr, Nd, Sm, Eu, Gd or Dy; x=3 or 4; y=0 or 1; z=2 or 3; n=1–4) and [Ln 2(L 5)(NO 3) x ](NO 3) y · nH 2O (Ln=Tb, Ho or Er; x=2 or 3; y=1 or 2; n=1 or 2) have been synthesized by the condensation of 2,6-diformyl-4-methylphenol with 1,2-bis(3-aminopropylamino)ethane in the presence of hydrated lanthanide(III) nitrates. The dinuclear Eu(III) complexes exhibit electronic energy transfer from the ligand to the metal centers resulting in the enhancement of the Eu(III) emission.