Dinuclear and tetranuclear copper(II) complexes with bridging (N–N) diazine ligands: variable magnetic exchange topologies †

Crystal Structure and Photoluminescence Properties of One Two-Dimensional Coordination Polymer [Ag2L1.5(NO3)2(CH3CN)]n (L = N,N′-Bis(furan-2-ylmethylene)hydrazine)

“…In addition, the sheets are further aggregated to the threedimensional state by the C (1) (7) 146 -x, -y, 1 -z C(9)−H(9)···O (5) 0.93 2.56 3.380(8) 148…”

“…[1][2][3][4] Among them, diazine Schiffbase ligands with two coordination portions linked by a single N−N bridge are excellent ligands, which are easy to prepare and inexpensive, allowing us to systematically probe the effect of modifications to the ligand backbone through which we are attempting to control the precise topography, or microarchitecture, of the arrays. [3][4][5][6][7][8][9][10][11][12][13][14][15] Herein the chosen ligand, N,N -bis(furan-2-ylmethylene)hydrazine L, with two furanylimine sites connected by a single bond, is one of the simplest imine-based ligands, which has been used to assemble some coordination polymers or networks such as [Ag 2 L(NO 3 ) 2 ] n , [16] [Ag 2 L 2 ](BF 4 ) 2 } n , [16] {[Ag 2 L 3 ](ClO 4 ) 2 } n , [16] {[Ag 2 L 3 ](PF 6 ) 2 } n , [16,17] [18] [Na 2 L 2 (ClO 4 ) 2 (H 2 O) 4 ], [19] and [{Ag 2 L 3 (BF 4 ) 2 } H 2 O] n . [20] Interestingly, the structural topologies of the metalorganic frameworks in self-assembly processes not only are influenced by the nature of different counteranions due to the electroneutrality principle of ligand L, but also participate in other types of factors, notably with the solvent systems.…”

New homodi-and heterotrinuclear metal complexes of Schiff base compartmental ligand: interaction studies of copper complexes with calf thymus DNA

“…In this regard, diazines in aromatic heterocyclic ligands have been utilized in bringing two copper (II) centers into close proximity to study the influence of antiferromagnetic intramolecular exchange. However, diazine linkages in open chain with N-N single bonds are much more flexible in comparison to heterocyclic ring systems [9]. Among the first row transition metal ions, manganese, cobalt, nickel and copper offer the choice of biocompatibility in biological systems and have been recognized as having important biological effects.…”

Tridentate facial coordination mode of an unsymmetrical tetradentate diazine ligand in an iron(III) complex

“…Here the two chelating sites are connected by a single bond. A number of structurally characterised cationic triple helical dinuclear complexes ([M 2 (l-pahn) 3 ] 4+ ) have been reported with the neutral N 4 -donor N,N 0 -bis-pyridin-2-ylmethylene-hydrazine (pahn) and its derivatives [16][17][18][19][20][21][22][23][24][25]. On the other hand, helical complexes with the very similar N 2 O 2 -donor N,N 0 -bis-phenol-2-ylmethylene-hydrazine (H 2 salhn) were not known before we reported the neutral triple helical diiron(III) complex [Fe 2 (l-salhn) 3 ] [26].…”

“…In contrast, symmetric tetradentate diazine ligands (pahn and salhn 2À ) are well known to produce helical dinuclear complexes. In such symmetric ligands, when the two neutral chelating sites (pahn and related species) form five-membered chelate rings, cationic triple helical dinuclear complexes of larger bivalent metal ions are obtained [16][17][18][19][20][21][22][23][24][25]. On the other hand, if the chelating sites are monoanionic (salhn 2À and its derivatives) and can form six-membered chelate rings neutral dinuclear triple helical complexes of smaller trivalent metal ions are stabilised [26][27][28][29].…”