Mixed‐Valence Nickel Bis(azamacrocycle) Compounds with Ghost‐Leg‐type Sheets

Abstract

The fabrication of so-called ghost-leg sheets and their electronic properties is reported. This unique sheet structure is composed of one-dimensional mixed-valence nickel chains, which are linked with one another by bis(azamacrocycle) ligands. They are also topologically unique Ni /Ni mixed-valence complexes, as confirmed by X-ray and optical measurements. Moreover, their magnetic susceptibilities indicated two-dimensional antiferromagnetic behavior following the Fisher 1D chain model with interchain interactions, where spins on Ni sites mutually interact antiferromagnetically in the sheets.

Multiple-Hydrogen-Bond Approach to Uncommon Pd(III) Oxidation State: A Pd–Br Chain with High Conductivity and Thermal Stability

“…These drawbacks must be overcome to produce desired intrinsic physical properties, such as high conductivities and gigantic third-order nonlinearities, possibly greater than those reported for isomorphic Ni­(III)Br chains . Moreover, since Pd­(III) ions are substitutionally inert, Pd­(III)-based properties can be introduced into various supramolecular architectures, such as soluble nanowires, single-crystalline ladder systems , and nanotubes, , which is difficult in the case of labile Ni ions. Herein, we report a new approach for stabilizing a Pd­(III) AV state.…”

Coordination Polymers of the Macrocyclic Nickel(II) and Copper(II) Complexes with Isomeric Benzenedicarboxylates: The Case of Spatial Complementarity between the Bis-Macrocyclic Complexes and o-Phthalate

“…So, simultaneously changing the angle C3–N3–C6–C6 ii in both macrocyclic subunits by the same value results in a set of centrosymmetrically stretched conformations of L en that differ by Cu···Cu distances (8.4–10.0 Å) and the distances between the parallel CuN 4 mean planes (0.6–2.4 Å) (Table S6). These parameters for the bis-macrocyclic ligand in 9 are, correspondingly, the largest (9.940(2) Å) and the smallest (0.730(6) Å) among all complexes of L en characterized experimentally so far ,, (see Table S5). This is explained by the specific combination of torsion angles and the highest degree of flattening of the distal N3 atom.…”

“…Structural features of the copper­(II) and nickel­(II) complexes based on the bis-macrocyclic core L en described in the literature are similar to those observed in 9 . They include the perchlorate salt of the dicopper­(II) cation ( FIGSEU ), mixed-valent dinickel­(II)/(III) 2D CPs with chloride and bromide bridging anions ( HARTOM and HARTUS ), as well as 3D CP formed by the dinickel­(II) cation and 1,1′-biphenyl-3,3′,5,5′-tetracarboxylate ( TUDMAH ) . The bis-macrocyclic ligand in these complexes is strictly (or approximately, as in HARTUS ) centrosymmetric with an inversion center lying in the middle of the C–C bond of the linker and the ligand as a whole adopts a stretched conformation with maximally remote macrocyclic subunits (Table S5).…”

“…Additionally, several polymeric compounds based on such SBUs have been characterized, and these can be divided into two groups. The first group represents two-dimensional (2D) CPs formed by mixed-valent nickel­(II)/(III) complexes of L en with chloride and bromide anions . The second group consists of three-dimensional (3D) carboxylate polymers built up of [Ni 2 (L en )] 4+ and [Ni 2 (L bn )] 4+ cations and 1,1′-biphenyl-3,3′,5,5′-tetracarboxylate, and 2D polymers based on [Ni 2 (L pxyl )] 4+ and 1,3,5-benzenetricarboxylate, , as well as CPs based on [Cu 2 (L pxyl )] 4+ and terephthalate .…”

“…The first group represents two-dimensional (2D) CPs formed by mixed-valent nickel(II)/(III) complexes of L en with chloride and bromide anions. 26 The second group consists of three-dimensional (3D) carboxylate polymers built up of [Ni 2 (L en )] 4+ and [Ni 2 (L bn )] 4+ cations and 1,1′-biphenyl-3,3′,5,5′-tetracarboxylate, 27 and 2D polymers based on [Ni 2 (L pxyl )] 4+ and 1,3,5-benzenetricarboxylate, 25,28 as well as CPs based on [Cu 2 (L pxyl )] 4+ and terephthalate. 29 In all previously mentioned CPs, the bis-macrocyclic ligands adopt a stretched conformation with maximally distant macrocyclic subunits, and each carboxylate bridge links the metal ions belonging to different bis-macrocyclic molecules (intermolecular coordination).…”