Crystal structure of 1-meth-oxy-2,2,2-tris-(pyrazol-1-yl)ethane.

The title compound, C12H14N6O, consists of three pyrazole rings bound via nitro-gen to the distal ethane carbon of meth-oxy ethane. The dihedral angles between the three pyrazole rings are 67.62 (14), 73.74 (14), and 78.92 (12)°. In the crystal, mol-ecules are linked by bifurcated C-H,H⋯N hydrogen bonds, forming double-stranded chains along [001]. The chains are linked via C-H⋯O hydrogen bonds, forming a three-dimensional framework structure. The crystal was refined as a perfect (0.5:0.5) inversion twin.

Bis[1-meth-oxy-2,2,2-tris-(pyrazol-1-yl-κN (2))ethane]-nickel(II) bis-(tri-fluoro-methane-sulfonate) dihydrate.

In the title salt, [Ni(C12H14N6O)2](CF3SO3)2·2H2O, the Ni(II) cation is located on an inversion centre and is coordinated by six N atoms from two tridentate 1-meth-oxy-2,2,2-tris-(pyrazol-1-yl)ethane ligands in a distorted octa-hedral geometry. The Ni-N distances range from 2.0594 (12) to 2.0664 (12) Å, intra-ligand N-Ni-N angles range from 84.59 (5) to 86.06 (5)°, and adjacent inter-ligand N-Ni-N angles range between 93.94 (5) and 95.41 (5)°. In the crystal, inversion-related pyrazole rings are π-π stacked, with an inter-planar spacing of 3.4494 (18) Å, forming chains that propagate parallel to the a-axis direction. Inter-molecular O-H⋯O hydrogen bonds are present between water mol-ecules and tri-fluoro-methane-sulfonate anions.

Bis[1-meth-oxy-2,2,2-tris-(pyrazol-1-yl-κN (2))ethane]-nickel(II) bis-(tri-fluoro-methane-sulfonate) methanol disolvate.

In the title salt, [Ni(C12H14N6O)2](CF3SO3)2·2CH3OH, the Ni(II) ion is coordinated by six N atoms from two tridentate 1-meth-oxy-2,2,2-tris-(pyrazol-1-yl)ethane ligands in a distorted octa-hedral geometry. The Ni(II) ion is situated on an inversion centre. The Ni-N distances range from 2.0589 (19) to 2.0757 (19) Å, intra-ligand N-Ni-N angles range from 84.50 (8) to 85.15 (8)°, and adjacent inter-ligand N-Ni-N angles range between 94.85 (8) and 95.50 (8)°. In the crystal, O-H⋯O hydrogen bonds between methanol solvent mol-ecules and tri-fluoro-methane-sulfonate anions are observed.

Bis[tris-(3,5-dimethyl-1H-pyrazol-1-yl-κN(2))meth-yl]sodium trifluoro-methane-sulfonate.

In the title salt, [Na(C(16)H(22)N(6))(2)]CF(3)SO(3), the Na(+) cation is coordinated by six N atoms from two tridentate tris-(3,5-dimethyl-pyrazol-1-yl)methane ligands in a distorted octa-hedral geometry. The Na-N distances range from 2.427 (3) to 2.507 (3) Å, intra-ligand N-Na-N angles range from 74.71 (8) to 79.31 (9)°, and adjacent inter-ligand N-Na-N angles range between 100.42 (9) and 104.97 (9)°. The structure is twinned by inversion [occupancy factors = 0.50 (9)] and the trifluoro-methane-sulfonate anion is disordered, with two end-over-end orientations of unequal occupancy [0.781 (3) and 0.219 (3)].

Tetra-ethyl-ammonium tris-(thio-cyanato-κN)[tris-(1H-pyrazol-1-yl-κN(2))methane]-nickelate(II).

The title salt, (C8H20N)[Ni(NCS)3(C10H10N6)], consists of a tetra-ethyl-ammonium cation and an anion comprising an octa-hedral Ni(II) atom surrounded by three N atoms from a tripodal tris-(pyrazol-1-yl)methane ligand, and three thio-cyanate ligands, each bound at the N-atom end. The ligand Ni-N distances range from 2.097 (2) to 2.127 (2) Šfor the tripodal ligand and from 2.045 (2) to 2.075 (2) Šfor the thio-cyanate ligands. The dihedral angles between the three pyrazole rings are 59.03 (12), 53.09 (10) and 67.90 (10)°.

Synthesis and characterization of di- and trivalent pyrazolylborate ß-diketonates and cyanometalates.

The syntheses, structures, and magnetic properties of a series of di- and trivalent hydridotris(3,5-dimethylpyrazol-1-yl)borate (Tp*) cyanomanganates are described. Treatment of tris(acetylacetonate)manganese(III) [Mn(acac)(3)] with KTp* and tetra(ethyl)ammonium cyanide affords [NEt(4)][(Tp*)Mn(II)(κ(2)-acac)(CN)] (1), as the first monocyanomanganate(II) complex; attempted oxidation of 1 with iodine affords {(Tp*)Mn(II)(κ(2)-acac(3-CN))}(n) (2) as a one-dimensional chain and bimetallic {[NEt(4)][(Tp*)Mn(II)(κ(2)-acac(3-CN))](2)(µ-CN) (3) as the major and minor products, respectively. A fourth complex, [NEt(4)][(Tp*)Mn(II)(η(2)-acac(3-CN))(η(1)-NC-acac)] (4), is obtained via treatment of Mn(acac(3-CN))(3) with KTp* and [NEt(4)]CN, while [NEt(4)](2)[Mn(II)(CN)(4)] (5) was prepared from manganese(II) trifluoromethanesulfonate and excess [NEt(4)]CN. Tricyanomanganate(III) complexes, [cat][(Tp*)Mn(III)(CN)(3)] [cat = NEt(4)(+), 7; PPN(+), 8], are prepared via sequential treatment of Mn(acac(3-CN))(3) with KTp*, followed by [NEt(4)]CN, or [cat](3)[Mn(III)(CN)(6)] with (Tp*)SnBu(2)Cl. Magnetic measurements indicate that 1, 2, and 4 contain isotropic Mn(II) (S = (5)/(2); g = 2.00) centers, and no long-range magnetic ordering is found above 1.8 K. Compounds 7 and 8 contain S = 1 Mn(III) centers that adopt singly degenerate spin ground states without orbital contributions to their magnetic moments.

Bis[tris-(1H-pyrazol-1-yl-κN)methane]-nickel(II) bis-{[tris-(1H-pyrazol-1-yl-κN)methane]-tris-(thio-cyanato-κN)nickelate(II)} methanol disolvate.

Attempts to prepare the mononuclear [(tpm)Ni(II)L(3)](-1) [tpm = tris-(1H-pyrazol-1-yl)methane and L = thio-cyanate] anion yielded the methanol-solvated salt, [(tpm)(2)Ni(II)][(tpm)Ni(II)(NCS)(3)](2)·2CH(3)OH or [Ni(C(10)H(10)N(6))(2)][Ni(NCS)(3)(C(10)H(10)N(6))](2)·2CH(3)OH. The asymmetric unit consists of half a centrosymmetric bis-[tris-(1H-pyrazol-1-yl)methane]-nickel(II) cation and an octa-hedral nickelate(II) anion bound to one tpm and three L ligands, and a methanol solvent mol-ecule. One of the L ligands is disordered over two positions with occupancy factors of 0.650 (3) and 0.350 (3). There are O-H⋯S inter-actions between the methanol and the disordered thio-cyanate anion, and a weak C-H⋯O hydrogen bond between the cation and the methanol O atom.

First structurally characterized tricyanomanganate(III) and its magnetic {Mn(III)(2)M(II)(2)} complexes (M(II) = Mn, Ni).

Treatment of tris(3-cyano-2,4-pentanedionato)manganese(III) with KTp*, followed by [NEt(4)]CN affords [NEt(4)][(Tp*)Mn(III)(CN)(3)] (1); subsequent treatment of 1 with divalent triflates (OTf) and 2,2'-bipyridine (bpy) affords {Mn(III)(2)M(II)(2)} complexes (M(II) = Mn, 2; Ni, 3). Magnetic measurements show that 1-3 exhibit S(T) = 1, 3, and 4 spin ground states, respectively.

A cyano-based octanuclear {Fe(III)(4)Ni(II)(4)} single-molecule magnet.

A new low symmetry octanuclear cyano-based {Fe(III)(4)Ni(II)(4)} single-molecule magnet (SMM) is described. This SMM exhibits the highest energy barrier (Delta/k(B) approximately 33 K) for magnetization reversal seen for any first-row cyanide-based complex. The importance of anisotropy axes alignment and their impact on SMM properties are illustrated when cubic {Fe(III)(4)Ni(II)(4)} boxes are compared to octanuclear complexes of lower overall symmetry.