Synthesis and Crystal Structure of Trans-diaquabis(hexamethylenetetramine-N)bis(isothiocyanato)cobalt(Ⅱ) trans-tetraaquabis(isothiocyanato)cobalt(Ⅱ) dihydrate

1 INTRODUCTION Supramolecular compounds assembled by coordination covalent bonding or hydrogen bonding are of considerable interest due to their potential applications in developing new materials with magnetic, optical and catalytic properties[1]. One of the synthesis methods used to construct the functional compounds is that octahedral metal ion connects to polydentate ligand such as 4, 4?bipyridine, pyrazine and so on to form multi-dimensional supramolecular polymer[2]. Hmt (hexamethyl…     

Studies in werner clathrates. Part 2. Structures of bis (isothiocyanato) tetra (4-phenylpyridine) nickel (II)· 4-dimethylsulphoxide,bis (isothiocyanato) tetra (3-methylpyridine) nickel (II)· chloroform and bis (isothiocyanato) tetra (3,5-dimethylpyridine) nickel (II)

The structures of Ni(NCS)₂(4-PhPy)₄·4DMSO and Ni(NCS)₂(3-MePy)₄·CHCl₃ have been elucidated. Movement of guest molecules through channels in the host structure was simulated by potential energy calculations. Ni(NCS)₂(3,5-diMePy)₄ does not form inclusion compounds. An intra-molecular potential energy study shows that theortho-hydrogens on the 3,5-dimethylpyridine ligands control the conformation of the molecule. The same result is obtained with the 4-methylpyridine ligand, which suggests that the extent of rotation of substituted pyridines about the Ni–N bounds is not a factor governing clathrate formation. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82030 (43 pages).     

Synthesis and structure of dimeric bis(isothiocyanato)tris (4-methylpyridine)nickel (II)

Summary The Ni₂(NCS)₄(4-Methylpyridine)6 complex has been prepared crystalline from methanolic solutions of Ni(NCS)2(4-Methylpyridine)4. Three dimensional x-ray diffraction data were collected by means of an automated single crystal diffractometer. The structure was solved by Patterson methods and refined to a final R value of 0.075, based on 2422 observed_ reflections. The compound crystallizes in space group P1 with one dimeric molecule in a unit cell of dimensions a = 10.57(1), 6 = 14.06(1), c = 8.66(1) Å, = 105.2(1), = 114.8(1), y = 95.6(1)°. The Ni atoms have distorted octahedral coordination with one sulfur and five nitrogen atoms - two of the four thiocyanate groups form a double bridge between the neighbouring Ni atoms.4-MePy = 4-Methylpyridine     

Crystal structure of bis(isothiocyanato)diaquabis(pyridine)-magnesium(II) solvate with pyridine 1:4

Abstract

Single crystal X-ray structure of solvate of [MgPy₂(H₂O)₂(NCS)₂](Py = Pyridine) complex with pyridine 1:4 at -50 °C is reported. It is monoclinc P2₁/n, with: a = 9.530(5), b = 12.495(4), c = 15.592(5) Å, β = 90.11(4)°, D_calc. = 1.165 g·cm^?3, Z = 2. The number of data are 4215 (measured) and 1251 (unique-observed). The final R values are R = 0.082 (unit weights) and R_w = 0.067. In the centrosymmetric complex molecule the Mg(II) cation is octahedrally coordinated by four N and two O of the three pairs of trans-arranged ligands. Four solvating pyridine molecules form a second coordination sphere, with two pyridines connecting to each water ligand by means of hydrogen bonds.     

Two clathrates of bis(isothiocyanato)tetrakis(4-methylpyridine)magnesium(II) as a host with 4-methylpyridine as a guest

Two clathrate modifications of the title host with 4-methylpyridine (4-CH₃C₅H₄N) as a guest have been determined at –50°C. [Mg(4-CH₃C₅H₄N)₄(NCS)₂] · 2/3(4-CH₃C₅H₄N) · 1/3H₂O is trigonal, space group , witha=27.630(7),c=11.219(3) ÅV=7417(4) ų,Z=9,D _calc=1.171 g cm^–3,(CuK )=18.506 cm^–1, finalR=0.064. [Mg(4-CH₃C₅H₄N)₄(NCS)₂] · (4-CH₃C₅H₄N) is tetragonal, space group I4_l/a, witha=16.944(7),c=23.552(9)Å,V=6762(5) Å,Z=8,D _calc=1.191 g cm^–3, (CuK )=18.200 cm^–1, finalR=0.071.The structures consist of molecular packings of the same host complex units and the guest species. The Mg(II) cation is octahedrally coordinated to theN-atoms of four 4-methylpyridine and twotrans-coordinated isothiocyanato ligands in the host molecule. The conformations of the molecule are considerably different both in symmetry and in geometry in these two structures. The guest 4-methylpyridine molecules are disordered into channels which have different topology in these two clathrates resulting in different thermal stability.     

Hexa­aqua­cobalt(II) bis(4‐toluene­sulfonate)

The title compound, [Co(H₂O)₆](CH₃C₆H₄SO₃)₂, has a structure where the metal atom is surrounded by six mol­ecules of water forming the cation and the anion is deprotonated 4‐toluene­sulfonic acid. The Co atom is in a nearly regular octahedral coordination geometry, with Co—O distances between 2.0529 (14) and 2.0810 (16) Å, and angles ranging from 87.25 (9) to 92.75 (9)°. The supramolecular structure consists of parallel layers of cations and anions. The anions are arranged with their sulfonate groups directed towards the cation layer in an alternating fashion and form hydrogen bonds with the water mol­ecules of the cation.     

High-frequency and -field EPR of a pseudo-octahedral complex of high-spin Fe(II): bis(2,2'-bi-2-thiazoline)bis(isothiocyanato)iron(II)

A pseudo-octahedral complex of high-spin Fe(II), bis(2,2'-bi-2-thiazoline)bis(isothiocyanato)iron(II), which has a cis-FeN'2N4 chromophore, has been investigated by high-frequency, high-field electron paramagnetic resonance (HFEPR). Complementary M?ssbauer and DC magnetic susceptibility studies were also performed. HFEPR spectra of powder samples were recorded at frequencies up to 700 GHz and over a magnetic field range of 0-25 T. Analysis of the field-frequency data set yields the following set of spin Hamiltonian parameters for S = 2: D = +12.427(12) cm-1, E = +0.243(3) cm-1; gx = 2.147(3), gy = 2.166(3), gz = 2.01(1). The parameters are analyzed by use of a simple crystal-field model. This study represents the first precise determination by HFEPR of spin Hamiltonian parameters in six-coordinate high-spin Fe(II) and indicates the applicability of HFEPR to the study of high-spin Fe(II) in coordination complexes and biological model compounds.     

Clathrate inclusiom compounds of bis(isothiocyanato) tetrakis (4-methylpyridine) nickel II: II. Arrangement of guest molecules in the β-Ni(NCS)2(4-methylpyrldine)4 porous crystals

In this paper crystal structures of three tetragonal 14₁/a β-Ni(NCS)₂(4-Methylpyridine)₄ clathrates containing p-xylene (1:1), m-xylene (1:1) and methanol (2:1 mole of guest/mole of host), respectively, as the guest components are reported and discussed.The guest molecules were found to occupy centrosymmetric cavities in the hoat structure. Non-centrosymmetric m-xylene molecules are disordered to at least two orientations interrelated by inversion; methanol molecules enter the cavities as centrosymmetric pairs.