Kateryna O. Znovjyak

N-[Bis(dimethyl­amino)phosphinoyl]-2,2,2-trichloro­acetamide

In the title compound, C6H13Cl3N3O2P or CCl3C(O)NHP(O)(N(CH3)2), the phosphinoyl group is synclinal to the carbonyl group and acts as an acceptor for an intermolecular N—H⋯O hydrogen bond from the amide group as the donor.

Bis{N-[bis­(pyrrolidin-1-yl)phosphor­yl]-2,2,2-trichloro­acetamide}di­nitrato­dioxidouranium(VI)

The crystal structure of the title compound, [U(NO3)2O2(C10H17Cl3N3O2P)2], is composed of centrosymmetric [UO2(L)2(NO3)2] molecules {L is N-[bis(pyrrolidin-1-yl)phosphoryl]-2,2,2-trichloroacetamide, C10H17Cl3N3O2P}. The UVI ion, located on an inversion center, is eight-coordinated with axial oxido ligands and six equatorial oxygen atoms of the phosphoryl and nitrate groups in a slightly distorted hexagonal-bipyramidal geometry. One of the pyrrolidine fragments in the ligand is disordered over two conformation (occupancy ratio 0.58:0.42). Intramolecular N—H⋯O hydrogen bonds between the amine and nitrate groups are found.

catena-Poly[[[aqua­copper(II)]-bis­[μ-bis­(3,5-dimethyl-1H-pyrazol-4-yl) selenide-κ2N2:N2′]] dichloride monohydrate]

In the title compound, {[Cu(C10H14N4Se)2(H2O)]Cl2·H2O}n, the CuII ion, lying on a twofold rotation axis, has a square-pyramidal geometry constituted by four N atoms of pyrazolyl groups in the basal plane and an apical O atom of a water molecule. A pair of bis(3,5-dimethyl-1H-pyrazol-4-yl) selenide ligands bridge the Cu centers into a polymeric double-chain extending along [001]. The chloride anions are involved in intermolecular N—H⋯Cl and O—H⋯Cl hydrogen bonds, which link the chains into a three-dimensional network.

Imparting hysteretic behavior to spin transition in neutral mononuclear complexes

A series of spin transition neutral compounds [FeL(NCS)2] has been synthesized and characterized by means of magnetic susceptibility studies, X-ray diffraction, IR and Mossbauer spectroscopic, and calorimetric measurements (L = N,N-bis((3-alkoxypyridin-2-yl)methylene)-propane-1,3-diamine, number of carbon atoms in chains (n) = 4, 12, 14, 16, 18, 20). The shortest chain compound is crystalline and displays a gradual spin transition above ambient temperature. Growing the aliphatic substituent up to n = 12 and 14 leads to loss of crystalline order and deterioration of magnetic properties. At the critical chain length n = 16 and above, the compounds undergo a phase transition reflected by a spin transition and resulting in the appearance of susceptibility hysteresis initially not observed for the short chain congener. For the compound with n = 20, hysteresis becomes the most pronounced. The study shows the importance of chain length optimization for effective feedback between phase and spin transitions.

4-Chloro­selanyl-3,5-diethyl-1H-pyrazol-2-ium chloride

In the cation of the title compound, C7H12ClN2Se+·Cl−, the ethylene groups and the Se–Cl fragment adopt a cis configuration with a C—Se—Cl angle of 96.09 (6)°. In the crystal, intermolecular N—H⋯Cl hydrogen bonds link two cations and two chlorine anions into centrosymmetric clusters. π–π interactions between the pyrazole rings [centroid–centroid distance of 3.530 (2) Å] link these clusters into columns along [001] with short intermolecular Se⋯Cl− contacts of 2.995 (1) Å.

catena-Poly[[[aqua­copper(II)]bis­[μ-bis(3,5-dimethyl-1H-pyrazol-4-yl) selenide]] bis­(tetra­fluorido­borate) bis­(triphenyl­phosphine oxide) monohydrate]

The title compound, {[Cu(C10H14N4Se)2(H2O)](BF4)2·2C18H15PO·H2O}n, has a polymeric structure where each CuII ion adopts a square-pyramidal coordination constituted by four N atoms of pyrazole moieties in the equatorial plane and an axial O atom of a water molecule. A pair of bis(3,5-dimethyl-1H-pyrazol-4-yl) selenide ligands bridges the CuII centres into a chain extending along the c axis. The water molecules, anions and triphenylphosphine oxide molecules are involved in intermolecular hydrogen bonding, which links the chains into a three-dimensional network.

{Dimeth­yl [(phenyl­sulfon­yl)amido­]phosphato-κ2O,O′}bis­(tri­phenylphosphane-κP)copper(I)

In the title complex, [Cu(C8H11NO5PS)(C18H15P)2], the CuI ion is coordinated by two triphenylphosphane molecules and two O atoms of the chelating dimethyl(phenylsulfonyl)amidophosphate anion, generating a squashed CuO2P2 tetrahedron. In the six-membered chelate ring, the Cu, P and O atoms are almost coplanar (r.m.s. deviation = 0.024 Å), with the N and S atoms displaced in the same direction, by 0.708 (5) and 0.429 (2) Å, respectively.

[Di­aqua­sesqui(nitrato-κO)hemi(perchlorato-κO)copper(II)]-μ-{bis­[5-methyl-3-(pyridin-2-yl)-1H-pyrazol-4-yl] selenide}-[tri­aqua­(perchlorato-κO)copper(II)] nitrate monohydrate

In the binuclear title complex, [Cu2(ClO4)1.5(NO3)1.5(C18H16N6Se)(H2O)5]NO3·H2O, both CuII ions are hexacoordinated by O and N atoms, thus forming axially elongated CuO4N2 octahedra. The equatorial plane of each octahedron is formed by one chelating pyrazole–pyridine fragment of the organic ligand and two water molecules. The axial positions in one octahedron are occupied by a water molecule and a monodentately coordinated perchlorate anion, while those in the other are occupied by a nitrate anion and a disordered perchlorate/nitrate anion with equal site occupancy. The pyrazole–pyridine units of the organic selenide are trans-oriented to each other with a C—Se—C angle of 96.01 (14)°. In the crystal, uncoordinated nitrate anions and the coordinating water molecules are involved in O—H⋯O and N—H⋯O hydrogen bonds, forming a bridge between the pyrazole group and the coordinating water molecules. Further O—H⋯O hydrogen bonds between the complex molecules and a π–π stacking interaction with a centroid–centroid distance of 3.834 (4) Å are also observed.

Bis{4-[(3,5-dimethyl-1H-pyrazol-4-yl)selan­yl]-3,5-dimethyl-1H-pyrazol-2-ium} chloride monohydrate

In the title compound, 2C10H15N4Se+·Cl−·OH−, a singly protonated molecule of the organic selenide participates in hydrogen bonding with neighboring molecules, forming zigzag chains along [001]. The molecule adapts a cis bridging mode with a C—Se—C angle of 102.13 (15)°. π–π stacking interactions are observed between the closest pyrazole rings of neighboring chains [centroid–centroid distance = 3.888 (1) Å] and hydrogen bonding occurs through bridging chloride anions and hydroxide groups. Additionally, O—H⋯Cl hydrogen bonds are formed.

Bis{2-hydroxy­imino-N′-[1-(2-pyrid­yl)ethyl­idene]propanohydrazidato}zinc(II) dihydrate

The title compound, [Zn(C10H11N4O2)2]·2H2O, was prepared by the reaction between Zn(CH3COO)2·2H2O and 2-hydroxyimino-N′-[1-(2-pyridyl)ethylidene]propanohydrazide (Hpop). The central ZnII atom has a distorted tetragonal-bipyramidal coordination geometry formed by two amide O atoms and four N atoms of two azomethine and two pyridine groups. In the crystal, complex molecules form layers parallel to the crystallographic b direction. The layers are connected by O—H⋯N and O—H⋯O hydrogen bonds involving the solvent water molecules.