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The crystal structure of the title compound, C32H24O4, contains three fused di­hydro­pyran rings ( A, B and C); ring A is fused with a benzene ring while the other two rings, B and C, are fused with naphthalene rings. Ring A adopts a half-chair conformation with an equatorial methoxy group, whereas ring B assumes a distorted half-chair conformation, the A/ B ring junction being trans. Ring C adopts a distorted half-boat conformation and is nearly orthogonal to ring B. Ring C is inclined to the best plane of ring A at an angle of 112.1 (1)°. [ABSTRACT FROM AUTHOR]

Abstract: New nickel (II) complexes of 5-methyl-3-formylpyrazole-3-piperidinylthiosemicarbazone (HMP z 3Pi), [Ni(HMP z 3Pi)2]X2 ·2H2O (X=Cl, Br, ClO4, BF4 and NO3) have been synthesised and physico-chemically characterised by elemental analyses, magnetic susceptibility and conductivity measurements at RT, electronic and IR spectra. All the reported species are 1:2 electrolytic cationic complexes. Electronic spectra in the solid state and in MeOH solutions suggest a six-coordinate distorted octahedral geometry for all the reported complexes. IR spectral data (4000–200 cm−1) are indicative of a neutral NNS tridentate function of HMP z 3Pi coordinating to the central Ni(II) via the pyrazolyl (tertiary) ring nitrogen, azomethine nitrogen and thio-keto sulfur. X-ray crystallography of [Ni(HMP z 3Pi)2]Cl2 ·2H2O (, triclinic) has authenticated a NiN4S2 octahedral coordination and the pair of coordinating ligands (HMP z 3Pi) are almost orthogonal. A close scrutiny of the X-ray data of HMP z 3Pi (Pbca, orthorhombic) and [Ni(HMP z 3Pi)2]Cl2 ·2H2O (, triclinic) indicates an unusual rotation about the azomethine (C bond during complexation with Ni(II). A possible mechanism for such a rotation has been proposed. [Copyright &y& Elsevier]

The coordinating properties of the title ligand, 5-methyl-3-formyl pyrazole 3-hexamethyleneiminyl thiosemicarbazone (HMPz3Hex), synthesized and characterized (elemental analysis, MS, IR, 1H and 13C NMR and X-ray crystallography) for the first time, are reported by solid-state isolation of cobalt(III) complexes, [Co(MPz3Hex)2]X · nH2O (X=Cl, Br, NO3, ClO4 or BF4; n=1 to 2). The reported complex species have been spectroscopically characterized with X-ray structural identification of [Co(MPz3Hex)2]Br · H2O. IR and NMR data (1H and 13C) for the free ligand and its CoIII complexes confirm that the ligand, HMPz3Hex, behaves as a uninegative anion with NNS tridentate function via the pyrazolyl tert-nitrogen, azomethine nitrogen and thiol sulfur. Electronic spectral data recommend a distorted octahedral environment for the six-coordinate CoIII species. X-ray crystallography of [Co(MPz3Hex)2]Br · H2O (C2/c, monoclinic), has shown unambiguously that the crystallographic asymmetric unit consists of a [Co(MPz3Hex)2]+ cation and one Br− anion with one H2O molecule as solvent of crystallization. The two NNS ligands coordinate orthogonally to the central CoIII ion with mer-configuration. A critical scrutiny of the X-ray data of free HMPz3Hex (Pna21, orthorhombic) and [Co(MPz3Hex)2]Br · H2O indicates that an unusual rotation about the azomethine (C&z.dbnd6;N) double bond occurs during complexation with CoIII. A plausible reaction mechanism for the same has been proposed. Sulfur is involved in a C(7)–H(7)⋯S(1) intramolecular contact restricting the conformation of the ligand both in free and its complexed form. [Copyright &y& Elsevier]

New cobalt(III) and nickel(II) complexes of 5-methyl-3-formylpyrazole-N(4)-dibutylthiosemicarbazone (HMPzNBu2), [Co(MPzNBu2)2]X·H2O and [Ni(HMPzNBu2)2]X2 (X=Cl, Br, ClO4, BF4 and NO3), respectively, have been synthesised and physico-chemically characterised by magnetic measurements (polycrystalline state), 1H NMR [for Co(III) complexes], electronic and IR spectra. The reported species are all cationic complexes, behaving as 1:1 [for Co(III) complexes] and 1:2 [for Ni(II) complexes] electrolytes in MeOH. Electronic spectral features of the diamagnetic Co(III) and paramagnetic Ni(II) species classify them as six-coordinate distorted octahedral ones. IR spectra (4000–200 cm−1) indicate a monoprotic tridentate (NNS) function of HMPzNBu2 coordinating to the central Co(III) via the pyrazolyl (tertiary) ring nitrogen, azomethine nitrogen and thiolato sulfur atom; while for the Ni(II) complexes, HMPzNBu2 behaves as neutral NNS tridentate, bonding to Ni(II) through the pyrazolyl iminic nitrogen, azomethine nitrogen and thioketo sulfur. 1H NMR data (in DMSO-d6 at 300 MHz) for the uncomplexed ligand and those of its Co(III) complexes are commensurate with the propositions of bonding sites envisaged from IR data. X-ray crystallographic data of I (P1¯, triclinic) and of II (C2/c, monoclinic) have authenticated CoN4S2 and NiN4S2 octahedral coordination, respectively; in both I and II; the pair of coordinating ligands are nearly orthogonal to each other with the difference that while in I, the pair of ligands are monodeprotonated, in II, the same pair of ligands are neutral. [Copyright &y& Elsevier]

New iron(III) complexes of 5-methyl-3-formylpyrazole-3-piperidinylthiosemicarbazone (HMPz3Pi), [Fe(MPz3Pi)2]X·2H2O (X=Cl, ClO4 and NO3) have been synthesised and physico-chemically characterised by magnetic data (polycrystalline state), electronic, IR and EPR spectral studies. Each of the reported species is a cationic complex (1:1 electrolyte) containing two moles of monodeprotonated title ligand and an anionic counterpart. IR spectra (4000–200 cm−1) indicate coordination to the central iron(III) ion via the pyrazolyl (tertiary) ring nitrogen, azomethine nitrogen and thiolato sulfur atoms of the primary ligand molecule. EPR data (RT and LNT) show the presence of a low spin iron(III) cation with d2 xz d2 yz d1 xy configuration. X-ray crystallographic data of [Fe(MPz3Pi)2]ClO4·2H2O (P1¯, triclinic) have authenticated a FeN4S2 octahedral coordination as envisaged from spectral data. In the complex species, the two azomethine nitrogen atoms are trans to each other, while the pyrazolyl ring nitrogens and the thiolato sulfurs are in cis positions. [Copyright &y& Elsevier]

The co-ordination mode of the title ligand, HMPzNEt2 (synthesised for the first time and characterised by elemental analyses, mass, IR and 1H NMR spectral parameters), is reported by solid state isolation and physico-chemical identification of cobalt(III) complexes, [Co(MPzNEt2)2]X·2H2O (X=Cl, Br, ClO4, BF4 and NO3). Electronic spectral features of these diamagnetic Co(III) species classify them as six co-ordinate distorted octahedral ones. IR spectra (4000–200 cm−1) indicate that the Co(III) complexes have monoanionic tridentate NNS co-ordination of the title ligand through the pyrazolyl (tertiary) ring nitrogen, azomethine nitrogen and thiolato sulfur atoms. 1H NMR data (in CDCl3 at 300 MHz) for the uncomplexed ligand and those of its Co(III) complexes are commensurate with the NNS function of the monodeprotonated HMPzNEt2, as ascertained from downfield shift of the relevant protons adjacent to the bonding sites. X-ray crystallographic data of I and II (both P1¯, triclinic) have authenticated a CoN4S2 octahedral co-ordination in both the complex ions. [Copyright &y& Elsevier]

Abstract: A new azido derivative of a NNO donor tridentate Schiff-base copper(II) complex, [CuL(μ1,1-N3)] n (1) (HL=1-(N-ortho-hydroxyacetophenimine)-2-(N-ethyl)aminoethane), containing a single end-on μ1,1-azido bridged 1D infinite chain has been synthesized and characterized. X-ray single crystal structure analysis reveals that the complex [CuL(μ1,1-N3)] n (1) is a 1D chain in which neighboring Cu(II) chromophores are related by glide planes and linked by single azido bridges in the EO mode. No measurable magnetic interaction was evidenced in the complex [CuL(μ1,1-N3)] n (1) through variable temperature magnetic susceptibility measurements (10–300K). The complex was used as an active catalyst for the epoxidation of cyclooctene using tert-butyl-hydroperoxide as an oxidant. The catalytic activity of the complex has been compared in a series of solvents. The results show that in acetonitrile medium, the epoxide was produced in high yield with high selectivity. [Copyright &y& Elsevier]

Abstract: Two mixed-ligand copper(II) complexes [{Cu(L1)(μ1,3-N3)}{Cu(L)(μ1,3-N3)(μ1,1-N3)}] n (1) [HL1 =1-(N-ortho-hydroxyacetophenimino)-2,2-dimethyl-aminoethane; L=2-(dimethylamino)-ethylamine] and [{Cu(L2)(μ1,3-N3)}{Cu(L)(μ1,3-N3)(μ1,1-N3)}] n (2) [HL2 =1-(N-5-methoxy-ortho-hydroxyacetophenimino)-2,2-dimethyl-aminoethane] have been formed upon addition of aqueous solution of sodium azide to a methanolic solution of copper nitrate trihydrate and corresponding Schiff-base ligands. The ligands, HL1 and HL2 undergo partial hydrolysis of their imine bond during the course of reaction. Both the complexes contain single end-to-end (μ1,3) azido bridged 1D infinite chains (rail) which propagate parallel to the crystallographic b-axis; neighboring chains are interconnected by pairs through double asymmetric end-on (μ1,1) azido bridges (rung) to yield a ladder-like structure. In both complexes, rungs (end-on azido bridges) do not connect copper centers of the chains like in a regular ladder; instead they connect only the alternating copper sites of the 1D chain. In a chain the coordination environment around copper(II) ions are not the same: while the {Cu(L1)(μ1,3-N3)} and {Cu(L2)(μ1,3-N3)} moieties have a penta-coordinated copper(II) center, the copper(II) ion of the neighboring {Cu(L1)(μ1,3-N3)(μ1,1-N3)} or {Cu(L2)(μ1,3-N3)(μ1,1-N3)} moiety has an octahedral coordination environment. The variable temperature (2–300K) magnetic susceptibility measurements showed that the magnetic interaction between the metal centers in complexes 1 and 2 is dominantly antiferromagnetic. The results of magnetic model are in good agreement with the experimental data. [Copyright &y& Elsevier]

Abstract: A new azido derivative of tridentate Schiff base copper(II) complex has been synthesized and characterized. X-ray single crystal structure analysis reveals that the complex [Cu2L2(N3)2(NO3)2] (1), containing 1-(N-pyridylimino)-3-aminopropane (L) as co-ligand, is a dimer in which copper(II) ions are bridged by two azido groups in end-on fashion. The coordination environment around copper(II) is distorted octahedral which is rarely observed among these types of azido bridged copper(II) dimers. Three among the four coordination sites of the basal plane of the octahedron are occupied by the nitrogen atoms of the Schiff base and the fourth site is occupied by a nitrogen atom of a μ2-1,1 bridging azido ligand. While one of the apical coordination is provided by a nitrogen atom of an end-on bridging azido ion from a symmetry related [CuL(N3)(NO3)] unit to give rise the dinuclear moiety, [Cu2L2(N3)2(NO3)2], the remaining site of the octahedron is occupied by an oxygen atom of the coordinated ion. The variable temperature magnetic susceptibility measurements evidenced an antiferromagnetic interactions, in [Cu2L2(N3)2(NO3)2] (1). [Copyright &y& Elsevier]

Abstract: A new rare variety asymmetric μ2-1,1-azido bridged copper(II) complex has been synthesized and characterized structurally and magnetically. The complex [Cu2L2(μ2-1,1-N3)2]·H2O·CH3OH (L =1-(N-ortho-hydroxyacetophenimine)-2-aminoethane) (1), crystallizes in monoclinic space group, P21/n, with a =9.469(4)Å, b =12.526(8)Å, c =12.899(10)Å, β =105.79(6)°, V =1472.2(16)Å3. X-ray study reveals that he Cu–N(azide)–Cu angles in this complex is 90.4°. This is unusually low in comparison to that of the same angle in other end-on azido-bridged binuclear complexes. Though a strong ferromagnetic interaction between the metal centers is expected in the complex, the coupling has actually been found to be antiferromagnetic (J =−4.2cm−1), instead. To rationalize this paradoxical magnetic behavior, DFT calculation of this and other four complexes with very similar structure have been performed within broken symmetry framework. The calculated magnetic coupling constants (J) are in excellent agreement, both in sign and in the magnitude of the exchange interaction, with the experimental data, and the spin density map is correctly reproduced. [Copyright &y& Elsevier]

[Display omitted] • The structure is binuclear unit of Cu linked through two thiocyanate. • The coordination geometry encompassing each of metal is a square pyramidal. • The 1D and 2D chain of Cu dinuclear unit is extended by Hydrogen bonds. • The magnetic susceptibility data show ferromagnetic coupling. A new Cu (II)-dinuclear, [Cu 2 -(µ-NCS) 2 (NCS) 2 (Nicotinamide) 4 ] complex was synthesized, and its single crystal X-ray structure was determined. The complex was further characterized by IR spectra, TGA and EPR spectroscopy and its magnetic behaviour was studied in detail. The complex consists of a binuclear unit in which two copper atoms are connected through two thiocyanate end to end (equatorial N-axial S) bridges. The coordination geometry around each of the metal centre in the dinuclear is square pyramidal, where basal plane is occupied by two nitrogen atoms from two nicotinamide moieties (Pyridine ring-N), one nitrogen atom from bridging thiocyanate and one nitrogen of non-bridging thiocyanate anion. The axial positions in the square pyramid of each copper centre of the dinuclear is occupied by sulphur atom of the two bridging thiocyanate moieties which are equatorially bonded to neighbouring copper atom of same dinuclear unit through nitrogen end. The dinuclear chain is extended by hydrogen bonding resulting into a 1D and 2D structure. The temperature dependent magnetic susceptibility of compound was carried out at 1000 Oe in the temperature range of 2–300 K. This behaviour indicates that the intra dinuclear magnetic interactions between the paramagnetic Cu(II) atoms is of ferromagnetic nature. [ABSTRACT FROM AUTHOR]

Humans routinely sit or lean against supporting surfaces and it is important to shape these surfaces to be comfortable and ergonomic. We give a method to design the geometric shape of rigid supporting surfaces to maximize the ergonomics of physically based contact between the surface and a deformable human. We model the soft deformable human using a layer of FEM deformable tissue surrounding a rigid core, with measured realistic elastic material properties, and large-deformation nonlinear analysis. We define a novel cost function to measure the ergonomics of contact between the human and the supporting surface. We give a stable and computationally efficient contact model that is differentiable with respect to the supporting surface shape. This makes it possible to optimize our ergonomic cost function using gradient-based optimizers. Our optimizer produces supporting surfaces superior to prior work on ergonomic shape design. Our examples include furniture, apparel and tools. We also validate our results by scanning a real human subject's foot and optimizing a shoe sole shape to maximize foot contact ergonomics. We 3D-print the optimized shoe sole, measure contact pressure using pressure sensors, and demonstrate that the real unoptimized and optimized pressure distributions qualitatively match those predicted by our simulation.

In the title compound, [Co(NCS)2(C6H6N2O)2(H2O)2], the Co(II) cation is located on an inversion centre and is coordinated by two thio-cyanate anions, two nicotinamide mol-ecules and two water mol-ecules in a distorted N2O2S2 octa-hedral geometry. The amide group is twisted by 31.30 (16)° with respect to the pyridine ring. In the crystal, mol-ecules are linked by O-H⋯O, O-H⋯S and N-H⋯S hydrogen bonds into a three-dimensional supra-molecular network. Weak π-π stacking is observed between parallel pyridine rings of adjacent mol-ecules, the centroid-centroid distance being 3.8270 (19) Å.