μ‐Oxo‐bis{[(6‐hydroxy­methyl‐2‐pyridyl­methyl)­bis(2‐pyridyl­methyl)­amine‐κ5N,N′,N′′,N′′′,O]­iron(III)} tetrakis­(perchlorate)

The novel μ‐oxo‐diiron complex [Fe₂O(BPHPA)₂](ClO₄)₄ [BPHPA is (6‐hydroxy­methyl‐2‐pyridyl­methyl)­bis(2‐pyridyl­methyl)­amine, C₁₉H₂₀N₄O], contains a binuclear centrosymmetric [Fe₂O(BPHPA)₂]⁴⁺ cation (the bridging O atom lies on an inversion centre) and four perchlorate anions. Each iron ion is coordinated by four N atoms [Fe—N = 2.117 (5)–2.196 (5) Å] and one O atom [Fe—O = 2.052 (5) Å] from a BPHPA ligand, and by one bridging oxo atom [Fe—O = 1.7896 (9) Å], forming a distorted octahedron. There are hydrogen bonds between the hydroxy group and perchlorate O atoms [O—H·O = 2.654 (7) Å].     

μ‐Chloro‐bis{[benzylbis(2‐pyridyl­methyl)­amine‐κ3N]­chloro­copper(II)} perchlorate hemi­hydrate

In the title dinuclear Cu^II compound, [Cu₂Cl₃(C₁₉H₁₉N₃)₃]ClO₄·0.5H₂O, the coordination geometry around the Cu atoms is square pyramidal, with the bridging Cl atom at the apical positions. The Cu—Cl—Cu angle is 136.9 (1)° and the Cu?Cu distance is 4.961 (1) Å.     

Bis[bis(methoxycarbimido)aminato]copper(II) 1‐methylpyrrolidin‐2‐one disolvate

The title compound, [Cu(C₄H₈N₃O₂)₂]·2C₅H₉NO, consists of a neutral copper complex, in which the Cu^II centre coordinates to two bis(methoxycarbimido)aminate ligands, solvated by two molecules of 1‐methylpyrrolidin‐2‐one. The complex is planar and centrosymmetric, with the Cu^II centre occupying a crystallographic inversion centre and adopting approximately square‐planar geometry. N—H...O hydrogen‐bonding interactions exist between the amine NH groups of the ligands and the O atoms of the 1‐methylpyrrolidin‐2‐one molecules. The associated units pack to form sheets.     

Ethyl (2‐pyridyl­methyl)­phospho­nate

Molecules of the title compound, C₈H₁₂NO₃P, exist as zwitterions. The positive charge formally located on the N atom is spread over the pyridyl ring. A partial delocalization of negative charge within the O—P—O system is observed. The conformational features and hydrogen‐bonding network of the title compound are compared with the structure of (2‐pyridyl­methyl)­phosphonic acid.     

[2‐(Anilino­methyl)­phenyl]­di­phenyl­phosphine and {2‐[(N‐methyl­anilino)­methyl]­phenyl}di­phenyl­phosphine

The title compounds, Ph₂PCH₂N(H)Ph or C₂₅H₂₂NP and Ph₂PCH₂N(CH₃)Ph or C₂₆H₂₄NP, respectively, are isomorphous, with calculated theoretical Tolman angles of 174 and 182°.     

Bis(μ‐di‐2‐pyridyl­aminato 1‐oxide)­bis­[(tri­fluoro­acetato)copper(II)] aceto­nitrile disolvate

The crystal structure of the title compound, [Cu₂(C₂F₃O₂)₂(C₁₀H₈N₃O)₂]·2CH₃CN, contains discrete [Cu₂(CF₃COO)₂(O‐dpa)₂] mol­ecules (O‐dpaH is di‐2‐pyridyl­amine 1‐oxide) which have imposed crystallographic twofold symmetry and an aceto­nitrile mol­ecule of solvation. The O‐dpa⁻ ligand is both bidentate and bridging, linking two Cu atoms with a separation of 3.4270 (11) Å. Each Cu atom is surrounded by four coordinated atoms that are almost coplanar, with dimensions Cu—N = 1.940 (2) and 1.984 (3) Å, and Cu—O = 1.912 (2) and 1.945 (2) Å.     

{3,3′‐[2,2′‐(Ethylenedioxy)dibenzyl­idene]bis(S‐methyl dithiocarbazate)}­nickel(II)

The tetradentate N₂S₂ Schiff base ligand 3,3′‐[2,2′‐(ethyl­ene­di­oxy)di­benzyl­idene]­bis­(S‐methyl di­thio­car­ba­zate) (H₂L), prepared by the condensation of S‐methyl di­thio­carb­aza­te with 1,4‐bis(2‐formyl­phenyl)‐1,4‐dioxa­butane in a 1:2 molar ratio, reacts with nickel acetate to form the title neutral metal complex, [Ni(C₂₀H₂₀N₄O₂S₄)]. The X‐ray structure of the complex shows a distorted square‐planar geometry around the Ni atom. The monomeric units are weakly associated into dimers via a long Ni?S interaction [3.569 (1) Å]. These dimeric units are then linked by C—H?S intermolecular contacts to form a polymeric chain along the a axis.     

(μ‐2,6‐Bis{[(2‐hydroxy­phenyl)­(2‐pyri­dyl­methyl)­amino]­methyl}‐4‐methyl­phenolato)­bis­[di­aqua­nickel(II)] ace­tate dimethyl­formamide 0.75‐hy­drate

The binuclear cation of the title compound, [Ni₂(C₃₃H₂₉­N₄O₃)(H₂O)₄]C₂H₃O₂·C₃H₇NO·0.75H₂O, was synthesized as a model for the active site of urease. Two tridentate halves of the symmetrical 2,6‐bis{[(2‐hydroxy­phenyl)(2‐pyridyl­methyl)­amino]­methyl}‐4‐methyl­phenolate (BPPMP^3?) ligand are arranged in a meridional fashion around the two Ni^II ions, with the phenoxo O atom bridging the Ni^II ions. The cation has an approximate twofold rotation axis running through the C—O bond of the bridging phenolate group. Four water mol­ecules complete the octahedral environment of each Ni^II ion.     

Bis{μ‐[6‐(hydroxy­methyl)‐2‐pyridyl]­methano­lato‐κ3N,O:O}bis{[2,6‐bis­(hydroxy­methyl)­pyridine‐κ3O,N,O′]copper(II)} di­acetate

The title dinuclear Cu^II complex, [Cu₂(C₇H₈NO₂)₂(C₇H₉NO₂)₂](CH₃COO)₂, has been synthesized by the reaction of Cu(CH₃COO)₂·H₂O with pdmH₂ (pdmH₂ is pyridine‐2,6‐diyldi­methanol) in the presence of tetra­butyl­ammonium hydro­xide. The title complex contains a centrosymmetric Cu₂O₂ core and each Cu^II atom has distorted octahedral geometry. Molecular [Cu₂(pdmH)₂(pdmH₂)]²⁺ cations are connected by hydrogen bonds involving the CH₃COO⁻ anions, forming one‐dimensional chains along the a axis.     

5‐(2‐Chloro­phenyl­diazenyl)­salicyl­aldehyde and 4‐(2‐chloro­phenyl­diazenyl)‐2‐{[tris­(hydroxy­methyl)­methyl]­amino­methyl­ene}cyclo­hexa‐3,5‐dien‐1(2H)‐one

The mol­ecule of the former title compound, C₁₃H₉ClN₂O₂, (I), is nearly planar, with an intramolecular O⋯O hydrogen bond of 2.692 (2) Å. The latter title compound, C₁₇H₁₈ClN₃O₄, (II), exists in the keto–amine tautomeric form, with a strong intramolecular hydrogen bond of 2.640 (2) Å between the O and N atoms, the H atom being bonded to the N atom. The azo­benzene moieties of both mol­ecules have trans configurations, and the dihedral angle between the planes of the two aromatic rings is 4.1 (1)° in (I) and 9.9 (1)° in (II). The N—H⋯O hydrogen‐bonded rings are almost planar and coupled with the cyclo­hexa­diene rings in (II).     

[N,N‐Bis(2‐hydroxy­ethyl)­di­thio­car­bamato‐S]­bis­(tri­phenyl­phosphine‐P)­copper(I) tri­phenyl­phosphine solvate

In the title compound, [Cu(C₅H₁₀NO₂S₂)(C₁₈H₁₅P)₂]·C₁₈H₁₅P, the Cu atom is in a distorted tetrahedral coordination, with two tri­phenyl­phosphine P atoms and two S atoms from an N,N‐bis(2‐hydroxy­ethyl)­di­thio­carbamate ligand occupying the vertices. The crystal structure is characterized by alternate layers of complex and tri­phenyl­phosphine mol­ecules.     

Bis­[μ‐3{5}‐(2‐pyridyl)­pyrazolido]­bis­[(aceto­nitrile)copper(II)] diperchlorate

The title compound, [Cu₂(C₈H₆N₃)₂(C₂H₃N)₂](ClO₄)₂, con­tains a centrosymmetric dinuclear dication, with square‐pyrami­dal Cu^II centres linked by two 1,2‐pyrazolide bridging groups. There is a weak apical interaction between each Cu ion and a perchlorate O atom.     

Di­chloro­bis(1,2‐phenyl­enedi­amine)­nickel(II)

The title compound, [NiCl₂(C₆H₈N₂)₂], contains centrosymmetric mol­ecules with two phenyl­ene­di­amine ligands coordinated in a bidentate fashion. The Ni—N distances are 2.088 (1) and 2.096 (1) Å, and the Ni—Cl distance of 2.4635 (4) Å. The plane of each phenyl­enedi­amine mol­ecule makes a dihedral angle of 26.53 (7)° with the NiN₄ plane. Extensive hydrogen bonding leads to distinct cleavage in the bc plane.     

Racemic 3,5‐di­chloro‐2‐{[(1‐phenyl­ethyl)­imino]­methyl}phenol

The title compound, (RS)‐3,5‐di­chloro‐2‐{[(1‐phenyl­ethyl)­imino]­methyl}phenol, C₁₅H₁₃Cl₂NO, was synthesized from racemic 1‐phenyl­ethyl­amine and 3,5‐di­chloro­salicyl­aldehyde. The π‐conjugate system around the imine group is essentially planar in the phenol–imine tautomer. Intramolecular O⋯N hydrogen‐bond and intermolecular C—H⋯π interactions are present in the crystal structure.     

3‐Hydro­xy‐6‐[(4‐hydroxy­phenyl­amino)­methyl­ene]­cyclo­hexa‐2,4‐dienone and 2‐hydroxy‐6‐[(4‐hydroxy­phenyl­amino)­methyl­ene]­cyclo­hexa‐2,4‐dienone

The title compounds, both C₁₃H₁₁NO₃, exist as the keto–amine tautomers, and the formal hydroxyl H atoms, which display strong intramolecular hydrogen bonds, are located on the N atoms. This is a verification of the preference for the keto–amine tautomeric form in the solid state. The 2‐hydroxy isomer has two independent mol­ecules, with the mol­ecules linked by intramolecular N—H⋯O and O—H⋯O and intermolecular O—H⋯O hydrogen bonds into three‐dimensional networks.     

Ethyl N‐[2‐(hydroxy­acetyl)­phenyl]­carbamate,ethyl N‐[2‐(hydroxy­acetyl)‐4‐iodo­phenyl]­carbamate and ethyl N‐[2‐(hydroxy­acetyl)‐4‐methyl­phenyl]­carbamate

In ethyl N‐[2‐(hydroxy­acetyl)phenyl]carbamate, C₁₁H₁₃NO₄, all of the non‐H atoms lie on a mirror plane in the space group Pnma; the mol­ecules are linked into simple chains by a single C—H⋯O hydrogen bond. The mol­ecules of ethyl N‐[2‐(hydroxy­acetyl)‐4‐iodo­phenyl]carbamate, C₁₁H₁₂INO₄, are linked into sheets by a combination of O—H⋯I and C—H⋯O hydrogen bonds and a dipolar I⋯O contact. Ethyl N‐­[2‐(hydroxy­acetyl)‐4‐methyl­phenyl]carbamate, C₁₂H₁₅NO₄, crystallizes with Z′ = 2 in the space group P; pairs of mol­ecules are weakly linked by an O—H⋯O hydrogen bond and these aggregates are linked into chains by two independent aromatic π–π stacking inter­actions.     

Redetermination of hexa­carbonyl­(η5‐cyclo­penta­dienyl)­bis(μ3‐selenido)­diiron(II)­cobalt(II)

The structure of the title compound, hexa­carbonyl‐1κ³C,2κ³C‐[3(η⁵)‐cyclo­penta­dienyl]­bis(μ₃‐selenido)­diiron(II)­cobalt(II),[CoFe₂(μ₃‐Se)₂(C₅H₅)(CO)₆], was redetermined at room temperature and the correct C2/c space group was assumed instead of the previously reported P space group [Mathur et al. (1995). Organometallics, 14 , 2115–2118]. Analysis of the literature data showed that the previously reported triclinic parameters correspond to a primitive subcell of the actual monoclinic C‐centred cell with cell dimensions close to those found by us. The title compound appeared to be isostructural with the sulfur–selenium analogue.     

[1,6‐Bis(2‐pyridyl­methyl)‐2,5‐di­aza­hexane‐κ4N]­chlorocopper(II) per­chlorate

The title mononuclear copper(II) compound, [CuCl(C₁₆H₂₂­N₄)]­ClO₄, shows a slightly tetrahedrally distorted square‐pyramidal coordination with the chlorine ligand at the apical position. The directions of the two N—Me bond axes are syn to the Cu—Cl bond.     

(E)‐5‐[(4‐Nitro­phenyl­hydrazono)­phenyl­acetyl]‐3‐phenyl­isoxazole

The title compound, C₂₃H₁₆N₄O₄, can be considered as consisting of two connected fragments: a nitro­phenyl­hydrazone moiety, which assumes an E configuration, and an isoxazole moiety. In this latter fragment, the weak π‐electron delocalization shortens the carbonyl–isoxazole O?O distance [2.643 (2) Å] to less than the van der Waals radii sum.     

Bis[bis­(2‐pyridylcarbon­yl)­aminato]­iron(III) perchlorate acetonitrile disolvate

The title compound, [Fe(C₁₂H₈N₃O₂)₂]ClO₄·2C₂H₃N, contains Fe^III in a distorted octa­hedral coordination environment, with the Fe—N(pyridine) bonds significantly longer than the Fe—N(amine) bonds. The crystal packing involves a bifurcated C—H⋯(O,O) contact that is also found in all other [M(C₁₂H₈N₃O₂)₂] complexes reported previously.