Aqua­{4,4′,6,6′-tetra­fluoro-2,2′-[(piperazine-1,4-di­yl)dimethyl­ene]diphenolato}copper(II)

In the title compound, [Cu(C18H16F4N2O2)(H2O)], the CuII atom shows a distorted square-pyramidal coordination geometry with the N,N′,O,O′-tetra­dentate piperazine–diphenolate ligand forming the basal plane. The apical site is occupied by the O atom of a coordinated water mol­ecule. Neighbouring complexes are associated through inter­molecular O—H⋯O and O—H⋯F hydrogen bonds between the water mol­ecule and a phenolate O atom or an F atom from an adjacent ligand, respectively, forming a centrosymmetric dimer. Dimers are linked by additional inter­molecular C—H⋯O and C—H⋯F hydrogen bonds, giving infinite chains propagating along the a axis

A monoclinic polymorph of 4,4′-dichloro-2,2′-(piperazine-1,4-diyl­dimethyl­ene)diphenol

The titile compound, C18H20Cl2N2O2, crystallizes as a monoclinic form in the space group P21/n, with Z′ = 1/2. It is polymorphic with the previously reported orthorhombic form [Kubono, Tsuno, Tani & Yokoi (2008). Acta Cryst. E64, o2309]. In the present polymorph, the mol­ecule lies on a crystallographic inversion centre at the piperazine ring centroid. An intra­molecular O—H⋯N hydrogen bond forms an S(6) ring motif. Inter­molecular C—H⋯O hydrogen bonding generates a C(5) chain motif propagating along the b axis, forming sheets parallel to (02) with a first-level graph set S(6)C(5)R 6 6(34)

Bis[μ-4,4′,6,6′-tetra­chloro-2,2′-(piperazine-1,4-diyldimethyl­ene)diphenolato]dicopper(II)

In the centrosymmetric dinuclear CuII title complex, [Cu2(C18H16Cl4N2O2)2], the CuII atom adopts a square-pyramidal geometry with a tetra­dentate ligand in the basal plane. The apical site is occupied by a phenolate O atom from an adjacent ligand, forming a dimer. The mol­ecular structure is stabilized by intra­molecular C—H⋯O and C—H⋯Cl hydrogen bonds

1,2-Bis[5-(9-ethyl-9H-carbazol-3-yl)-2-methyl­thio­phen-3-yl]-3,3,4,4,5,5-hexa­fluoro­cyclo­pentene

The title compound, C43H32F6N2S2, is a new symmetrical photochromic diaryl­ethene derivative with 9-ethyl­carbazol-3-yl substituents. The mol­ecule adopts a photoactive anti­parallel conformation [Irie (2000). Chem. Rev. 100, 1685–1716; Kobatake et al. (2002). Chem. Commun. pp. 2804–2805], with a dihedral angle between the mean planes of the two thio­phene rings of 56.23 (6)°. The distance between the two reactive C atoms is 3.497 (3) Å. In the crystal, two mol­ecules are associated through a pair of C—H⋯F inter­molecular hydrogen bonds, forming a centrosymmetric dimer. Dimers are linked by weak π–π inter­actions [centroid–centroid distance = 3.8872 (13) Å], forming chains along the c axis

Dynamical Excimer Formation in Rigid Carbazolophane via Charge Transfer State

Formation dynamics of intramolecular excimer in dioxa[3.3](3, 6)carbazolophane (CzOCz) was studied by time-resolved spectroscopic methods and computational calculations. In the ground state, the most stable conformer in CzOCz is the anti-conformation where two carbazole rings are in antiparallel alignment. No other isomers were observed even after the solution was heated up to 150 °C, although three characteristic isomers were found by the molecular mechanics calculation: the first is the anti-conformer, the second is the syn-conformer where two carbazole rings are stacked in the same direction, and the third is the int-conformer where two carbazole rings are aligned in an edge-to-face geometry. Because of the anti-conformation, the interchromophoric interaction in CzOCz is negligible in the ground state. Nonetheless, the intramolecular excimer in CzOCz was dynamically formed in an acetonitrile (MeCN) solution, indicating strong interchromophoric interaction and the isomerization from the anti- to syn-conformation in the excited state. The excimer formation in CzOCz is more efficient in polar solvents than in less polar solvents, suggesting the contribution of the charge transfer (CT) state to the excimer formation. The stabilization in the excited state is discussed in terms of molecular orbital interaction between two carbazole rings. The solvent-polarity-induced excimer formation is discussed in terms of the CT character in the int-conformation

Crystal structure of poly[(acetonitrile-κN)(μ3-7-{[bis(pyridin-2-ylmethyl)amino]methyl}-8-hydroxyquinoline-5-sulfonato-κ4N,O:O′:O′′)sodium]

In the title compound, [Na(C22H19N4O4S)(CH3CN)]n, the NaI atom adopts a distorted square-pyramidal coordination geometry, formed by one N and one O atom of the qunolinol moiety in the ligand, two O atoms of sulfonate moieties of two adjacent ligands and the N atom of the coordinated acetonitrile solvent. The NaI atom is located well above the mean basal plane of the square-based pyramid. The apical position is occupied by a sulfonate O atom of a neighboring ligand. Three N atoms of the bis(pyridin-2-ylmethyl)amine moiety in the ligand are not coordinated by the sodium atom. The molecule forms an intramolecular bifurcated O—H...[N(tertiary amine),N(pyridine)] hydrogen bond, generating S(6) and S(5) rings. In the crystal, four molecules are linked by four Na—O(sulfonato) bridged coordination bonds, forming a supramolecular centrosymmetric tetramer unit comprising an eight-membered ring, and generating a two-dimensional network sheet. The molecules of different sheets form intermolecular C—H...O hydrogen bonds, and thereby a three-dimensional network structure

Di-μ2-acetato-1:2κ2O:O′;2:3κ2O:O′-bis{μ2-4,4′-dichloro-2,2′-[2,2-dimethylpropane-1,3-diylbis(nitrilomethanylylidene)]diphenolato}-1:2κ6O,N,N′,O′:O,O′;2:3κ6O,O′:O,N,N′,O′-tricadmium

In the title linear homo-trinuclear complex, [Cd3(C19H18Cl2N2O2)2(C2H3O2)2], the central CdII atom is located on a centre of inversion and has a distorted octahedral coordination geometry formed by four O atoms from two bidentate/tetradentate Schiff base ligands and two O atoms from two bridging acetate ligands. The coordination geometry of the terminal CdII atom is square-pyramidal with the tetradentate part of the ligand in the basal plane and one O atom from an acetate ligand occupying the apical site. The six-membered CdN2C3 ring adopts a chair conformation. The acetate-bridged Cd...Cd distance is 3.3071 (2) Å. The crystal structure is stabilized by C—H...O hydrogen bonds, which form C(7) chain motifs and give rise to a two-dimensional supramolecular network structure lying parallel to the ab plane