Auxiliary ligand field dominated single-molecule magnets of a series of indole-derivative ß-diketone mononuclear Dy(iii) complexes.

A series of four indole-derivative ß-diketone mononuclear dysprosium complexes, namely, Dy(EIFD)3(bpy)·CH3CN (), Dy(EIFD)3(phen)·CH2Cl2 (), Dy(EIFD)3(dpq)·CH2Cl2 (), and Dy(EIFD)3(dppz)·2H2O () (EIFD = 1-(1-ethyl-1H-indol-3-yl)-4,4,4-trifluorobutane-1,3-dione, bpy = 2,2'-bipyridine, phen = 1,10-phenanthroline, dpq = dipyrazine[2,3-f:2',3'-h]quinoxaline, dppz = dipyrido[3,2-a:2',3'-c]phenazine) have been isolated by reactions of EIFD, DyCl3·6H2O and a series of auxiliary ligands. X-ray crystallographic analysis reveals that complexes are all eight-coordinated mononuclear structures. Magnetic studies indicate that complexes are all single-molecule magnets. Notably, the auxiliary ligands play an essential role in regulating their magnetism. The corresponding structural and magnetic parameters have been discussed in detail.

Ruthenium complexes bearing an unsymmetrical pincer ligand with a 2-hydroxypyridylmethylene fragment: active catalysts for transfer hydrogenation of ketones.

Five ruthenium(ii) complexes were synthesized, including (HO-C5H3N-CH2-C5H3N-C5H4N)Ru(PPh3)Cl2 (3), [(HO-C5H3N-CH2-C5H3N-C5H4N)Ru(PPh3)2Cl][PF6] (4) and [(HO-C5H3N-CH2-C5H3N-C5H4N)Ru(PPh3)2OH][PF6] (5) bearing an unsymmetrical pincer NNN ligand with a 2-hydroxypyridylmethylene fragment, and [(CH3O-C5H3N-CH2-C5H3N-C5H4N)2Ru][Cl]2 (6) and [(CH3O-C5H3N-CH2-C5H3N-C5H4N)2Ru][PF6]2 (7) containing 2-methoxypyridylmethylene moieties. 4 reacts with H2O at room temperature to give 5 whose crystal structure reveals the existence of intramolecular hydrogen-bonding between its two -OH groups. 3 exhibits high catalytic activity for transfer hydrogenation of ketones.

Towards full-color-tunable emission of two component Eu(III)-doped Gd(III) coordination frameworks by the variation of excitation light.

A series of pyrazine-2,3,5,6-tetracarboxylate alkali-lanthanide coordination frameworks, namely [NaLn(pztc)(H2O)3]·H2O [Ln = Ce (), Sm (), Eu (), Gd () and Tb (); H4pztc = pyrazine-2,3,5,6-tetracarboxylic acid], have been synthesized by reacting Ln(NO3)3·6H2O with H4pztc in the presence of NaOH at room temperature. X-ray crystallographic analysis reveals that complexes are isostructural, featuring three-dimensional (3D) networks with a unique (4(11)·6(8)·8(2))(4(3)·6(2)·8)(4(3)) topology in which the ligand displays a novel µ7-coordination mode. The photoluminescence (PL) spectra in the solid state reveal that complexes , and exhibit the characteristic luminescence of Sm(iii), Eu(iii) and Tb(iii) ions, respectively, while complex displays a broad band in the range of 400-650 nm (λmax = 505 nm) which exhibits about 103 nm red-shift and enhancement compared to the band of the free ligand. Further, the isostructural two-component Eu(iii)-doped Gd(iii) complexes realize color-tunable luminescence from red to yellow, white, green and blue by the variation of excitation wavelengths. They represent the first example of full-color-tunable emission in lanthanide coordination frameworks by the variation of excitation light.

Efficient red emission from PMMA films doped with 5,6-DTFI europium(III) complexes: synthesis, structure and photophysical properties.

A new ß-diketone, 5,6-dimethoxy-2(2,2,2-trifluoroethyl)-1-indone (5,6-DTFI), has been designed and synthesized. Two series of four 5,6-DTFI Sm(3+) and Eu(3+) complexes, namely, Eu(5,6-DTFI)3(H2O)2 (1), Eu(5,6-DTFI)3(Phen) (2), Sm(5,6-DTFI)3(H2O)2 (3) and Sm(5,6-DTFI)3(Phen) (4) (Phen = 1,10-phenanthroline), have been isolated. X-ray diffraction analysis reveals that all complexes 1-4 are of mononuclear structures. Luminescent and phosphorescent spectra of complexes 1-4 show strong characteristic emissions of the corresponding Eu(3+) and Sm(3+) ions. Upon complexes 1 and 2 were doped into the poly(methylmethacrylate) (PMMA) forming the films, the PMMA polymer matrix acting as a co-sensitizer for Eu(3+) ion enhances the luminescent lifetimes, overall quantum yields and the thermal stability in comparison with the precursor complexes.

NIR luminescence and catalysis of multifarious salen type ytterbium complexes modulated by anions.

A series of five N,N'-bis(2-hydroxy-3-methoxybenzylidene)-1,3-propanediamine (H2L) ytterbium complexes, namely, [Yb(H2L)2(CH3OH)](ClO4)3 (1), [Yb(H2L)(NO3)3]2·CH2Cl2 (2), [Yb(H2L)2(NO3)]2(PF6)4·4H2O·2CH2Cl2 (3), [Yb(H2L)(OAc)2]2(PF6)2·4CH2Cl2 (4) and [Yb3L'3(OH)2Cl(H2O)5]Cl3·4H2O (5) (HL' = 2-hydroxy-3-methoxybenzaldehyde), have been synthesized by reactions of H2L with multifarious Yb(iii) salts. X-ray diffraction analysis reveals that complex 1 shows a unique mononuclear structure constructed from two chelating H2L ligands in crossover mode. Complex 2 exhibits a dinuclear structure bridged by two H2L ligands. Complexes 3 and 4 possess two novel dinuclear structures linked by NO3(-) and OAc(-) anions, respectively. Complex 5 displays a trinuclear structure supported by three L' and two OH(-) anions. Noticeable, complex 3 can be transformed from 2 by introducing (NH4)(PF6). The PF6(-) counterion plays an essential role in steering the structural transformation. The anions dominate the final structures of 1-5. All complexes 1-5 exhibit NIR luminescence, which can be rationalized on the basis of different structural effects. Preliminary catalytic studies reveal that all complexes 1-5 are able to catalyze effectively a typical Henry reaction with good yields.

Systematic study on the structures of salen type lanthanide complexes tuned by lanthanide contraction and corresponding luminescence.

Two types of N,N'-bis(salicylidene)-1,3-propanediamine (H2L) lanthanide complexes, viz. [Ln(NO3)3(H2L)2]·0.2CH3OH [Ln = La (1), Ce (2) and Pr (3)] and [Ln(NO3)3(H2L)2]2·CH2Cl2·CH3OH [Ln = Nd (4), Sm (5), Eu (6), Gd (7), Tb (8) and Yb (9)], have been isolated by reactions of H2L with Ln(NO3)3·6H2O. X-ray crystallographic and PXRD analysis reveal that 1-3 are isomorphic possessing a novel one-dimensional (1D) ladder-like double-chain structure. Complexes 4-9 are isostructural exhibiting a discrete dinuclear structure. Luminescent analysis reveals the lanthanide ion and ligand-centered co-luminescence for 5, 6 and 8, which are attributed to the incomplete energy transfer from the triplet state of H2L to the resonance energy level of the corresponding Ln(iii) ion. Further, the characteristic near infrared (NIR) luminescence of Nd(iii) and Yb(iii) ions for complexes 4 and 9 have been revealed.

Three alkaline-earth metal complexes with 3D networks constructed from a 7,7,8,8-tetracyanoquinodimethane ligand: synthesis, structure and electrochemical properties.

Three new 7,7,8,8-tetracyanoquinodimethane (TCNQ) alkaline-earth metal complexes, namely {[M2(TCNQ)3(H2O)6]·TCNQ}n (M = Ca (1), Sr (2) and Ba (3)) have been synthesized by salt elimination reactions. X-ray crystallographic analysis reveals that complexes 1, 2 and 3 are isomorphic featuring a unique 3D structure. Cyclic and differential pulse voltammograms for complexes 1-3 show a reversible one-electron oxidation and a reversible one-electron reduction within the electrochemical window of CH3CN. Their electrochemical HOMO-LUMO gap and reversibility are examined.

Chemical adaptability: the integration of different kinds of matter into giant molecular metal oxides.

Unique properties of the two giant wheel-shaped molybdenum-oxides of the type {Mo(154)}≡[{Mo(2)}{Mo(8)}{Mo(1)}](14) (1) and {Mo(176)}≡[{Mo(2)}{Mo(8)}{Mo(1)}](16) (2) that have the same building blocks either 14 or 16 times, respectively, are considered and show a "chemical adaptability" as a new phenomenon regarding the integration of a large number of appropriate cations and anions, for example, in form of the large "salt-like" {M(SO(4))}(16) rings (M = K(+), NH(4)(+)), while the two resulting {Mo(146)(K(SO(4)))(16)} (3) and {Mo(146)(NH(4)(SO(4)))(16)} (4) type hybrid compounds have the same shape as the parent ring structures. The chemical adaptability, which also allows the integration of anions and cations even at the same positions in the {Mo(4)O(6)}-type units of 1 and 2, is caused by easy changes in constitution by reorganisation and simultaneous release of (some) building blocks (one example: two opposite orientations of the same functional groups, that is, of H(2)O{Mo=O} (I) and O={Mo(H(2)O)} (II) are possible). Whereas Cu(2+) in [(H(4)Cu(II)(5))Mo(V)(28)Mo(VI)(114)O(432)(H(2)O)(58)](26-) (5 a) is simply coordinated to two parent O(2-) ions of {Mo(4)O(6)} and to two fragments of type II, the SO(4)(2-) integration in 3 and 4 occurs through the substitution of two oxo ligands of {Mo(4)O(6)} as well as two H(2)O ligands of fragment I. Complexes 3 and now 4 were characterised by different physical methods, for example, solutions of 4 in DMSO with sophisticated NMR spectroscopy (EXSY, DOSY and HSQC). The NH(4)(+) ions integrated in the cluster anion of 4 "communicate" with those in solution in the sense that the related H(+) ion exchange is in equilibrium. The important message: the reported "chemical adaptability" has its formal counterpart in solutions of "molybdates", which can form unique dynamic libraries containing constituents/building blocks that may form and break reversibly and can lead to the isolation of a variety of giant clusters with unusual properties.

2-(2-Hy-droxy-3-meth-oxy-phen-yl)-1H-benzimidazol-3-ium perchlorate.

In the title mol-ecular salt, C(14)H(13)N(2)O(2) (+)·ClO(4) (-), the ring systems in the cation are almost coplanar [dihedral angle = 5.53 (13)°]. Intra-molecular N-H⋯O and O-H⋯O hydrogen bonds generate S(6) and S(5) rings, respectively. In the crystal, the two H atoms involved in the intra-molecular hydrogen bonds also participate in inter-molecular links to acceptor O atoms of the perchlorate anions. A simple inter-molecular N-H⋯O bond also occurs. Together, these form a double-chain structure along [101].

Trichlorido{µ-6,6'-dimeth-oxy-2,2'-[cyclo-hexane-1,2-diylbis(nitrilo-methanylyl-idene)]diphenolato}dimethano-l-copper(II)samarium(III).

In the title hetero-dinuclear complex, [CuSm(C(22)H(24)N(2)O(4))Cl(3)(CH(3)OH)(2)], the Cu(II) cation is N,N',O,O'-chelated by a 6,6'-dimeth-oxy-2,2'-[cyclo-hexane-1,2-diylbis(nitrilo-methanylyl-idene)]diphenolate ligand, and one Cl(-) anion further coordinates to the Cu(II) cation to complete the distorted square-pyramidal coordination geometry, while the Sm(III) cation is chelated by four O atoms from the same ligand, and is further coordinated by two methanol mol-ecules and two Cl(-) anions in an bicapped trigonal-prismatic geometry. Intra- and inter-molecular O-H⋯Cl hydrogen bonds are present in the structure.

A second ortho-rhom-bic polymorph of 4-(Pyridin-4-ylmethoxy)phenol [corrected].

The crystal structure of the title compound, C(12)H(11)NO(2), represents a new ortho-rhom-bic polymorph II of the previously reported ortho-rhom-bic form I [Zhang et al. (2009 ▶) Acta Cryst. E65, o3160]. In polymorph II, the six-membered rings form a dihedral angle of 13.8 (1)° [71.6 (1)° in I], and O-H⋯N hydrogen bonds link mol-ecules into chains along [100], whereas the crystal structure of I features hydrogen-bonded centrosymmetric dimers.

Synthesis, crystal structure, and luminescent properties of 2-(2,2,2-trifluoroethyl)-1-indone lanthanide complexes.

A new ß-diketone, 2-(2,2,2-trifluoroethyl)-1-indone (TFI), which contains a trifluorinated alkyl group and a rigid indone group, has been designed and employed for the synthesis of two series of new TFI lanthanide complexes with a general formula [Ln(TFI)(3)L] [Ln = Eu, L = (H(2)O)(2) (1), bpy (2), and phen (3); Ln = Sm, L = (H(2)O)(2) (4), bpy (5), and phen (6); bpy = 2,2'-bipyridine, phen = 1,10-phenanthroline]. X-ray crystallographic analysis reveals that complexes 1-6 are mononuclear, with the central Ln(3+) ion eight-coordinated by six oxygen atoms furnished by three TFI ligands and two O/N atoms from ancillary ligand(s). The room-temperature photoluminescence (PL) spectra of complexes 1-6 show strong characteristic emissions of the corresponding Eu(3+) and Sm(3+) ions, and the substitution of the solvent molecules by bidentate nitrogen ligands essentially enhances the luminescence quantum yields and lifetimes of the complexes.

Triethyl-ammonium (2R,3R)-2,3-bis-(benzo-yloxy)-3-carb-oxy-propano-ate.

In the anion of the title salt, C(6)H(16)N(+)·C(18)H(13)O(8) (-), one of the carboxyl groups is deprotonated. Its O atoms are involved in inter-molecular hydrogen bonding with the carboxyl group of an adjacent anion and the amino group of an adjacent cation. The two benzoyloxy rings are oriented with respect to each other at a dihedral angle of 79.46 (6)°.

Bis[1,1'-(1,3-phenyl-enedimethyl-ene)di(1H-imidazol-3-ium)] ß-octa-molybdate.

In the title compound, (C(14)H(16)N(4))(2)[Mo(8)O(26)], the ß-octa-molybdate anion is centrosymmetric. N-H⋯O hydrogen bonds link the diimidazolium cations and the polyoxidoanions into a chain structure along [100]. π-π inter-actions between the imidazole rings and between the imidazole and benzene rings [centroid-centroid distances = 3.611 (2) and 3.689 (3) Å, respectively] connect the chains.

Aqua-cyanido{6,6'-dimeth-oxy-2,2'-[1,2-phenyl-enebis(nitrilo-methanylyl-idene)]diphenolato}cobalt(III) acetonitrile hemisolvate.

In the title complex, [Co(C(22)H(18)N(2)O(4))(CN)(H(2)O)]·0.5CH(3)CN, the Co(III) cation is N,N',O,O'-chelated by a 6,6'-dimeth-oxy-2,2'-[1,2-phenyl-enebis(nitrilo-methanylyl-idene)]diphenolate dianion, and is further coordinated by a cyanide anion and a water mol-ecule in the axial sites, completing a distorted octa-hedral coordination geometry. In the crystal, pairs of bifurcated O-H⋯(O,O) hydrogen bonds link adjacent mol-ecules, forming centrosymmetric dimers. The acetonitrile solvent mol-ecule shows 0.5 occupancy.

4-(2,2-Difluoro-1,3-benzodioxol-4-yl)-1H-pyrrole-3-carbonitrile.

In the title compound, C(12)H(6)F(2)N(2)O(2), the 2,2-difluoro-1,3-benzodioxole ring system is approximately planar [maximum deviation = 0.012 (2) Å] and its mean plane is twisted with respect to the pyrrole ring, making a dihedral angle of 2.51 (9)°. In the crystal, N-H⋯N hydrogen bonds link the mol-ecules into chains running along the a axis. π-π stacking is also observed between parallel benzene rings of adjacent mol-ecules, the centroid-centroid distance being 3.7527 (13) Å.

Ethane-1,2-diaminium (R)-2-[4-(1-carboxyl-atoeth-oxy)phen-oxy]acetate.

In the title compound, C(2)H(10)N(2) (2+)·C(11)H(10)O(6) (2-), the two acetate groups of the cation form dihedral angles of 74.2 (4) and 63.9 (5)° with the central benzene ring. In the crystal, N-H⋯O hydrogen bonds link the cations and anions into layers parallel to the ab plane.

3-Benzyl-sulfanyl-1H-1,2,4-triazol-5-amine.

In the title mol-ecule, C(9)H(10)N(4)S, the dihedral angle between the benzene and triazole rings is 81.05 (5)°. In the crystal, N-H⋯N hydrogen bonds link the mol-ecules into infinite zigzag chains along [010].

Poly[tetra-aquadi-µ(4)-oxalato-potassium-ytterbium(III)].

In the title compound, [KYb(C(2)O(4))(2)(H(2)O)(4)](n), the Yb(III) ion lies on a site of [Formula: see text] symmetry in a dodeca-hedral environment defined by eight O atoms from four oxalate ligands. The K atom lies on a different [Formula: see text] axis and is coordinated by four O atoms from four oxalate ligands and four water O atoms. The oxalate ligand has an inversion center at the mid-point of the C-C bond. The metal ions are linked by the oxalate ligands into a three-dimensional framework. O-H⋯O hydrogen bonding is present in the crystal structure.

1,1'-[(Biphenyl-4,4'-di-yl)bis-(methyl-ene)]di-1H-imidazol-3-ium tetra-chlorido-mercurate(II).

In the title compound, (C(20)H(20)N(4))[HgCl(4)], the Hg(II) ion is four-coordinated in a tetra-hedral environment defined by four chloride ions. The dihedral angle between the two phenyl rings is 32.83 (15)°. The protonated 1,1'-[(biphenyl-4,4'-di-yl)bis-(meth-yl-ene)]di-1H-imidazol-3-ium cations, showing a cis conformation, link the [HgCl(4)](2-) anions into an R(4) (4)(42) motif via N-H⋯Cl hydrogen bonds.