Metalation Triggers Single Crystalline Order in a Porous Solid.

We report the dramatic triggering of structural order in a Zr(IV)-based metal-organic framework (MOF) through docking of HgCl2 guests. Although as-made crystals were unsuitable for single crystal X-ray diffraction (SCXRD), with diffraction limited to low angles well below atomic resolution due to intrinsic structural disorder, permeation of HgCl2 not only leaves the crystals intact but also resulted in fully resolved backbone as well as thioether side groups. The crystal structure revealed elaborate HgCl2-thioether aggregates nested within the host octahedra to form a hierarchical, multifunctional net. The chelating thioether groups also promote Hg(II) removal from water, while the trapped Hg(II) can be easily extricated by 2-mercaptoethanol to reactivate the MOF sorbent.

Convenient detection of Pd(II) by a metal-organic framework with sulfur and olefin functions.

A highly specific, distinct color change in the crystals of a metal-organic framework with pendant allyl thioether units in response to Pd species was discovered. The color change (from light yellow to orange/brick red) can be triggered by Pd species at concentrations of a few parts per million and points to the potential use of these crystals in colorimetric detection and quantification of Pd(II) ions. The swift color change is likely due to the combined effects of the multiple functions built into the porous framework: the carboxyl groups for bonding with Zn(II) ions to assemble the host network and the thioether and alkene functions for effective uptake of the Pd(II) analytes (e.g., via the alkene-Pd interaction). The resultant loading of Pd (and other noble metal) species into the porous solid also offers rich potential for catalysis applications, and the alkene side chains are amenable to wide-ranging chemical transformations (e.g., bromination and polymerization), enabling further functionalization of the porous networks.

Bis(1,10-phenanthroline-κN,N')[2-(4-sulfonato-anilino)acetato-κO]copper(II) dihydrate.

In the title compound, [Cu(C(8)H(7)NO(5)S)(C(12)H(8)N(2))(2)]·2H(2)O, the Cu(II) ion is coordinated by four N atoms from two 1,10-phenanthroline (phen) ligands and one O atom from a 2-(4-sulfonato-anilino)acetate (spia) ligand in a distorted square-pyramidal geometry. Inter-molecular N-H⋯O and O-H⋯O hydrogen bonds, as well as π-π inter-actions between phen ligands and between phen and spia ligands [centroid-centroid distances = 3.663 (3), 3.768 (3) and 3.565 (3) Å], result in a three-dimensional supra-molecular structure.

Bis(µ-2-phenyl-quinoline-4-carboxyl-ato)bis-[aqua-(1,10-phenanthroline)(2-phenyl-quinoline-4-carboxyl-ato)manganese(II)] dihydrate.

In the centrosymmetric dinuclear title complex, [Mn(2)(C(16)H(10)NO(2))(4)(C(12)H(8)N(2))(2)(H(2)O)(2)]·2H(2)O, the Mn(II) cation is in a distorted octa-hedral coordination geometry defined by two N atoms from a 1,10-phenanthroline ligand, one water O atom and three O atoms from three 2-phenyl-quinoline-4-carboxyl-ate anions. A pair of 2-phenyl-quinoline-4-carboxyl-ate anions bridge two Mn cations, forming the dinuclear mol-ecule. An intra-moleculr O-H⋯O hydrogen bond occurs. Inter-molecular O-H⋯O and O-H⋯N hydrogen bonds are present in the crystal structure.

Bis(µ-2-phenyl-quinoline-4-carboxyl-ato)-κO,O':O;κO:O,O'-bis-[(2,2'-bipyridine-κN,N')(2-phenyl-quinoline-4-carboxyl-ato-κO,O')cadmium(II)].

The neutral binuclear title complex, [Cd(2)(C(16)H(10)NO(2))(4)(C(10)H(8)N(2))(2)], is centrosymmetric, with the inversion center generating the central (µ-O)(2)Cd(2) bridge. The Cd(II) ion is in a strongly distorted CdN(2)O(5) penta-gonal-bipyramidal geometry, defined by two N atoms from one 2,2'-bipyridine ligand and five O atoms from three 2-phenyl-quinoline-4-carboxyl-ate ligands, one monodentate, two bidentate. Weak inter-molecular π-π inter-actions [centroid-centroid distance = 3.712 (3) Å] help to establish the packing of the structure.

catena-Poly[cadmium-bis-(µ-N,N-dimethyl-dithio-carbamato-κS,S':S)].

In the title compound, [Cd(C(3)H(6)NS(2))(2)](n), the Cd(II) atom, lying on a twofold rotation axis, is coordinated by six S atoms from four different N,N-dimethyl-dithio-carbamate ligands in a distorted octa-hedral geometry. The bridging of S atoms of the ligands leads to the formation of a one-dimensional structure along [001].

Diaqua-bis-{2-hy-droxy-5-[(pyridin-2-yl)methyl-idene-amino]-benzoato-κN,N'}zinc(II) dihydrate.

The complex mol-ecule of the title compound, [Zn(C(13)H(9)N(2)O(3))(2)(H(2)O)(2)]·2H(2)O, has 2 symmetry with the Zn(II) cation located on a twofold rotation axis. The Zn cation is N,N'-chelated by two 5-[(pyridin-2-yl)methyl-idene-amino]-2-hy-droxy-benzoate anions and coordinated by two water mol-ecules in a distorted octa-hedral geometry. Within the anionic ligand, the pyridine ring is oriented at a dihedral angle of 49.54 (10)° with respect to the benzene ring. The carboxyl-ate group of the anionic ligand is not involved in coordination but is O-H⋯O hydrogen bonded to the coordinated and uncoordinated water mol-ecules. Weak inter-molecular C-H⋯O hydrogen bonding is also present in the crystal structure.

Diaqua-bis-{2-hy-droxy-5-[(pyridin-2-yl)methyl-idene-amino]-benzoato-κN,N'}nickel(II) dihydrate.

In the title complex, [Ni(C(13)H(9)N(2)O(3))(2)(H(2)O)(2)]·2H(2)O, the Ni(II) atom, located on a twofold rotation axis, is in a distorted octa-hedral geometry, defined by four N atoms from two 2-hy-droxy-5-[(pyridin-2-yl)methyl-idene-amino]-benzoate ligands and two O atoms from two water mol-ecules. In the crystal, inter-molecular O-H⋯O hydrogen bonds link the complex mol-ecules and uncoordinated water mol-ecules into a three-dimensional network. Intra-molecular O-H⋯O hydrogen bonds are present between the hy-droxy and carboxyl-ate groups.

(µ-4,4'-Bipyridine-κN:N')bis-[bis-(N,N-dimethyl-dithio-carbamato-κS,S')zinc(II)].

The title dinuclear Zn(II) complex, [Zn(2)(C(3)H(6)NS(2))(4)(C(10)H(8)N(2))], is centrosymmetric; the mid-point of the C-C bond linking the two pyridine rings is located on an inversion center. The pyridine N atom coordinates to the Zn(II) cation, which is also chelated by two dimethyl-dithio-carbamate anions, giving a trigonal-bipyramidal ZnNS(4) geometry. Weak inter-molecular C-H⋯S hydrogen bonding is present in the crystal structure.

Improving the Loading Capacity of Metal-Organic Framework Thin Films Using Optimized Linkers.

The large surface area of metal-organic frameworks (MOFs) sparks great interest for their use in storage applications. While the bulk of MOF applications focuses on incorporation of gases, we demonstrate that these highly porous frameworks are also well-suited for metal ion storage. For well-defined, highly oriented surface-anchored MOF thin films grown on modified gold surfaces using liquid-phase epitaxy (LPE), also referred to as SURMOFs, we determined the loading of two different types of MOF materials with a total of seven types of metal ions (Zn(2+), Ag(+), Pd(2+), Fe(3+), Cd(2+), Ni(2+), and Co(2+)). Measurements using a quartz crystal microbalance (QCM) allowed determination of loading capacities as well as diffusion constants in a quantitative fashion. The adsorption capacities were observed to be highly ion specific; the largest uptake was for Fe(3+) and Pd(2+) ions with six and four metal ions per MOF pore, respectively. By comparing results for SURMOFs fabricated from different types of linkers, we demonstrate that S-containing functionalities in particular drastically improve the storage capacity of MOFs for metal ions.

Room-temperature acetylene hydration by a Hg(II)-laced metal-organic framework.

Thiol (-SH) groups within a Zr(IV)-based metal-organic framework (MOF) anchor Hg(II) atoms; oxidation by H2O2 then leads to acidic sulfonate functions for catalyzing acetylene hydration at room temperature.