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Jie-Peng Zhang

Publications and source records attributed to Jie-Peng Zhang.

17 recordsLinked to original sources
PubMed2006

Crystal engineering of binary metal imidazolate and triazolate frameworks.

This article summarizes the recent advances in the crystal growth, structural control strategies and diverse structures of the binary metal imidazolate and triazolate frameworks, which are the simplest systems for crystal engineering of two-, three- and four-connected coordination polymers.

Journal Article↗
PubMed2005

Temperature- or guest-induced drastic single-crystal-to-single-crystal transformations of a nanoporous coordination polymer.

Aside from a temperature-induced structural transformation, a new nanoporous coordination polymer [Ag6Cl(atz)4].OH.6H2O (Hatz = 3-amino-1,2,4,-triazole) comprised of interpenetrated Ag3(atz)2 coordination nets exhibits a single-crystal-to-single-crystal transformation of a 5-fold to 6-fold net interpenetration change triggered by guest desorption/absorption.

Crystallization↗
PubMed2005

Supramolecular isomerism within three-dimensional 3-connected nets: unusual synthesis and characterization of trimorphic copper(I) 3,5-dimethyl-1,2,4-triazolate.

Solvothermal treatments of acetonitrile, aqueous ammonia and copper(II) salts frequently yielded alpha-[Cu(mtz)](1)(Hmtz = 3,5-dimethyl-1,2,4-triazole) under different reaction conditions. However, two new supramolecular isomers of 1, namely beta-[Cu(mtz)](2) and gamma-[Cu(mtz)](3) were successfully isolated upon introducing 4,4'-bipyridine or nitrate as an additive. 1-3 represent the first example of true supramolecular isomerism within 3D 3-connected nets. Besides the 4.8.10 net for the tetragonal phase 1 (P4(2)/n, a= 13.470(2), c= 6.142(2)A), two novel 3-connected nets, 8(2)10-a and 6.10(2), were observed in the new tetragonal phase 2 (I42d, a= 14.0247(5), c= 5.2884(4)A) and orthorhombic phase 3 (Iba2, a= 8.0423(7), b= 11.5310(10), c= 17.3505(16)A), respectively. The three isomers also displayed distinct physical properties related to their different supramolecular structures.

Journal Article↗
PubMed2005

Hydrogen-bonded anionic rosette networks assembled with guanidinium and C3-symmetric oxoanion building blocks.

Two premeditated anionic rosette-layer architectures have been constructed using guanidinium and ubiquitous C3-symmetric oxoanions that carry unequal charges, employing bulky organic cations as interlayer templates. The undulate guanidinium-carbonate network occurs in 4[(C2H5)4N+].8[C(NH2)3+].3(CO3)2-.3(C2O4)2-.2H2O, in which the disordered (C2H5)4N+ guests are accommodated in pouches and channels within a complex three-dimensional hydrogen-bonded host framework. In [(C2H5)4N+]2.[C(NH2)3+].[1,3,5-C3H3(COO-)3].6H2O, ordered (C2H5)4N+ cations are sandwiched between planar guanidinium-trimesate host layers whose honeycomb cavities are tightly fitted with flattened-chair (H2O)6 clusters of symmetry 2.

Anions↗
PubMed2005

Well-resolved, new water morphologies obtained by modification of the hydrophilic/hydrophobic character and shapes of the supporting layers.

The planar coordination complexes [Ag2L2] (L = ophen or obpy, where Hophen = 1H-[1,10]phenanthrolin-2-one and Hobpy = 1H-[2,2']bipyridinyl-6-one) contain both hydrophilic and hydrophobic functional groups. Crystallization of these structurally related complexes in an aqueous medium gives [Ag2(ophen)2]2 x 6H2O (1), [Ag2(obpy)2]3 x 18H2O (2), and [Ag2(obpy)2]2 x 14.5H2O (3). Novel water morphologies are observed in these crystalline hydrates, similar 2D metal-organic layers in which the planar [Ag2L2] complexes as building blocks are stacked alternately together and provide hydrogen bond acceptor sites (O atoms) for anchoring 1D water chains or 2D water layers on their surfaces. In the wavelike metal-organic framework of 1, the wide hydrophobic region renders the formation of 1D water tapes containing four- and six-membered water rings, whereas more complex 2D water layers are sandwiched in 2 and 3, owing to the fact that the surfaces of the supporting layers are more hydrophilic than 1.

Journal Article↗
PubMed2005

Copper(I) 1,2,4-triazolates and related complexes: studies of the solvothermal ligand reactions, network topologies, and photoluminescence properties.

One-pot solvothermal treatments of organonitriles, ammonia, and Cu(II) salts yielded Cu(I) and 3,5-disubstituted 1,2,4-triazolates. The organic triazolate components were derived from copper-mediated oxidative cycloaddition of nitriles and ammonia, in which a key intermediate 1,3,5-triazapentadienate was isolated as [Cu(II)(4-pytap)(2)] (4-Hpytap = 2,4-di(4-pyridyl)-1,3,5-triazapentadiene) via controlled solvothermal conditions. This intermediate could also be synthesized by Ni(II)-mediated reactions; however, the final triazoles were obtained only when Cu(II) was employed. Therefore, the reaction mechanism of these reactions was elucidated as follows: nitrile was first attacked by ammonia to form the amidine, which further reacted with another nitrile or self-condensed to yield 1,3,5-triazapentadiene, which was coordinated to two Cu(II) ions in its deprotonated form. A two-electron oxidation of the 1,3,5-triazapentadienate mediated by two Cu(II) ions gave one triazolate and Cu(I) cations. Other in situ ligand reactions, such as C-C bond cleavage and hydrolysis, were also found for the nitriles under these solvothermal conditions. Another remarkable feature of these crystalline Cu(I) triazolates is their simple, typical 3- or 4-connected network topologies. The self-assembly of these nets is presumably controlled by steric hindrance, which is subsequently applied to the rational design of the close-packed 2D networks [Cu(I)(tz)](infinity) and [Ag(I)(tz)](infinity) (Htz = 1,2,4-triazole), as well as the porous 3D network [Cu(I)(etz)](infinity) (Hetz = 3,5-diethyl-1,2,4-triazole). The interesting photoluminescence properties of these coinage d(10) metal complexes were also investigated.

Journal Article↗
PubMed2005

Metallophilicity versus pi-pi interactions: ligand-unsupported argentophilicity/cuprophilicity in oligomers-of-dimers [M2L2]n (M=CuI or AgI, L=tridentate ligand).

To verify whether attractive metallophilic interactions exist in the dimer-of-dimers [Cu(2)(ophen)(2)](2) (Hophen=1H-[1,10]phenanthrolin-2-one) (1), we designed and synthesized a series of such [M(2)L(2)](2) structures by varying the d(10) metal and/or the ligand (M=Cu(I) or Ag(I), L=ophen or obpy; Hobpy=1H-[2,2']bipyridinyl-6-one), and have successfully obtained three dimers-of-dimers: [Ag(2)(ophen)(2)](2).6 H(2)O (2), [Cu(2)(obpy)(2)](2) (3), and [Ag(2)(obpy)(2)](2).4.5 H(2)O.0.5 DMF (4). X-ray analyses of these structures show that interdimer M-M separations in [Ag(2)-(ophen)(2)](2) (3.199 A) are remarkably shorter than those in [Cu(2)(ophen)(2)](2) (3.595 A). Shorter interdimer M-M separations are found in the structures of [M(2)(obpy)(2)](2) (2.986 and 2.993 A in [Cu(2)(obpy)(2)](2), 3.037 to 3.093 A in [Ag(2)(obpy)(2)](2)), in which the pi systems are smaller than in the complexes with the ophen ligand. Detailed structural comparison of these dimers-of-dimers indicates that the interdimer, face-to-face pi-pi interactions repulse rather than support the interdimer metal-metal attractive interactions. This study also yields qualitative comparison of the strengths between argentophilic, cuprophilic, and face-to-face pi-pi interactions. DFT calculations on the four dimers-of-dimers further support the above deduction. The structure of a trimer-of-dimers [Ag(2)(obpy)(2)](3) (Ag-Ag 3.171 to 3.274 A) is further evidence that the oligomerization of the [M(2)L(2)] molecules is favored by stronger metallophilic and weaker face-to-face pi-pi interactions.

Journal Article↗
PubMed2003

Syntheses, structures, photoluminescence, and theoretical studies of a novel class of d10 metal complexes of 1H-[1,10]phenanthrolin-2-one.

A novel asymmetric monosubstituted 1,10-phenanthroline, Hophen.0.5 H(2)O (1, Hophen=1H-[1,10]phenanthrolin-2-one), was generated by a facile route, and a novel class of crystalline, d(10)-metal, monomeric or oligomeric complexes of this ligand, namely [Hg(ophen)(2)].4 H(2)O.CH(2)Cl(2) (2), [Cd(3)Cl(ophen)(5)].1.5 H(2)O.2 CH(2)Cl(2) (3), and [Zn(4)O(ophen)(4)(OAc)(2)].4H(2)O.2 CH(2)Cl(2) (4), were obtained by means of liquid diffusion, and were characterized by X-ray crystallography and photoluminescence studies. Complex 1 exhibits a hydrogen-bonded dimeric structure, 2 is a neutral monomeric complex, 3 has a trinuclear structure with the ophen ligand acting as a bridge through the ketone groups, and 4 features a tetranuclear Zn(4)O core that is consolidated further by bridging ophen and acetate ligands. All the complexes display photoluminescent properties in the blue/green region. The photoluminescent mechanisms were investigated by means of molecular orbital calculations, which showed that the photoluminescent properties are ligand-based and can be tuned upon ligation to different metal ions.

Aldose-Ketose Isomerases↗
PubMed2003

A novel, highly electrical conducting, single-component molecular material: [Ag2(ophen)2] (Hophen = 1H-[1,10]phenanthrolin-2-one).

This communication describes a highly conducting, single-component molecular material [Ag2(ophen)2] (Hophen = 1H-[1,10]phenanthrolin-2-one) based on very strong off-set pi-pi stacking interactions with an unusually short ring-to-ring distance of ca. 3.15 A between adjacent molecules and silver(I)-pi interactions with the Ag...C contact of 3.082 A between adjacent molecules. The title compound, having a room-temperature conductivity of 14 S cm-1, is structurally different from both the known conducting single-component molecular materials of transition-metal complexes with sulfur-containing pi-delocalized dithiolene ligands and the known conducting multicomponent organosilver(I) materials.

Journal Article↗