Search

With the introduction of 2,2′-bipyridine (2,2′-bipy) agent, two new zinc coordination polymers (CPs), {[Zn6(HL-H)4(2,2′-bipy)4]·¼H2O}n1 and {[Zn3(HL-H)2(H2O)4]·6H2O}n2, have been hydrothermally obtained derived from diphosphonic acid, 1-hydroxy-2-(3-pyridyl)ethylidene-1,1-diphosphonic acid (H5L = (H4C5N)CH2C(OH)(PO3H2)2, HL-H = (H4C5N–H)CH2C(OH)(PO3)2), and determined by single-crystal X-ray diffractions, elemental analysis, IR, powder X-ray diffractions (PXRD). The single-crystal X-ray diffractions reveal that compound 1 owns a novel 1-D fishbone-like inorganic chain structure built from binuclear building blocks [Zn2(O–P–O)2]n via [ZnO4]n tetrahedron linkers. It is the first example that N-heterlcyclic amine 2,2′-bipy is used as the second ligand to construct the compound 1 with the diphosphonic acid ligand H5L. Both hydrogen bonding and π–π stacking interactions further extend the 1-D chain to the 3-D supramolecular network. Compound 2 exhibits a 2-D reticulate layer structure containing 4-, 8- and 16-membered rings created from 1-D ladder-like inorganic chain, and the organic pyridine rings in the structure point to voids defined by the 16-membered rings. Moreover, the room-temperature fluorescence measurements show that both the compounds display two fluorescent emissions centered at 379, 424 nm for 1 and 380, 424 nm for 2, respectively, caused by intraligand π*–π emission state of organic pyridine ring (λex = 235 nm). With the introduction of 2,2′-bipyridine (2,2′-bipy) agent, two new Zn(II)-phosphonate CPs, 1-D {[Zn6(HL-H)4(2,2′-bipy)4]·¼H2O}n1 and 2-D {[Zn3(HL-H)2(H2O)4]·6H2O}n2 (H5L = (H4C5N)CH2C(OH)(PO3H2)2, HL-H = (H4C5N–H)CH2C(OH)(PO3)2), have been hydrothermally obtained and characterized. The thermal stabilities and fluorescent properties of them have been investigated. [ABSTRACT FROM AUTHOR]

The example of Co(II)-N-heterocyclic complex based on 1-hydroxyethylidenediphosphonic acid (H5L = CH3C(OH)(PO3H2)2), namely [Co2(H3L)2(2,2′-bipy)2] 1, has been solvothermally isolated using the second ligand 2,2'-bipyridine (2,2'-bipy) and characterized by powder X-ray diffraction (PXRD), elemental analysis, IR, and thermal gravimetric analyses. The single-crystal X-ray diffractions show that complex 1 possesses a 0-D structure built from binuclear unit [Co2(O–P–O)2] by μ2-(O–P–O) bridge. Then, H-bonding and π–π stacking interactions further expand this 0-D structure into a 3-D supramolecular framework. Fluorescent measurements reveal that the maximum emission peak is centered at 421.5 nm, mainly deriving from intraligand π*–π transition state of the second ligand 2,2'-bipy (λem = 419.5 nm, λex = 235 nm). Magnetism data indicate that 1 exhibits ferromagnetic behavior within binuclear Co(II) unit via μ2-(O–P–O) bridge in syn-anti mode. [ABSTRACT FROM AUTHOR]

By introducing the second ligand 1,10-phenanthroline (phen), three low-dimensional examples of Cd/Zn diphosphonates based on 1-hydroxyethylidenediphosphonic acid (HL = CHC(OH)(POH)), [Cd(HL)(phen)(HO)] 1, {[Zn(HL)(phen)]·2HO} 2 and [Zn(HL)(phen)]·(HOCHCHOH) 3, have been hydro- or solvo-thermally obtained and characterized by powder X-ray diffraction (PXRD), elemental analysis, IR, TG-SDTA. The single-crystal X-ray diffractions show that both compounds 1 and 3 display zero-dimensional structures built from binuclear units [M(OPO)] (M = Cd/Zn) via a double O-P-O bridge, and compound 2 possesses one-dimensional fish-bone inorganic chain structure with three types of coordination modes of Zn(II) ions. Then H-bond or/and π- π stacking interactions further expand the low-dimensional structures into the three-dimensional supramolecular frameworks. Fluorescent measurements reveal that the maximum emission peaks (371.5, 391.5 nm for 2 and 376.5, 392.5 nm for 3) of 2-3 have a significant increase in intensity compared to those of the phen ligand ( λ = 362.5, 379 nm, λ = 335 nm), which are mainly caused by intraligand π*- π emission state of the phen ligand. The results of electrochemical measurements indicate the donor ability of 1- 3 has gone up, compared with the ligands (HL and phen). Graphical Abstract: Three examples of CdZn diphosphonates have been hydro- or solvo-thermally obtained. Two Zn(II) diphosphonates with 1,10-phenanthroline indicate a significant increase in intensity of fluorescence. The results of electrochemical measurements indicate the donor ability of Cd/Zn diphosphonates increase, compared with the ligands HL and phen.[InlineMediaObject not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Two CdII-containing coordination polymers based on a multidentate N-donor ligand and two structure-related dicarboxylate ions, namely, [Cd2(3,4′-tmbpt)( o-bdc)2] ·2H2O ( 1) and [Cd2(3,4′-tmbpt)2( p-bdc)2] ·6.5H2O ( 2) [3,4′-tmbpt = 1-((1 H-1,2,4-triazol-1-yl)methyl)-3-(4-pyridyl)-5-(3-pyridyl)-1,2,4-triazole, o-H2bdc = 1,2-benzenedicarboxylic acid, and p-H2bdc = 1,4-benzenedicarboxylic acid], were prepared under hydrothermal conditions. The structures of the two compounds were determined by single-crystal X-ray diffraction analysis and further characterized by infrared spectra (IR) and elemental analysis. Compound 1 is a 3D framework containing infinite Cd-O chains. Compound 2 displays a 2D → 2D interdigitated architecture. The effect of the dicarboxylate ions on the structures of the compounds was discussed. Moreover, the optical bandgaps and photoluminescent properties of the compounds were investigated. [ABSTRACT FROM AUTHOR]

Two coordination polymers [Cu(phen)(L)(HO)] ( 1) and [Ni(phen)(L)(HO)]·0.5HO ( 2), where phen = 1,10-phenanthroline and HL = 5,5′-(ethane-1,2-diyl)-bis(oxy)diisophthalic acid, have been synthesized under hydrothermal conditions. In complex 1, the L anions and the phen ligands connect the Cu(II) ions to form a layer. The phen ligands act as arms and thread into the adjacent layer, forming a 2D → 3D polythreaded architecture. In complex 2, the L anions and the phen ligands link the Ni(II) ions to form a layer. Further, the adjacent layers interdigitate each other through intermolecular π − π interactions to generate a 2D → 3D interdigitated architecture. Their structures have been determined by single-crystal X-ray diffraction analyses and further characterized by infrared spectra (IR) and elemental analyses. The thermal properties and optical band gaps of complexes 1 and 2 have also been investigated. Graphical Abstract: Two interesting 2D → 3D polythreaded and interdigitated coordination polymers based on the flexible 5,5′ -(ethane-1,2-diyl)-bis(oxy)diisophthalic acid have been successfully synthesized, where the thermal properties and optical band gaps of the complexes have also been investigated. [Figure not available: see fulltext.]. [ABSTRACT FROM AUTHOR]

Five inorganic–organic hybrid compounds have been prepared under hydrothermal conditions and characterized by single-crystal X-ray diffraction analyses, infrared spectra, elemental analyses, powder X-ray diffraction, and thermogravimetric analyses. In1, each 2,2ʹ-tmbpt ligand links two Cu(II) ions to generate a highly undulated chain. The chains are further bridged by [SiW12O40]4‒anions to form a layer. Compound2exhibits a 3-D (3,4,5)-connected framework with large channels, in which [SiW12O40]4‒anions are tetradentate linkages. In3, each 2,4ʹ-tmbpt links three Cu(II) ions to form 2-D layers, which are further linked by [SiW12O40]4‒to yield a 3-D (3,4)-connected framework. In4, each 4,4ʹ-tmbpt connects three Cu(II) ions to generate 1-D double chains. In5, [PW12O40]3‒link Cu(II) ions to generate 1-D chains. Compounds1‒5exhibit photocatalytic activities for degradation of methylene blue and rhodamine B. Five inorganic–organic hybrid compounds have been synthesized, and the photocatalytic properties of the compounds have also been studied. [ABSTRACT FROM PUBLISHER]

By introducing the second ligand 2,2'-bipy, a new copper(II) diphosphonate [Cu(HL)(2,2′-bipy)] 1 (HL = 1-hydroxyethylidenediphosphonate, 2,2′-bipy = 2,2′-bipyrimidine) has been hydrothermally synthesized and characterized by powder X-ray diffraction, elemental analysis, IR and TG-DTA. The single-crystal X-ray diffractions show that compound 1 possess a three-dimensional supramolecular structure, built from 1D chain via a single-bridge O-P-O in syn-anti fashion based on mononuclear unit [CuON]. UV-vis spectra and the nature of electron transfer of 1 are investigated, and the experimental results are in agreement with the quantum chemistry calculation using the B3LYP/6-31G* method. Fluorescent measurements reveal that two emission peaks of 1 centered at 382.5 and 424.5 nm are mainly caused by intraligand π*- π emission state of the second ligands (375, 429.5 nm, λ = 235 nm). Results of electrochemical studies (CV) indicate a higher donor ability of 1. [ABSTRACT FROM AUTHOR]

Two examples of Co(II)- N -heterocyclic coordination polymers based on 1-hydroxyethylidenediphosphonic acid (H 5 L = CH 3 C(OH)(PO 3 H 2 ) 2 ), namely 0.5(H 3 NCH 2 CH 2 NH 3 )·[Co 6 (Cl 2 )(H 3 L) 2 (H 2 L)(HL)(2,2′-bipy) 6 ] 1 and 2(NH 4 )·[Co 3 (HL) 2 (H 2 O) 2 (phen) 2 ]·2(H 2 O) 2, have been solvothermally obtained by introducing the second ligands 2,2′-bipyridine/1,10-phenanthroline (2,2′-bipy/phen) and characterized by powder X-ray diffraction (PXRD), elemental analysis, IR, TG-DSC. The single-crystal X-ray diffractions show that compound 1 possesses a 0-D structure with hexa-nuclear cluster [Co 6 (O–P–O) 8 ] built through single/double O–P–O bridges and compound 2 displays a 1-D ladder-like chain structure with magnetic topology building blocks [Co 4 (O–P–O) 4 ] n . Then H-bonding and π – π stacking interactions further expand the two low-dimensional structures into three-dimensional supramolecular frameworks. Fluorescent measurements reveal that both the maximum emission peaks of 1–2 are centered at 423 nm, mainly deriving from intraligand π *– π transition state of N -heterocyclic ligand 2,2′-bipy/phen, respectively. Magnetism data indicate that 1 exhibits antiferromagnetic behavior within hexa-nuclear Co(II) clusters, while 2 shows weak ferromagnetic interactions in 1-D topology Co(II)-chain, showing promising potential as magnetic materials. [ABSTRACT FROM AUTHOR]

Two new supramolecular architectures, [Co(dafo)(HO)]·1,5-nds 1 and [Co(phen)(HO)(1,5-nds)] 2 (1,5-nds = 1,5-naphthalenedisulfonate; dafo = 4,5-diazafluoren-9-one; phen = 1,10-phenanthroline), were synthesized and characterized by element analysis, IR, XRD, TG-DSC and single-crystal X-ray diffraction. Compounds 1 and 2 exhibit 2D and 3D supramolecular structures via O-H∙∙∙O hydrogen bond interactions and π- π interactions, respectively. The compound 1 represents the first example of the Co(II)-1,5-nds-dafo system, in which the [Co(dafo)(HO)] chains and the counter anions 1,5-nds appear alternately. In addition, luminescent properties of 1 and 2 were discussed. The emission band at 422 nm of 1 is attributed to intraligand transitions. 2 shows two emission bands centered at 420 nm which may be originated from the intraligand emission from the phen ligand and at 459 nm assigned to the combined interaction of intraligand π* → π transitions of the phen ligand and ligand-to-metal charge-transfer (LMCT) transitions ( λ = 254 nm). [ABSTRACT FROM AUTHOR]

A novel coordination polymer, namely, [Cd 7 (4,4′-tmbpt) 3 ( d -cam) 6 (OH) 2 ]·8.25H 2 O ( 1 ), where 4,4′-tmbpt = 1-((1 H -1,2,4-triazol-1-yl)methyl)-3,5-bis(4-pyridyl)-1,2,4-triazole, and d -H 2 cam = d -camphoric acid, has been synthesized under hydrothermal condition. Compound 1 exhibits a three-dimensional homochiral (3,8,9)-connected framework, which is a rare example of coordination polymer with homochiral highly connected structure based on the chiral source of d -H 2 cam. The structure of the compound was determined by single-crystal X-ray diffraction analysis and further characterized by infrared spectrum (IR), elemental analysis and UV–Vis spectrum. Moreover, the optical band gap and photoluminescent property of the compound have been investigated. [ABSTRACT FROM AUTHOR]