Selective and Recyclable Congo Red Dye Adsorption by Spherical FeO Nanoparticles Functionalized with 1,2,4,5-Benzenetetracarboxylic Acid.

In this study, the new material FeO@BTCA has been synthesized by immobilization of 1,2,4,5-Benzenetetracarboxylic acid (BTCA) on the surface of FeO NPs, obtained by co-precipitation of FeCl.6HO and FeCl.4HO in the basic conditions.

Catalytic CO Fixation over a Robust Lactam-Functionalized Cu(II) Metal Organic Framework.

A porous, Cu(II)-metal organic framework () constituted of a rigid lactam functionalized ditopic ligand (HL) was synthesized at room temperature under slow evaporation conditions {HL = (5-(1-oxo-2,3-dihydro-1H-inden-2-yl)isophthalic acid)}. The single crystal X-ray structure revealed the formation of a 3D framework of with one-dimensional (1D) channels decorated with lactam groups and exposed metal centers in the crystallographic -axis. Interestingly, Cu(II) coordinated DMF molecules were eliminated from the Cu(II) metal center on activation of at a temperature of 150 °C under high vacuum to generate a solvent free framework with pores lined with unsaturated Lewis acidic Cu(II) ions, i.

Preparation of the Ru(CO)-pyridine-alcohol cluster and its use for the selective catalytic transformation of primary to secondary amines.

The synthesis of pyridine alcohol based ruthenium carbonyl clusters Ru3(hep)2(CO)8 (1), Ru3(hpp)2(CO)8 (2), and Ru3(bhmp-H)2(CO)8 (3) {hep-H = 2-(2-hydroxyethyl)pyridine, hpp-H = 2-(3-hydroxypropyl)pyridine and bhmp-H2 = 2,6-bis(hydroxymethyl)pyridine} has been carried out by the reaction of the corresponding pyridine-alcohol ligands with Ru3(CO)12. Clusters 1-3 have been characterized using elemental analysis, NMR, FT-IR, mass spectrometry and single-crystal X-ray structures. The clusters were explored for the selective catalytic transformation of primary amines into secondary amines using alcohols as the mono-alkylating agents via hydrogen transfer reactions.

Varying structural motifs in the salen based metal complexes of Co(ii), Ni(ii) and Cu(ii): synthesis, crystal structures, molecular dynamics and biological activities.

Herein, we report the structural and biological activities of a deprotonated Schiff base ligand (HL) {HL = 1,1'-(1E,1'E)-(2,4,6-trimethyl-1,3-phenylene)bis(azan-1-yl-1-ylidene)bis(methan-1-yl-1-ylidene)dinaphthalen-2-ol} towards Co(ii), Ni(ii) and Cu(ii) complexes obtained under different conditions. Four new metal complexes have been synthesized: isostructural dimers [Co(L)] (1)/[Cu(L)] (3), a monomer (ClNiHL)·(EtNH) (2) and a tetramer [Cu(L)] (4). The bioactivity of 1-3 has been investigated through molecular docking with DNA and various proteins, known to be involved in the proliferation of viral diseases or progression of cancer.

The development of fluorescence turn-on probe for Al(III) sensing and live cell nucleus-nucleoli staining.

The morphology of nucleus and nucleolus is powerful indicator of physiological and pathological conditions. The specific staining of nucleolus recently gained much attention due to the limited and expensive availability of the only existing stain "SYTO RNA-Select". Here, a new multifunctional salen type ligand (L) and its Al complex (1) are designed and synthesized.

Varying coordination modes of amide ligand in group 12 Hg(II) and Cd(II) complexes: synthesis, crystal structure and nonlinear optical properties.

Reactions of the amide ligand, H2L (H2L = N,N'-bis[2-(2-pyridyl)methyl]pyridine-2,6-dicarboxamide) with CdCl2 and Hg(CH3COO)2, in 1 : 1 ratio, at 298 K yield dimeric [Hg(L)]2 (1) and trimeric [Cd3(H2L)4Cl6] (2), respectively. In 1, the H2L is coordinated to Hg(II) via six N-atoms of central and terminal pyridines as well as of deprotonated amido groups, whereas the carbonyl groups remain free. However, in 2, the H2L is coordinated to Cd(II) through terminal pyridine N atoms and O atoms from carbonyl groups, whereas the nitrogen atoms of the central pyridine, two terminal pyridine and of all amido groups remain free.

Channel characteristics and planform dynamics in the Indian Terai, Sharda River.

The Sharda River creates and maintains the ecologically diverse remnant patches of rare Terai ecosystem in northern India. This study used repeat satellite imagery and geographic information system analysis to assess the planform dynamics along a 60 km length of the Sharda River between 1977 and 2001 to understand the altered dynamics and its plausible causes in this data-poor region. Analyses revealed that the Sharda River has undergone significant change corresponding to enhanced instability in terms of increased number of neck cut-offs and consistent occurrence of avulsions in subsequent shorter assessment periods.

Formation of a 1D-polymeric chain of Hg building blocks through C-C coupling under ambient conditions.

A novel C-C coupled 1D-polymeric chain (1) is obtained by reaction of HgCl2 and hmp-H (2-(2-hydroxymethyl pyridine)) (1 : 1) in MeOH at ambient temperature. However, a new class of μ-oxo and μ-chloro bridged polymers (2) has been obtained by altering the metal : ligand ratio to 1 : 2.

Biomimetic sensor for certain catecholamines employing copper(II) complex and silver nanoparticle modified glassy carbon paste electrode.

A dimeric Cu(II) complex [Cu(μ(2)-hep)(hep-H)](2)·2ClO(4) (1) containing bidentate (hep-H=2-(2-hydroxyethyl)pyridine) ligand was synthesized and characterized by single crystal X-ray diffraction studies. Each Cu-ion in 1 is in a distorted square pyramidal geometry. Further 1 along with silver nanoparticles (SNPs) have been used as modifier in the construction of a biomimetic sensor (1-SNP-GCPE) for determining certain catecholamines viz.

Molecular precursors for the preparation of homogenous zirconia-silica materials by hydrolytic sol-gel process in organic media. Crystal structures of [Zr{OSi(O(t)Bu)3}4(H2O)2]·2H2O and [Ti(O(t)Bu){OSi(O(t)Bu)3}3].

[Zr(OPr(i))(4)·Pr(i)OH] reacts with [HOSi(O(t)Bu)(3)] in anhydrous benzene in 1:1 and 1:2 molar ratios to afford alkoxy zirconosiloxane precursors of the types [Zr(OPr(i))(3){OSi(O(t)Bu)(3)}] (A) and [Zr(OPr(i))(2){OSi(O(t)Bu)(3)}(2)] (B), respectively. Further reactions of A or B with glycols in 1:1 molar ratio afforded six chemically modified precursors of the types [Zr(OPr(i))(OGO){OSi(O(t)Bu)(3)}] (1A-3A) and [Zr(OGO){OSi(O(t)Bu)(3)}(2)] (1B-3B), respectively [where G = (-CH(2)-)(2) (1A, 1B); (-CH(2)-)(3) (2A, 2B) and (-CH(2)CH(2)CH(CH(3)-)} (3A, 3B)]. The precursors A and B are viscous liquids, which solidify on ageing whereas the other products are all solids, soluble in common organic solvents.

One pot synthesis of maleimide and hydantoin by Fe(CO)5 catalyzed [2 + 2 + 1] co-cyclization of acetylene, isocyanate and CO.

In the presence of a catalytic amount of Fe(CO)(5), terminal acetylenes, isocyanates and CO undergo [2 + 2 + 1] cyclization to form substituted maleimides and hydantoins; when internal alkynes are used, exclusive maleimide formation is observed. While the maleimides can be obtained as the major products, in up to 90% yield, when the reaction is carried out in CO atmosphere, in absence of CO, the hydantoins are formed in up to 87% yield. Formation of maleimides has been shown to occur via the formation of a ferrole intermediate, whereas the hydantoins are proposed to form through successive insertion of isocyanate into the iron-acetylide bond.

Reversible single-crystal to single-crystal transformations in a Hg(II) derivative. 1D-polymeric chain <=>2D-networking as a function of temperature.

Reactions of HgX(2) (X = Cl(-), Br(-), l(-)) with the ligand hep-H (hep-H = 2-(2-hydroxyethyl)pyridine) in methanol at 298 K result in 1D-polymeric chains of [(X)Hg(mu-X)(2)(hep-H)](infinity), 1-3, respectively, where hep-H binds to the Hg(ii) ions in a monodentate fashion exclusively with the pyridine nitrogen donor and the suitably ortho-positioned -(CH(2))(2)OH group of hep-H remains pendant. The packing diagrams of 1-3 exhibit extensive intramolecular and intermolecular hydrogen bonding interactions leading to hydrogen bonded 2D network arrangement in each case. Though the single crystal of either 2 (X = Br) or 3 (X = I) loses crystallinity upon heating, the single crystal of 1 selectively transforms to a 2D-polymeric network, 4 on heating at 383 K for 1.

Biomimetic sensor for certain phenols employing a copper(II) complex.

A new dimeric Cu(II) complex [Cu(mu(2)-hep)(hep-H)](2).2PF(6) (1) containing a bidentate (hep-H = 2-(2-hydroxyethyl)pyridine) ligand was synthesized and characterized by single crystal X-ray diffraction studies. Each Cu ion in 1 is in a distorted square pyramidal geometry.

Single-crystal to single-crystal transformations in discrete hydrated dimeric copper complexes.

The single crystals of discrete hydrated [(OAc)Cu(mu-hep)(2)Cu(OAc)].2H(2)O (.2H(2)O) and [(OAc)Cu(mu-hep)(2) Cu(O(n)Pr)].

Occurrence of phthalic acid esters in Gomti River Sediment, India.

Phthalic acid esters (PAEs) are well-known ubiquitous environmental pollutants and used as plasticizers for the manufacturing of plastic products. During this exploratory study, an attempt has been made to determine the concentration and distribution of five prominent PAEs, viz. di-methyl phthalate (DMP), di-ethyl phthalate (DEP), di-butyl phthalate (DBP), di-(2-ethylhexyl) phthalate (DEHP), and di-octyl phthalate (DOP) in the sediment samples of Gomti River collected from 30 different locations.

Vapor-diffusion-mediated single crystal-to-single crystal transformation of a discrete dimeric copper(II) complex to a discrete tetrameric copper(II) complex.

The symmetric dimeric complex [Cu(mu(2)-hep)(TFA)(H(2)O)](2) (1) has been synthesized from 2-(2-hydroxyethyl)pyridine (hep-H), trifluoroacetic acid (TFA-H), and copper acetate in a 95:5 (v/v) MeOH-H(2)O mixture at 298 K. Each Cu(II) ion in 1 is linked with two mu(2)-alcoholic oxygen atoms and one pyridine nitrogen atom of hep, and the other two coordination sites are occupied by the oxygen donors of TFA and H(2)O. At room temperature, the blue single crystals of 1 transform to the green single crystals of a tetrameric complex, [Cu(4)(mu(3)-hep)(2)(mu(2)-hep)(2)(mu(2)-TFA)(2)(TFA)(2)] (2), in presence of alcoholic vapor.

Reduction of nitrite to NO in an organised triphasic medium by platinum carbonyl clusters and redox active dyes as electron carriers.

Artificial electron donors such as leuco methylene blue and leuco safranin O reduce nitrite ion to nitric oxide. The reaction is effected in a U-tube where nitrite ion and dye in two aqueous layers are separated by a layer of dichloromethane (a close model for a biological liquid membrane) that contains the platinum carbonyl cluster ([Bu(4)N]2[Pt12(CO)24], Chini cluster). On passing dihydrogen an electron transfer chain involving dihydrogen, the dye, the clusters and the nitrite ion is initiated.

Novel Approach to Mixed Group 15/16 Element Ligands-Formation of Unusual Trichalcogenophosphonato Ligands in Mixed Fe/Cr Clusters.

Trithiophosphonato and triselenophosphonato ligands containing mixed Fe/Cr clusters have been synthesized from the reaction of [Fe (CO) (μ -Y) ] (Y=S or Se) with [CpCr(CO) (η -P ] in the presence of trimethylamine oxide. This novel approach leads to new clusters containing the first examples of P(S)S and P(Se)Se ligands in complexed forms.