Indian Journal of Chemistry

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Sect. A: Inorganic, Bio-inorganic, Physical, Theoretical & Analytical

 

VOLUME 46A

NUMBER 4

April 2007

 

CONTENTS

 

 

561

 

Theoretical investigation of the reactivity in the C-H bond activation of CH4 by CoS+ in the gas phase

 

 

 

 Xiao-Yan Yang, Yong-Cheng Wang*,
Zhi-Yuan Geng & Ze-Yu Liu

 

 

 

The reaction of CoS+ with CH4 has been studied on both quintet and triplet potential energy surfaces at the UB3LYP/6-311+G* level. The lowest-energy path involves a formal 1, 2-addition of H3C-H across the Co+-S bond to generate a CH3CoSH+ insertion intermediate. The crossing points have been found by means of single-point computations as a function of the structural change along the intrinsic reaction coordinate.

 

 

568

 

Spectral and thermal properties of hydrazinium metal(II) ethylenediaminetetra­acetates: Crystal structure of a novel seven coordinated manganese(II) complex

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

L Vikram & B N Sivasankar*

 

 

 

Some new hydrazinium metal(II) ethylenediaminetetraacetates, (N2H5)2[M(EDTA)] and (N2H5)3[M(EDTA)(H2O)](NO3)(H2O) (where M = Co, Ni, Cu or Zn) have been prepared and characterized by analytical, spectral and thermal techniques.

 

Text Box:  

 

576

 

2-(Naphthyl-a-azo)imidazole complexes of manganese(II). Single crystal X-ray structure of [Mn(a-NaiEt)2(NCS)2] (a-NaiEt = 1-ethyl-2-(naphthyl-a-azo)imidazole)

 

 

 

 

 

 

 

 

 

 

P Bhunia, K K Sarker, C–N Lin, T–H Lu &
C Sinha*

 

 

 

Azido/thiocyanato-manganese(II)-naphthylazoimidazole comp- lexes have been characterized. Single crystal X-ray diffraction data of [Mn(a-NaiEt)2(NCS)2] (a-NaiEt = 1-ethyl-2-(naphthyl-a-azo)imidazole) confirm the tetrahedrally coordinated MnN4 structure of the complex.

 

 

 

 

 

 

 

 

 

 

 

 

582

 

Spectral and thermal characterization of newly synthesized arylazo benzimidazole mercury(II) complexes

 

 

 

 

Sawsan S Haggag

 

 

 

Mercury(II) complexes with arylazo benzimidazole have been synthesized and characterized.

 

 

 

589

 

Kinetic study on the effects of inert salts on
pH- independent hydrolysis of phthalimide in mixed nonionic-ionic and ionic-ionic micelles

 

  

 

M Niyaz Khan* & Emran Ismail

 

 

 

Pseudo first-order rate constants, kobs, for pH-independent hydrolysis of phthalimide in the presence of constant [mixed micelles] and varying values of [MX], where MX represents inert salts, viz., C6H5CO2Na, C6H5OCH2CO2Na and NaBr, follow the empirical relationship: kobs = {k0 + q K [MX]}/{1 + K [MX]} where q and K are empirical constants and k0 = kobs at [MX] = 0.

 

Notes

 

595

 

Acid doped polyaniline nanofibers synthesized by interfacial polymerization

 

 

  

Bitao Su*, Yongchun Tong, Jie Bai, Ziqiang Lei,
Ke Wang, Hongmei Mu & Na Dong

 

 

 

Acid-doped polyaniline (acetic, phosphoric, hydrochloric and perchloric acids) nanofibers have been synthesized by interfacial polymerization and characterized. The diameters of the nanofibers (30-50 nm) increase with the increase in acid strength.
The electrical conductivity of nanofibers varies in the
order: HAC-PANI<H3PO4-PANI<HClO4-PANI< HCl-PANI.

 

 

600

 

Mixed ligand complexes of Co(II) containing
5-bromosalicylaldehyde and β-diketones, hydroxyaryl aldehydes or ketones

 

 

 

  

 

R N Prasad*, Kirti Mohan Sharma &
Anjali Agrawal

 

 

 

Mixed ligand complexes of the type [Co(5-Brsal)(L)(H2O)2] (where HL = salicylaldehyde, 2-hydroxyacetophenone,
2-hydroxypropiophenone, 2-hydroxybenzophenone, 2-hydroxy-1-naphthaldehyde, pentane-2,4-dione, 1-phenylbutane-1,3-dione or 1,3-diphenylpropane-1,3-dione) have been synthesized.

 

 

605

 

Synthesis and characterization of some new homodinuclear alkoxo derivatives of bismuth(III) containing dialkyldithiophosphate ligands

 

 

 

 

 

 

  

 

 

 

Pankaj Kumar Sharma & Yashpal Singh*

 

 

 

 

 

 

610

 

Kinetic studies of substitution on [(H2O)(tap)2RuORu(tap)2(H2O)]2+ ion by
DL-penicillamine at physiological pH

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

  

 

 

 

Alak Kumar Ghosh

 

 

 

At pH 7.4, the reaction of DL-penicillamine with the title complex is a two-step process and the second step is ligand independent.

 

 

615

 

Thermodynamics of dilution of inositol in aqueous sodium chloride solution at 298.15 K

 

 

 

 

De Zhi Sun*, Wen Qing Zheng & Xiu Kui Qu

 

 

 

The enthalpies of dilution of inositol in aqueous sodium chloride solution at various concentrations have been determined by isothermal flow-mixed microcalorimetry at 298.15 K. Results show that enthalpic pairwise interaction coefficients of inositol are negative in aqueous sodium chloride solution and become less negative with increase in concentration of sodium chloride.

 

 

620

 

Sorption studies on clay for the removal of phenol and p-nitrophenol from aqueous solution

 

 

 

Preeti Sagar Nayak* & B K Singh

 

 

 

Sorption of phenol and p-nitrophenol (PNP) from aqueous solution has been investigated using was clay sorbent. Sorption of phenol onto clay  were calculated and it is seen fitteds the Langmuir model and followsed pseudo second-order kinetics. and rate constant k was calculated.

 

624

 

Separation of oxoanions from mixed aqueous solvents using strongly basic anion exchanger Amberlite IRA-400 in nitrate form

 

 

 

 

 

Radha Tomar*, Pankaj Sharma &
Vandana Kushwah

 

 

 

The strongly basic anion exchanger, Amberlite IRA-400 in nitrate form, has been studied for separation of oxoanions, viz., chromate, molybdate and tungstate, from aqueous solutions of methanol, ethanol and isopropanol. Exchange of anions increases with increase in temperature and alcoholic content in partly nonaqueous medium. Selectivity data for chromate/nitrate exchange in mixed methanolic solvents also indicates remarkable effect of particle size and quantity of the resin on the exchange.

 

 

628

 

Solid phase extractive preconcentration of CoCo(II) and MnMn(II) from environmental and biological samples using 2-hydroxy-acetophenone-3-thiosemicarbazone functionalized Amberlite XAD-2 and determination by ICPAES

 

  

 

S. Satyaveni, K. Pratap, G. P. Chandra Rao and&
 K. Seshaiah*

 

 

 

A method for solid phase extraction of the trace metals namely, CoCo(II) and MnMn(II), using Amberlite XAD-2 functionalized with a new chelating ligand, 2-hydroxyacetophenone-3-thiosemicarbazone has been developed. The detection limits were are 0.82 µg g-1 for CoCo(II) and 0.64 µg g-1 for MnMn(II). The chelating resin could can be reused for more than 20 cycles of sorption-desorption without any significant change (<1.5 %) in sorption of metal ions (<1.5%).

 

 

Authors for correspondence are indicated by (*)

 

 

 

 

Indian Journal of Chemistry

Vol. 46A, April 2007, pp. 561-567

 

Theoretical investigation of the reactivity in the C-H bond activation of CH4 by CoS+ in the gas phase

Xiao-Yan Yang, Yong-Cheng Wang*, Zhi-Yuan Geng & Ze-Yu Liu

Received 13 July 2006; revised 13 February 2007

The reaction of CoS+ with CH4 has been studied on both quintet and triplet potential energy surfaces at the UB3LYP/6-311+G* level. All the products are formed in endothermic processes. The lowest energy path involves a formal 1,2-addition of H3C-H across the Co+-S bond to generate a CH3CoSH+ insertion intermediate. This bond activation step involves spin inversion from the quintet to the triplet surface en route to the products. The crossing points have been found by means of single-point computations as a function of the structural change along the intrinsic reaction coordinate.

Indian Journal of Chemistry

Vol. 46, April 2007, pp. 568-575

 

Spectral and thermal properties of hydrazinium metal(II) ethylenediaminetetraacetates: Crystal structure of a novel seven coordinated manganese(II) complex

 

L Vikram & B N Sivasankar*

Received 22 September 2006; revised 19 February 2007

Some new hydrazinium metal(II) ethylenediaminetetraacetates, (N2H5)2[M(EDTA)] where M = Co, Ni, Cu or Zn and (N2H5)3[M(EDTA)(H2O)](NO3)(H2O) have been prepared and characterized by analytical, spectral and thermal techniques. The conductivity and infrared spectral data acquired for these complexes suggest the ionic nature of hydrazinium cations. Magnetic moments and electronic spectra indicate the octahedral geometry around the metal ions with EDTA serving as a hexadentate ligand. The crystal structure of hydrazinium aquoethylenediaminetetraacetatomanganate nitrate monohydrate has been determined from single crystal X–ray analysis. The crystallographic data for this compound are: orthombic, space group P21/c with a = 8.934(5), b = 12.712 (5), c = 19.514 (5) Ĺ with Z = 4 and R = 0.0248. The manganese ion is seven coordinated with four carboxylate oxygen atoms and two nitrogen atoms from EDTA occupying six coordination sites while the seventh site is occupied by a water molecule. These complexes undergo multi–step degradation to give the respective metal oxides as the residue.

IPC Code: Int. Cl.8 C07F13/00

Indian Journal of Chemistry

Vol. 46A, April 2007, pp. 576-581

 

2-(Naphthyl-a-azo)imidazole complexes of manganese(II). Single crystal X-ray structure of [Mn(a-NaiEt)2(NCS)2] (a-NaiEt = 1-ethyl-2-(naphthyl-a-azo)imidazole)

P Bhunia, K K Sarker, C–N Lin, T–H Lu & C Sinha*

Received 16 October 2006; revised 4 February 2007

Azido/thiocyanato-manganese(II)-naphthylazoimidazole complexes, [Mn(a-NaiR)2(X)2] (a-NaiEt = 1-alkyl-2-(naphthyl-a-azo)imidazole; X = N3-, NCS-), have been characterized. Microanalytical, spectral (FT-IR, UV-vis) and magnetic (bulk and EPR) data have been used to establish the molecular and electronic structure of the complexes. The single crystal X-ray diffraction measurements of [Mn(a-NaiEt)2(NCS)2] (a-NaiEt = 1-ethyl-2-(naphthyl-a-azo)imidazole)  confirm the tetrahedrally coordinated MnN4 structure of the complex. Cyclic voltammetry exhibits Mn(III)/Mn(II) couple along with azo reductions.

IPC Code: Int. Cl.8   C07F13/00

 

Indian Journal of Chemistry

Vol. 46A, April 2007, pp. 582-588

 

Spectral and thermal characterization of newly synthesized arylazo benzimidazole mercury(II) complexes

Sawsan S Haggag

Received 1 September 2006; revised 16 February 2007

Mercury(II) complexes of benzimidazole and its derivatives, (viz., benzimidazole (Benz.) (I); 1H-2-(naphthyl α-azo) benzimidazole (α-NaBenz.) (II); and 1H-2-(arylazo)benzimidazole (III)) of the type HaaBZR, where R=H (a), -CH3 (b), -NO2 (c) and–OH (d) have been synthesized and characterized by elemental analysis, infrared, mass and 1H NMR spectra. The stoichiometric ratios for the Hg(II) complexes have been identified as (1:1), (1:2) or (2:1) with the contribution of coordinated water and chloride in complex formation. The probable structures for the mercury(II) complexes are also proposed. The results from mass spectral studies are in agreement with the TGA of the fragmentation and mass losses.

IPC Code: Int. Cl.8 C07F3/10

 

Indian Journal of Chemistry

Vol. 46A, April 2007, pp. 589-594

 

Kinetic study on the effects of inert salts on pH-independent hydrolysis of phthalimide in mixed nonionic-ionic and ionic-ionic micelles

M Niyaz Khan* & Emran Ismail

Received 21 June 2006; revised 8 February 2007

Pseudo first-order rate constants, kobs, for pH-independent hydrolysis of phthalimide in the presence of constant [mixed micelles] and varying values of [MX], where MX represents inert salts C6H5CO2Na, C6H5OCH2CO2Na and NaBr, follow the empirical relationship: kobs = {k0 + q K [MX]}/{1 + K [MX]} where q and K are empirical constants and k0 = kobs at [MX] = 0.

IPC Code:  Int. Cl.8  C07B41/00

 

Indian Journal of Chemistry

Vol. 46A, April 2007, pp. 595-599

 

Acid doped polyaniline nanofibers synthesized by interfacial polymerization

Bitao Su*, Yongchun Tong, Jie Bai, Ziqiang Lei, Ke Wang, Hongmei Mu & Na Dong

Received 17 August 2006; revised 8 February 2007

Acid-doped polyaniline (PANI) nanofibers have been successfully synthesized by interfacial polymerization and characterized by TEM, FT-IR and UV-vis spectra and thermal analysis. The TEM results show that the type of dopant acid: acetic, phosphoric, hydrochloric and perchloric acids, and the concentrations of aniline monomer and acid affect the morphology and diameter of the nanofibers. The diameters of the nanofibers are in the range of 30-50 nm, which increase with the increase in acid strength. The electrical conductivity of nanofibers varies in the order: HAC-PANI<H3PO4-PANI<HClO4-PANI< HCl-PANI, which is closely related to the acid type and the size of its negative ion. Thermal stability of acid-doped PANI is different from that of EB PANI, which is attributed to the strong interaction between PANI and doped acid.

IPC Code: Int. Cl.8 B82B; D01F6/60; D01F8/12; H01B1/12

Indian Journal of Chemistry

Vol. 46A, April 2007, pp. 600-604

 

Mixed ligand complexes of Co(II) containing 5-bromosalicylaldehyde and β-diketones, hydroxyaryl aldehydes or ketones

R N Prasad*, Kirti Mohan Sharma & Anjali Agrawal

Received 28 February 2006; revised 21 February 2007

Mixed ligand complexes of the type [Co(5-Brsal)(L)(H2O)2] (where HL = salicylaldehyde, 2-hydroxyacetophenone,2-hydroxypropiophenone, 2-hydroxybenzophenone, 2-hydroxy-1-naphthaldehyde, pentane-2,4-dione, 1-phenylbutane-1,3-dione or 1,3-diphenylpropane-1,3-dione) have been synthesized by the reactions of cobalt(II) nitrate with two different carbonyl compounds in 1:1:1 molar ratios. The resulting complexes have been characterized by elemental analyses, conductances, magnetic moments, IR, electronic, ESR and FAB mass spectra.

IPC Code: Int. Cl.8 C07F15/06

Indian Journal of Chemistry

Vol. 46A, April. 2007, pp. 605-609

 

Synthesis and characterization of some new homodinuclear alkoxo derivatives of bismuth(III) containing dialkyldithiophophate ligands

Pankaj Kumar Sharma & Yashpal Singh*

Received 8 September 2006; revised 19 February 2007

Reactions of sodium tetraisopropoxobismuthate(III), NaBi(OPri)4 (prepared in situ) with chlorobis (dialkyldithiophosphato)bismuth(III) compounds, [(RO)2P(S)S]2BiCl in 1:1 molar ratio in refluxing benzene solution yield a new series of homodinuclear alkoxide derivatives of bismuth(III) of the type [(RO)2P(S)S]2Bi(m-OPri)2Bi(OPri)2 [where, R = Me(1); Et(2); Pri(3); Prn(4); and Bun(5)]. All the derivatives in this series are non-volatile, moisture-sensitive, dark-brown colored, viscous liquids, which are soluble in common organic solvents. The compounds have been characterized by elemental analyses and molecular weight measurements. Probable structure for the derivatives is proposed on the basis of IR and NMR (1H, 13C and 31P) spectral studies.

IPC Code: Int. Cl.8 C07F9/94

 

Indian Journal of Chemistry

Vol. 46A, April 2007, pp. 610-614

 

Kinetic studies of substitution on [(H2O)(tap)2RuORu(tap)2(H2O)]2+ ion by dl-penicillamine at physiological pH

 

Alak Kumar Ghosh

Received 10 July 2006; revised 5 February 2007

The reaction of dl-penicillamine with the title complex has been studied spectrophotometrically in aqueous solution as a function of concentrations of the substrate complex and ligand, pH and temperature. The reactivity of different donor centers [i.e., (N), (N,O) and (O,O)] have been compared. At pH 7.4 the reaction is a two-step process. Unlike other systems studied with the same substrate, the second step in the present case is ligand independent, ascribed to the lower difference between the two steps (k1 = 1.78´10-3 s-1and k2 = 0.67´10-4 s-1 respectively at 50°C) in comparison to the other systems studied earlier (k1~10-3s-1 and k2~10-5s-1). An associative interchange mechanism is proposed for both the steps. The activation parameters (DH1ą = 19.2 ± 1 kJ mol-1, DS1ą = -239 ± 3 JK-1 mol-1; DH2ą = 65.6 ± 5.8 kJ mol-1 and DS2ą = -123 ± 17 JK-1 mol-1) support the proposition. The activation parameters have been compared with other systems studied earlier.

Indian Journal of Chemistry

Vol. 46A, April 2007, pp. 615-619

 

Thermodynamics of dilution of inositol in aqueous sodium chloride solution at 298.15 K

De Zhi Sun*, Wen Qing Zheng & Xiu Kui Qu

Received 6 June 2006; revised 8 March 2007

The enthalpies of dilution of inositol in aqueous sodium chloride solution at various concentrations have been determined by isothermal flow-mixed microcalorimetry at 298.15 K. The homogeneous enthalpic coefficients have been calculated over a large range of concentration of aqueous sodium chloride solution according to the excess enthalpy concept. The results show that enthalpic pairwise interaction coefficients (h2) of inositol are negative in aqueous sodium chloride solution and become less negative with increase in concentration of sodium chloride.

Indian Journal of Chemistry

Vol. 46A, April 2007, pp. 620-623

 

Sorption studies on clay for the removal of phenol and p-nitrophenol from aqueous solution

Preeti Sagar Nayak* & B K Singh

Received 6 March 2006; revised 7 March 2007

Sorption of phenol and p-nitrophenol from aqueous solution has been investigated using clay sorbent. The effect of particle size of sorbent, pH, phenol concentration and temperature on sorption capacity has been studied by batch experiments. Langmuir adsorption isotherm constants show that the sorption data for phenols onto clay fits well in this model. The sorption of phenols studied follows pseudo second-order kinetics. This study shows that clay can be used as an efficient sorbent material for the sorption of phenols from aqueous solution.

IPC Code: Int. Cl.8 B01D15/00; B01J20/12

 

Indian Journal of Chemistry

Vol. 46A, April 2007, pp. 624-627

 

Separation of oxoanions from mixed aqueous solvents using strongly basic anion exchanger Amberlite IRA-400 in nitrate form

Radha Tomar*, Pankaj Sharma & Vandana Kushwah

Received 23 May 2006; revised 10 February 2007

Batch technique has been employed to evaluate the ability of strongly basic anion exchanger Amberlite IRA-400 in nitrate form to separate oxoanions, viz., chromate, molybdate and tungstate from mixed aqueous solvents such as aqueous methanol, aqueous ethanol and aqueous isopropanol. Conclusions have been drawn regarding the variation of selectivity coefficient with change in solvent composition and rise in temperature. Thermodynamics of ion exchange has also been studied. The data indicate that strongly basic anion exchanger Amberlite IRA-400 in nitrate form has got very good potential for separation of these oxoanions and exchange of anions increases with increase in temperature and alcoholic content in partly non-aqueous medium. The selectivity data for chromate/nitrate exchange in mixed methanolic solvents also suggests that there is a remarkable effect of particle size and quantity of the resin on exchange.

IPC Code: Int. Cl.8 B01J41/00

Indian Journal of Chemistry

Vol. 46A, April 2007, pp. 628-632

 

Solid phase extractive preconcentration of Co(II) and Mn(II) from environmental and biological samples using 2-hydroxy-acetophenone-3-thiosemicarbazone functionalized Amberlite XAD-2 and determination by ICPAES

 

S Satyaveni, K Pratap, G P Chandra Rao & K Seshaiah*

Received 25 July 2006; revised 15 February 2007

A method for solid phase extraction of the trace metals, Co(II) and Mn(II), using Amberlite XAD-2 functionalized with a new chelating ligand, 2-hydroxyacetophenone-3-thiosemicarbazone (Amberlite XAD-2-HAPTSC) has been developed. The optimum experimental conditions for the quantitative sorption of two metals, pH, effect of flow rate, concentration of eluent, sorption capacity, kinetics of sorption and the effect of diverse ions on the sorption of analytes have been investigated. At pH 5.0 the quantitative sorption of two metals onto functionalized resin is observed and complete elution of metals from resin has been achieved with 2.0 mol l-1 nitric acid. The detection limits are 0.82 µg g-1 for Co(II) and 0.64 µg g-1 for Mn(II). The sorption half time (t1/2) was found to be 7.5 min for Co(II) and 6.5 min for Mn(II), while the sorption capacities in mg/g are 3.2 for Co(II) and 4.1 for Mn(II). The chelating resin can be reused for more than 20 cycles of sorption-desorption without any significant change in sorption of metal ions (<1.5%). The accuracy of the proposed procedure has been evaluated by comparing the results with ICP-MS. The proposed method has been applied for the determination of trace metals in river water and leafy vegetable samples collected from different sources near Tirupati.

IPC Code: Int. Cl.8 G01N30/00