Indian Journal of Chemistry

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

 

VOLUME 41A

NUMBER 11

NOVEMBER 2002

CONTENTS

Papers

 

2209

 

Electrocyclic ring opening of 3,4-dihydro-1,2,4-triazine: An AM1 study of kinetic control exerted by a nitrogen lone pair

 

 

 

Pankaj K Pal, Shubhamoy Chowdhury &

Dipankar Datta*

 

 

 

2212

 

Thiocyanate induced chemiluminescence in dioxane based liquid scintillation fluids

 

 

 

 

Neela Sen Gupta, Maitreyi Bhattacharjee* &

Esahak Ali

 

 

 

Thiocyanate ion produces strong delayed chemiluminescence in dioxane containing peroxides. The luminescence is observed as a pulse in the presence of a scintillator(2,5 diphenyloxazole), but not in the presence of toluene or 1,4-bis(5-phenyl-2-oxazolyl)benzene alone. The pulse amplitude and delay time is dependent on thiocyanate concentration.

 

2216

 

Adsorption of fluids on hard wall : Application of inhomogeneous pair correlation function

 

 

 

 

 

 

A Guha* & Ashish Mukherjee

 

 

The density profile of the fluid near the hard wall is obtained from the direct correlation function defined by Ornstein - Zernike equation with Percus Yevick analytical solution. In the case of outside the hard sphere core, the mean spherical model approximation (MSMA) has been used to calculate the direct correlation function. The adsorption of a model Lennard -Jones fluid near a hard wall has been calculated.

 

2223

 

Synthesis and characterization of AlPO4-n molecular sieves from hexamethyleneimine template

 

 

 

 

N Venkatathri

 

 

 

The aluminophosphates, AlPO4-5, AlPO4-16, AlPO4-22, AlPO4-31, SAPO-35 and AlPO4-L, have been synthesized using hexamethyleneimine template and characterized. Results show that Al and P are in equimolar composition. The synthesized samples are highly crystalline with the morphology changing with structure.

Nitroxide radical

 

2231

 

Electrochemical oxidation and reduction of nitroxides : A cyclic voltammetric and simulation study

 

 

 

K Chabita (Saha) & P C Mandal*

 

 

 

 

 

2238

 

Preparation and characterisation of Zr, Ti and Zr-Ti mixed oxide pillared montmorillonite and their catalytic activity towards nitration of chlorobenzene

 

 

D Das, H K Mishra, K M Parida* & A K Dalai

 

 

 

Zr, Ti and Zr-Ti mixed oxide pillared montmorillonite have been prepared by standard method and their specific surface area, total acidity, and weight loss have been calculated. The total number of acid sites (mmol/g) are highest for 300°C calcined samples and follow the order: Zr-Ti PILC > ZrPILC > TiPILC.

 

 

2244

 

Synthesis, characterisation and benzylation activity of vanadia impregnated iron pillared montmorillonite

 

 

Rahna K Shamsudeen, K Nisha &

S Sugunan*

 

 

 

Iron pillared montmorillonite has been synthesised and wet impregnated with vanadia of different vanadia composition and characterised. Lewis acidic sites of these catalysts are responsible for the benzylation of toluene when the benzylating agent is benzyl chloride while Brönsted acidic sites are responsible when the reagent is benzyl alcohol.

 

 

2251

 

Catalysis by some metal oxides modified with phosphate ions

 

 

S Sugunan*, H Suja, C S Deepa,

K Sreejarani & M V Ouseph

 

 

 

Surface acidity of phosphate modified La2O3, CeO2 and SnO2 has been estimated by titrimetric method.. Mixed oxides of tin and lanthanum have also been prepared and subjected to phosphate modification. The catalytic activity for benzylation and esterification reactions has also been investigated.

 

2256

 

Effect of solvent on the reaction of coordination complexes. Part 26— Kinetics of solvolysis of trans-(chloro)bis (ethylene-diamine) (glycinato-O)cobalt(III) in methanol + water and propan-2-ol + water: delineation of preferential solvation

 

 

Prafulla K Das & Anadi C Dash*

 

 

 

The solvolysis of trans-(chloro)bis (ethylenediamine) (glycinato-O)cobalt(III) has been studied in methanol + water and propan-2-ol + water at 50.0 ± 0.1oC. The product, (glycinato-N,-O)bis(ethylenediamine) cobalt(III) species has resulted via the formation of trans-(aqua)(glycinato-O) bis (ethylenediamine)cobalt(III) intermediate.

 

2260

 

Synthesis and characterization of nicotinamide coordinated metal carbonyl complexes

 

 

 

 

 

 

 

 

D Jesudurai & S Vancheesan*

 

 

 

Notes

 

2268

 

Excess volumes, viscosities and compressibilities of binary mixtures consisting of propan-1-ol, butan-1-ol and pentan-1-ol with 1,2-dibromoethane at different temperatures

 

 

T Satyanarayana Rao, N Veeraiah &
C Rambabu*

 

 

 

The density, viscosity and ultrasonic velocity in binary mixtures of propan-1-ol, butan-1-ol and pentan-1-ol with 1,2-dibromoethane have been determined at different temperatures. Using these parameters, the excess volume, excess viscosity, excess compressibility, intermolecular free length and Grunberg and Nissan parameters have been calculated.

 

 

2274

 

Organic silica ligated to palladium (0) complex: A highly active and stereoselective catalyst for Heck reaction

 

S F Zhao, R X Zhou, Y F Yang ( X M Zheng*

 

 

 

2277

 

Synthesis of nanostructure LaMnO3 and LaCoO3 catalysts and their catalytic activity in oxidation reaction

 

Min Chen* & Xiao-Ming Zheng

 

 

 

Nanostructured perovskite-type oxides, LaMnO3 and LaCoO3 have been prepared by three different methods and characterized. On the basis of the results on CO oxidation reaction and TPR, the activity has been related to the size of the nanostructured perovskite-type ABO3 crystal.

 

2282

 

Synthesis and characterization of ionic heterobimetallic complexes of Ni(II), Cu(II), Zn(II) and Cd(II) ions containing nitrogen and sulphur donors

 

M K Singh*, R Laskar & A Das

 

 

 

2285

 

Synthesis, spectra and redox properties of Ru(II)carbonyl Schiff base complexes

 

 

 

 

R Ramesh* & G Venkatachalam

 

 

 

 

2288

 

Synthesis and characterisation of some hetero- cyclic derivatives containing aluminium(III) atoms in five- and six-coordination states: Reactions of bis(b-diketonato)-aluminium(III)-di-m-isopropoxo-di-isopropoxoaluminium(III) with o-aminobenzoic acid

 

Shweta Nagar, Rakesh Bohra* &

Ram C Mehrotra

 

 

 

 

2291

 

Studies on binuclear complexes of N(1)-salicylidene–N(2)-t(3)-methyl-r(2),c(6)-diphe-nylpiperidin-4-one azine

 

 

 

A Manimekalai* & R Mahendhiran

 

 

 

2296

 

Mixed metal clusters of iron and cobalt from carbonyl iron dichloro-phenylphosphine complexes with cyclopentadienyl cobaltdi-carbonyl

 

 

 

Rajib Lal De** & Kamales Maiti

 

 

 

 

2300

 

Alternative production and separation method of 111In by heavy ion activation of silver

 

 

 

 

Dalia Nayak, Susanta Lahiri* &

A Ramaswami

 

 

 

Heavy ion activation of natural silver foil with 48 MeV 7Li results in the formation of carrier-free 109-111Sn along with 109-111In radionuclides in the matrix. The carrier-free indium radionuclides have been separated from the bulk target matrix silver by liquid-liquid extraction as well as supported liquid membrane method using Aliquat-336 as liquid anion exchanger.

 

 

2303

 

Kinetic photometric determination of trace amounts of palladium (II) based on its catalytic effect on the reduction of safranin with hypophosphite

 

 

 

A Jabbari, M Barzegar, A Rahmani &

M F Mousavi*

 

 

A new kinetic method for the determination of trace amounts of palladium (II) based on its heterogeneous catalytic effect on the reduction reaction of safranin by hypophosphite has been described. The influence of reaction variables such as safranin and hypophosphite concentrations, ionic strength, and pH have been examined. The procedure has been applied successfully to the determination of Pd(II) in real samples.

 

 

2306

 

A spectroscopic study of charge-transfer complexes of aniline and N-alkylanilines with nitromethane

 

 

 

 

S Muzaffar Ali Andrabi

 

 

 

Formation of charge-transfer complexes of aniline,
N-methylaniline, N,N-dimethylaniline and N,N-diethylaniline with nitromethane (NM) in carbon tetrachloride solution has been investigated by UV-vis spectrophotometry and 1HNMR spectrometry. The stabilities of these complexes vary in the order: aniline-NM > N-methylaniline-NM > N,N-dimethylaniline-NM > N,N-diethylaniline-NM.

 

 

2310

 

Preconcentration with membrane cell and adsorptive cathodic stripping voltammetric determination of aniline in air

 

 

Zheng-Qi Zhang* & Hong Zhang

 

 

Aniline in air has been preconcentrated in a membrane cell and its content determined using adsorptive cathodic stripping voltammetry.

 

2315

 

Spectrophotometric determination of trace amounts of selenium (IV) by catalytic kinetic method

 

 

 

Shan Jinhuan*, Ding Liang, Wang Li,

Shen Shigang & Sun Hanwen

 

 

 

A spectrophotometric method for the determination of selenium(IV) is described, based on the selenium(IV)-catalyzed oxidation of methyl blue with KBrO3 in nitric acid medium. The method has been used to determine Se(IV) in Chinese herbal drugs.

 

 

 

2318

 

Ion exchange kinetics of alkaline earth metals on acrylamide zirconium(IV) phosphate cation exchanger

 

 

 

K G Varshney*, Vandana Jain &

Namrta Tayal

 

 

 

The kinetics of Mg(II), Ca(II), Sr(II) and Ba(II) exchange with H(I) on acrylamide zirconium(IV) phosphate has been studied applying the Nernst-Planck equation. The rate of exchange is found to be particle diffusion controlled at a metal ion concentration ≥ 0.01M in aqueous medium.

Authors for correspondence are indicated by (*)



 

 

 

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2209-2211

 

Electrocyclic ring opening of  3,4-dihydro-1,2,4-triazine: An AM1 study of kinetic control exerted by a nitrogen lone pair

Pankaj K. Pal, Shubhamoy Chowdhury & Dipankar Datta*

 

    AM1 calculations on the title reaction show that it is endothermic and proceeds thermally via two paths leading to two different isomers of the acyclic product. The path along which the lone pair of the N involved in the breaking C-N bond rotates inward has an energy barrier 5.1 kcal mol-1 lower than the one where the N lone pair rotates outward. The kinetically preferred path yields the energetically higher isomer of H2C=N-N=C(H)-C(H)=NH.

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2212-2215

 

 

Thiocyanate induced chemiluminescence in dioxane based liquid scintillation fluids

Neela Sen Gupta, Maitreyi Bhattacharjee* & Esahak Ali

        Dioxane  based cocktails are often used in liquid scintillation counting for water soluble biological samples. Phosphorescence is a problem with such cocktails and strong chemiluminescence has also been reported in the presence of a cationic detergent. It has been found that thiocyanate ion produces strong delayed chemiluminescence in dioxane containing peroxides. The luminescence is observed as a pulse in the presence of a scintillator(2,5 diphenyloxazole,PPO), but not in the presence of toluene or 1,4-bis(5-phenyl-2-oxazolyl)benzene(POPOP) alone. The pulse amplitude and delay time is dependent on thiocyanate concentration. In practice, the observed pulse intensity in a beta counter may be few thousand CPM with cocktails prepared with fresh dioxane to a few lakh CPM in aged cocktails.

 

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2216-2222

 

Adsorption of fluids on hard wall : Application of inhomogeneous
pair correlation function
A Guha*  &  Ashish Mukherjee

The local density of non-uniform fluids is important in understanding fluid behaviours in contact with the planar walls or slit like pore. The density profile of the fluid near the hard wall is obtained starting from the direct correlation function defined by Ornstein - Zernike equation with Percus Yevick analytical solution. The bridge function, which is useful to obtain the cavity function or radial distribution function, has been calculated. In the case of outside the hard sphere core, the mean spherical model approximation (MSMA) has been used to calculate the direct correlation function. The adsorption of a model Lennard -Jones fluid near a hard wall has been calculated. The results obtained for the generalized adsorption and agree well with the standard results.

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2223-2230

 

Synthesis and characterization of AlPO4-n molecular sieves from hexamethyleneimine template

 

N  Venkatathri

 

 

Aluminophosphates AlPO4-5, AlPO4-16, AlPO4-22, AlPO4-31, SAPO-35 and AlPO4-L have been synthesized using hexamethyleneimine template, by a procedure different  from the standard one.  Gel composition Al2O3: P2O5: 1.16HEM: 45H2O at 24h, 473K are  the standard reaction conditions for synthesis of AlPO4-5.  To  this, addition of excess template (1.35M)  leads to AlPO4-22.  Changing the aluminium source from catapal – B to aluminium isopropoxide gives AlPO4-16.  Aging for 8 h at room temperature with nonaqueous gel and stirring leads to AlPO4-31.  Addition of 0.3M SiO2 to non-aqueous AlPO gel gives SAPO-35.  The aluminophosphates have been characterized by elemental analysis, XRD, SEM, FT-IR, TG/DTA, and 13C MAS NMR techniques.  Elemental analysis shows that Al and P are in equal molar composition.  XRD analysis shows that the synthesized samples are highly crystalline.  SEM shows the morphology change with structure.  TG/DTA analysis reveals the presence of maximum five stage elimination of templates.  Carbon and nitrogen analysis gives the number of templates present in a unitcell of the molecular sieves.  13C NMR analysis shows the interaction of template with structure of the framework.

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2231-2237

 

 

Electrochemical oxidation and reduction of nitroxides : A cyclic voltammetric and simulation study

 

K Chabita (Saha)  & P C Mandal*

 

 

The oxidation and reduction of the nitroxides namely, Tempo (2,2,6,6- tetramethyl piperidine-N-oxyl), Tempol( 4-hydroxy 2,2,6,6 tetramethyl-piperidine-N-oxyl), TEMPO-NH2 or Tempamine (4-amino 2,2,6,6 tetramethyl-piperidine-N-oxyl) 3-carbamoyl proxyl and 4-methyl sulphonyloxy-Tempo have been followed by cyclic voltametry in aqueous medium at pH 6.8. The E1/2 values for the oxidation of these nitroxides to oxoammonium cation and then back to parent compound were found to be in the range of 0.85 to 1.0 V vs NHE. The diffusion coefficients (Dox) are of the order of 105 cm2/s and are dependent on the size of the molecule. The process is reversible, with a small amount undergoing chemical reaction after charge transfer. The rate constants for the forward chemical reaction after oxidation (kf) are of the order of 103 s-1. It has been observed that kf is the highest for NH2Tempo where the reversibility of the reaction is the lowest. In the negative potentials, where the reduction of nitroxides to hydroxylamines takes place irreversible waves have been  observed. The reduction process of the above nitroxides when studied in methanol and acetonitrile also shows irreversibility. Since the reduction process of these nitroxides shows poor reversibility, methods like Condecon (a computer software) has been used to calculate E1/2 values and other parameters like (Do) and (ana). This method has been found very effective for obtaining reduction potentials of nitroxides in aqueous solutions.
 

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2238-2243

Preparation, characterisation of Zr, Ti and Zr-Ti mixed oxide pillared
montmorillonite and their catalytic activity towards nitration of chlorobenzene

D Das, H K Mishra, K M Parida* & A K Dalai

 

Zr, Ti and Zr-Ti mixed oxide pillared montmorillonite (PILCs) have been prepared by standard method and their specific surface area, total acidity, and weight loss have been calculated. The mixed oxide pillared clays retain highest surface area even when calcined at 500°C. The total number of acid sites (mmol/g) are highest for 300°C calcined samples and follow the order Zr-Ti PILC > ZrPILC > TiPILC. Mononitration reaction is carried out using all the pillared montmorillonites calcined at different temperatures. The yield of mononitrochlorobenzene from chlorobenzene with different catalysts also follow the same order and no metaproduct was detected for this reaction. All samples show appreciably high paraselectivity i.e. close to 85%.

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2244-2250

 

Synthesis, characterisation and benzylation activity of vanadia impregnated iron pillared montmorillonite

 

 

Rahna K. Shamsudeen, K. Nisha &S. Sugunan*

 

Iron pillared montmorillonite has been synthesised and it is then wet impregnated with vanadia with different vanadia composition. These catalysts are characterised using conventional techniques such as XRD analysis, FTIR analysis, and surface area and pore volume measurements. Acidity is measured using spectrophotometric monitoring of adsorption of perylene, thermogravimetric desorption of 2,6 dimethylpyridine and temperature programmed desorption of ammonia. Activity studies are done in the liquid phase. It has been concluded that Lewis acidic sites are responsible for the benzylation of toluene when the benzylating agent is benzyl chloride while Brönsted acidic sites are responsible when the reagent is benzyl alcohol.

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2251-2255

 

Catalysis by some metal oxides modified with phosphate ions

S Sugunan, H Suja, C S Deepa, K Sreejarani & M V Ouseph

 
 

Surface acidity of phosphate modified La2O3, CeO2 and SnO2 has been estimated by titrimetric method using Hammett indicators. Mixed oxides of tin and lanthanum have  also  been prepared and subjected to phosphate modification. Surface characterization of the samples has been  carried out using XRD, surface area, thermal analysis and IR spectroscopy. Phosphate content in the samples has  been chemically estimated. The catalytic activity for benzylation and esterification reactions has also  been investigated.

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2256-2259

 

Effect of solvent on the reaction of coordination complexes. Part 26#— Kinetics of solvolysis of trans-(chloro)bis(ethylenediamine)(glycinato-O)cobalt(III) in methanol + water and propan-2-ol + water: delineation of preferential solvation.

 

Prafulla K Das & Anadi C Dash*

 

The solvolysis of trans-(chloro)bis(ethylenediamine)(glycinato-O)cobalt(III) has been studied in methanol + water and propan-2-ol + water at 50.0 ± 0.1oC. The product, (glycinato-N,-O)bis(ethylenediamine)cobalt(III) species has resulted via the formation of trans-(aqua)(glycinato-O) bis (ethylenediamine)cobalt(III) intermediate. The rate constant for chloride release obeys first order kinetics and decreases with the increase of the mol fraction of the co-solvent (Xorg) ; the  dependencies  of  log ks with  102/DS ( Ds is the bulk dielectric constant), Xorg and the solvent ionizing power (Y) have all been nonlinear and co-solvent specific. The variation of rate constant  with Xorg can be interpreted satisfactorily  on a preferential solvation model proposed earlier.  The dependence of pK (the dissociation of the protonated amine function) on XPriOH  also conforms to the results on the rate constants that hydrophobic interaction controls the rate and equilibria. However, there is no change in the intimate  mechanism of the chloride substitution at cobalt(III) centre.

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2260-2267

 

Synthesis and characterization of nicotinamide coordinated metal carbonyl complexes

D Jesudurai & S Vancheesan*

 

Three new nicotinamide coordinated group VI B metal carbonyl complexes  fac-[M(CO)3(nicotinamide)3] (M = Cr, Mo, and W; 4, 5, and 6) (nicotinamide = 3-H2NOCC5H4N) have been synthesized. Reaction of the ‘in situ’ generated complex precursors fac-[M(CO)3(CH3CN)3] (M = Cr, Mo, and W; 1, 2, and 3) with three equivalents of nicotinamide in methanol at room temperature give nicotinamide coordinated metal carbonyl complexes 4, 5, and 6 in good yields. The complexes exhibit two bands corresponding to n(CºO) of metal carbonyl groups and n(C=O) of nicotinamide ligands. All the complexes exhibit a very strong stretching band corresponding to n(C=O) of coordinated nicotinamide ligands at 1684 (Cr, 4); 1669 (Mo, 5); and 1683 cm-1 (W, 6). The occurrence of single n(C=O) band suggests the coordination of three nicotinamide molecules that are arranged cis to each other and representing a C3v configuration of ligands around the metal atom in the facial geometry of the complexes. The 1H NMR spectra of the complexes shows signals at four different chemical shift regions, corresponding to the four protons on the pyridine ring of the nicotinamide ligand. The calculated integral value of each signal is present in the ratio 1:1:2:2. The powder X-ray diffractogram of the complexes exhibit similar pattern suggesting the similar arrangements of atoms in the crystal lattice and geometry.

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2268-2273

 

Excess volumes, viscosities and compressibilities of binary mixtures consisting of propan-1-ol, butan-1-ol and pentan-1-ol with 1,2-dibromoethane at different temperatures

T Satyanarayana Rao, N Veeraiah & C  Rambabu*

 

The density, viscosity and ultrasonic velocity in binary mixtures of propan-1-ol, butan-1-ol and pentan-1-ol with 1,2-dibromoethane have been determined at different temperatures from 298.15 to 313.15 K over the whole composition range. Using these parameters the excess volume (VE), excess viscosity (hE), excess compressibility (KsE), inter molecular free length (Lf) and Grunberg and Nissan parameter d have been evaluated. The values of (VE) for propan-1-ol + 1,2-dibromoethane system and butan-1-ol+ 1,2-dibromoethane system are found to be negative at all temperatures whereas for pentan-1-ol +1,2-dibromoethane the (VE) values are observed to be negative at low concentration of pentan-1-ol (up to 0.1 molefraction). However, this parameter is found to be positive above 0.1 mole fraction. hE values are observed to be negative for all the systems over the entire composition range. The observed value of excess adiabatic compressibility is found to be negative for propan-1-ol + 1,2-dibromoethane and butan-1-ol + 1,2-dibromoethane and positive for pentan-1-ol + 1,2-dibromoethane. Analysis of these parameters indicates that there are inter molecular interactions among components of the binary mixtures that lead to the possible hydrogen bond formation (of the type Br…H-O) between unlike molecules.

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2274-2276

 

Organic silica ligated to palladium (0) complex: A highly active and stereoselective catalyst for Heck reaction

S F Zhao, R X Zhou, Y F Yang  & X M Zheng*

 

Organic silica ligated to palladium(0) complex has been prepared from polyγ-cyanopropyl triethoxysilane and fumed silica, followed by treatment with palladium chloride in ethanol and then the reduction with KBH4 in ethanol. This catalyst is highly active and stereoselective for Heck reaction at 90 °C or 100 °C.

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2277-2281

 

Synthesis of nanostructure LaMnO3 and LaCoO3 catalysts and their catalytic activity in oxidation reaction

Min Chen* & Xiao-Ming Zheng

 

Nanostructured perovskite-type oxides, LaMnO3 and LaCoO3  have been prepared by three different methods, such as, the sol-gel method, the precipitation method, and the amorphous-complexometry method. X-ray diffraction, transmission electron microscopy , and BET surface area measurements have been used to characterize the catalysts. The spectroscopy measurements reveal that there are differences in the formation of the perovskite-type oxides by the different methods. The reduction properties of these two systems have been investigated by using H2-TPR. The shape and temperature of TPR peaks depend on the nature of the particle size of the catalyst and the preparation method. On the basis of the results on CO oxidation reaction and TPR, the activity of CO oxidation has been related to the size of the nanostructured perovskite-type ABO3 crystal.

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2282-2284

 

Synthesis and characterization of  ionic heterobimetallic complexes of  Ni(II), Cu(II), Zn(II) and Cd(II) ions  containing nitrogen and sulphur donors

 

M K Singh*, R Laskar & A Das

 

       A number of new ionic heterobimetallic complexes of copper(II), nickel(II), zinc(II) and cadmium(II) ions of the compositions, [Cu (N-N)2 ][ M (S-S)2 ] [  N-N =  ethylenediamine ( en ),  trimethylenediamine( tn ); M = Ni(II), Zn(II) or Cd(II); S-S = 1,1-dicyanoethylene-2,2-dithiolate, (CN)2C=CS22-, (i-MNT2-)] have been synthesized by the reaction of nitrogen coordinated metal cations and sulphur coordinated metal anions in aqueous/ aqueous-acetone medium and characterized. Complexed metal cations   and   complexed   metal   anions   required   for   the   synthesis   have    been    prepared in  situ  by  the known    literature    procedures. The molar conductance data reveal that the complexes have 1:1 electrolytic nature in DMSO solution. Magnetic and electronic spectral studies suggest four-coordinated metal ions in these complexes. Infrared spectral studies suggest bidentate chelating behaviour of ethylendiamine, trimethylenediamine and 1,1-dicyanoethylene-2,2-dithiolate ion in their complexes.

 

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2285-2287

 

Synthesis, spectra and redox properties of Ru(II)carbonyl Schiff base complexes

 

R Ramesh* & G Venkatachalam

 

 

          The reaction of bidentate Schiff bases (LL’) viz H-salampy, H-salmet or H-salchx with [RuHCl(CO)(B)(PPh3)2] (where B = triphenylphosphine, pyridine, piperidine and morpholine) yield Ru(II) complexes of the type [RuCl(CO)(B)(PPh3)(LL′)]. All the complexes have been characterized by elemental analysis, spectral  (IR, electronic and  1H NMR) and electrochemical data.  An octahedral structure has been tentatively proposed for all these complexes.

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2288-2290

 

Synthesis and characterisation of some heterocyclic derivatives containing aluminium(III) atoms in five- and six-coordination states: Reactions of bis(b-diketonato)-aluminium(III)-di-m-isopropoxo-di-isopropoxoaluminium(III) with o-aminobenzoic acid

Shweta Nagar, Rakesh Bohra* & Ram C Mehrotra

 

Reactions of bis(β-diketonato)aluminium(III)-di-μ-isopropoxo-di-isopropoxo-aluminium(III), [(CH3COCHCOR)2Al(μ-OPri)2 Al(OPri)2] with o-aminobenzoic acid,(HOOCC6H4NH2) in 1:1 and 1:2 molar ratios in refluxing anhydrous benzene yield binuclear complexes of the types,[(CH3COCHCOR)2Al(μ-OPri)2Al (OOCC6H4NH2)(OPri)] and [(CH3COCHCOR)2Al(μ-OPri)2 Al(OOCC6H4NH2)2)] (where R = -CH3, -OC2H5 and -C6H5 ), respectively . All these binuclear complexes have been characterised by elemental analyses, molecular weight measurements, IR and NMR (1H,13C and 27Al) spectral studies .

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2291-2295

 

Studies on binuclear complexes of N(1)-salicylidene–N(2)-t(3)-methyl-r(2),c(6)-diphenylpiperidin-4-one azine

A Manimekalai* & R Mahendhiran

A novel heterocyclic ligand, N(1)-salicylidene-N(2)-t(3)-methyl-r(2),c(6)-diphenylpiperidin-4-one azine (SMDPA) and its complexes with Ni(II) [Ni(NO3)2,NiCl2 and Ni(ClO4)2],Co(II) and Cu(II) have been prepared and characterized by elemental analyses, magnetic susceptibility measurements, spectral and thermal analyses. The spectral data reveal that the ligand (HL) acts as a uni-negative bidentate ligand and the metal:ligand stoichiometry to be 2:2 with all the metal ions. The X-ray (powder) diffraction study of Ni(NO3)2- SMDPA complex shows that the complex crystallises in triclinic lattice.

 

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2296-2299

Mixed metal clusters of iron and cobalt from carbonyl iron dichloro-phenylphosphine complexes with cyclopentadienyl cobaltdicarbonyl

 

Rajib Lal De* & Kamales Maiti

The reaction of CpCo(CO)2 with the monoiron carbonyl phosphine complexes, Fe(CO)4PPhCl2 and the two diiron carbonyl phosphine complexes, Fe2(CO)6(PPhCl)2, Fe2(CO)6(PPhCl2) have been studied which yields the heterometallic phosphorus bridged cluster molecules (CpCo)2Fe(CO)4PPh(1) and (CpCo)2Fe(CO)5PPh(2); (CpCo)2Fe(CO)3(PPh)2(4) and (CpCo)2Fe2(CO)5(PPh)2(5); CpCoFe2(CO)7PPh(6) and (CpCo)2Fe2(CO)5(PPh)2(7) respectively. A homometallic complex (CpCo)4(PPh)2(3) is also obtained as a side product from the reaction with Fe(CO)4PPhCl2 only. All the products have been characterised by the analytical data and IR, 1H-NMR and mass spectra.

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2300-2302

 

Alternative production and separation method of 111In by

heavy ion activation of silver

 

Dalia Nayak, Susanta Lahiri* & A Ramaswami

 

Heavy ion activation of natural silver foil with 48 MeV 7Li results in the formation of carrier-free 109-111Sn along with their corresponding decay products, 109-111In radionuclides, in the matrix. The carrier-free indium radionuclides have been separated from the bulk target matrix silver by employing liquid-liquid extraction as well as supported liquid membrane method using Aliquat-336 as liquid anion exchanger.

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2303-2305

 

Kinetic photometric determination of trace amounts of palladium (II) based on its catalytic effect on the reduction of safranin with hypophosphite

 

A Jabbari, M Barzegar, A Rahmani & M F Mousavi*

 

A new kinetic method for the determination of trace amounts of palladium (II) based on its heterogeneous catalytic effect on the reduction reaction of safranin (SAF) by hypophosphite (HP) has been described. The reaction is monitored at 516 nm and the time elapsed, Dt, for the absorbance to decrease by 1.5 absorbance units from its initial value is recorded (variable time method). The influence of reaction variables such as safranin and hypophosphite concentrations, ionic strength, and pH have been examined. The range of linearity is 0.03-2.22 ppm palladium(II) at temperature of 25°C (n=7, r=0.9998). The detection limit is 0.02 ppm. The relative standard deviation of the developed method is 1.8% (for 10 replicate determinations of 1.11 ppm of Pd(II)). The effect of interferences from other metal ions and some anions is also studied. The procedure has been applied successfully to the determination of Pd(II) in real samples.

 

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2306-2309

 

A spectroscopic study of charge-transfer complexes of aniline and N-alkylanilines with nitromethane

 

S.Muzaffar Ali Andrabi

 

 

 

Formation of yellow coloured charge-transfer complexes of aniline, N-methylaniline, N,N-dimethylaniline and N,N-diethylaniline with nitromethane (NM) in carbon tetrachloride solution has been investigated by UV-vis spectrophotometry and 1HNMR spectrometry. The lCT of the resulting 1:1 molecular complexes were isolated. The molar absorptivities and association constants were determined. The stabilities of these complexes vary in the order: aniline-NM > N-methylaniline-NM > N,N-dimethylaniline-NM > N,N-diethylaniline-NM. The study shows that hydrogen bonding contributes significantly to the stabilities of the complexes of aniline and N-methylaniline.

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2310-2314

 

Preconcentration with membrane cell and adsorptive cathodic stripping voltammetric determination of aniline in air

 

Zheng-Qi Zhang & Hong Zhang

 

Aniline in air is preconcentrated in a membrane cell and its content has been determined using adsorptive cathodic stripping voltammetry. Aniline in air samples is preconcentrated in a membrane cell using 3.0 mol/L HCl solution, to form a diazoate with NaNO2, which is reduced to phenyl hydrazine in presence of Na2SO3. The hydrazine reacts with formaldehyde to form phenylhydrazone, which is adsorbed at the mercury electrode and yields a sensitive adsorptive cathodic stripping voltammetric wave. The peak currents are linearly proportional to the concentration of aniline over the range 6.0´10-9 - 5.0´10-5 mol/L. The detection limit is 2.0´10-9 mol/L.

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2315-2317

 

Spectrophotometric determination of trace amounts of selenium (IV)

by catalytic kinetic method

 

Shan Jinhuan*, Ding Liang, Wang Li, Shen Shigang & Sun Hanwen1

 

A spectrophotometric method for the determination of selenium(IV) is described, based on the selenium(IV)-catalyzed oxidation of methyl blue with KBrO3 in nitric acid medium. As the redox reaction proceeds, the blue colour of the dye is decolorized. LogA0/A shows a good linear relationship with the amount of selenium. The detection range of the method is 0-5mg dm-3 with sensitivity of 0.3527mg dm-3. The system is selective as most of the cations, viz, copper, potassium, iron, etc. can be tolerated during the determination of   Se (IV). The method has been used to determine Se(IV) in Chinese herbal drugs.

 

 

Indian Journal of Chemistry
Vol. 41A, November  2002, pp 2318-2320

 

Ion exchange kinetics of alkaline earth metals on acrylamide zirconium(IV) phosphate cation exchanger

 

K G Varshney*, Vandana Jain & Namrta Tayal

           The kinetics of Mg(II), Ca(II), Sr(II) and Ba(II) exchange with H(I) on acrylamide zirconium(IV) phosphate has been studied applying the Nernst-Planck equation. The rate of exchange is found to be particle diffusion controlled at a metal ion concentration ≥ 0.01M in aqueous medium. The energy and entropy of activation vary linearly with the ionic radii and mobilities.