Total visitors:3,662 since 31-08-04

Indian Journal of Chemistry

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

 

 

 

VOLUME 43A

NUMBER 8

AUGUST 2004

 

 

CONTENTS

 

Rapid Communication

 1595

 Isolation and X-ray structure of a mixed ligand ruthenium(II) intermediate that contains both ArNH2 and CH3CN as ligands

 

Anasuya Sanyal, Amrita Saha, Kedar N Mitra, Shie-Ming Peng, Gene-Hsiang Lee & Sreebrata Goswami*

 

 

Advances in Contemporary Research

1599

Electrochemical generation of ozone using solid polymer electrolyte – State of the art

 

Sang-Do Han, J D Kim, K C Singh*  & R S Chaudhary

 

Electrochemical generation of ozone using solid polymer electrolyte, fabrication of the electrochemical cell, deposition and mechanism of the anode and cathode catalysts, preparation of current collectors and optimum conditions for the proton exchange membrane, cell assembly and high ozone current efficiency have been reviewed.

Papers

1615

Electron content and electron excess of rings of benzenoid hydrocarbons

 

 

 

Ivan Gutman

 

 

1619

Electronic structure of model protein chains: Effect of basis set and secondary structure

 Shyam Kishor & A K Bakhshi*

 

Ab initio band structure results of b-pleated polyglycine, polyalanine, and polyserine, obtained using minimal basis set, have been used as input to calculate the electronic density of states of different periodic and aperiodic model protein chains on the basis of negative factor counting method in tight binding approximation.

 1626

Synthesis, crystal structure and magnetic properties of polymeric tetrakis(pyrazolyl) borate copper(II) complexes

 

Anitha M Thomas, Arindam Mukherjee, Manas K Saha, Munirathinam Nethaji & Akhil R Chakravarty*

 

 

 1635

 Hydrothermal synthesis and crystal structure of aqua (pyridine- 2,6-dicarboxylato)  (1,10-phenanthroline) cobalt(II)  dihydrate

 

Sudalaiandi Kumaresan*, Palani Ramadevi & Shaikh M Mobin

 

 

1639

Kinetics of oxidative decarboxylation and deamination of L-glutamine by diperiodatonickelate(IV) in aqueous alkaline medium

 

M B Bellakki, R T Mahesh & S T Nandibewoor*

 

The kinetics of oxidation of L-glutamine by diperiodatonickelate (IV) (DPN) in aqueous alkaline medium at a constant ionic strength of 0.5 mol dm-3 has been studied spectrophotometrically. The reaction is first order in [DPN] and is an apparent less than unit order each in [L-glutamine] and [alkali] under the experimental conditions. However, the order in [L-glutamine] and [alkali] changes from first order to zero order as their concentrations increase.

1645

Kinetics of oxidation of crotonic acid by sodium N-chloro-p-toluenesulphonamide in the presence of pd(II) and Os(VIII) as homogeneous catalysts

Ashish, Ajaya kumar Singh, Ashok Kumar Singh & Bharat Singh*

 

The kinetics of Pd(II) and Os(VIII) catalysed oxidation of crotonic acid by chloramine-T in perchloric acid have been investigated. The reactions are zero order in [chloramine-T] and first order each in both [Pd(II)] and [Os(VIII)], while first order in [crotonic acid] at lower concentrations tending towards zero order at its higher concentrations .

Notes

1654

 

 

 

 

 

Synthesis, characterization and in vitro anticancer activities of semicarbazone and thiosemicarbazone derivatives of salicylaldehyde and their copper complexes against human breast cancer cell line MCF-7

Jayendra Patole, Shreelekha Padhye, Subhash Padhye*, C J Newton & Christopher Anson & A K Powell

 

 

 

1659

Synthesis and crystal structure of dimeric silver(I) complex: Ag2[phen]2[S2P(OPr)2]2

 

 

Fangfang Jian*, Hailian Xiao &
Huanxiang Wang

 

1662

 Reactivity and structural study of boron complexes with biochemical aspects

Mukesh Kumar Biyala, Nighat Fahmi & R V Singh*

 

Boron(III) complexes of 6-nitro-3-(indolin-2-one) hydrazinecarbothioamide, 6-nitro-3-(indolin-2-one) hydrazinecarboxamide, 5,7-dimethyl-3-(indolin-2-one) hydrazinecarbothioamide and 5,7-dimethyl-3-(indolin-2-one) hydrazinecaboxamide, have been synthesized and characterized by physico-chemical and spectroscopic analysis.

 1667

Triphenylantimony(V)dichloride molecular adducts with some thiosemicarbazones

Kishori Dalvi, Mamta Pal & Shivram S Garje*

 

 

1672

Synthesis and characterization of organotin(IV) complexes of p-phenylphenol

Neeraj Sharma*, S S Pathania, Archana, S S Bhatt & S C Chaudhry

 

 

 1676

 Catalytic oxidation of benzyl alcohol by Al3+ doped manganese oxide of the type OMS–2 using molecular oxygen or air

 Jeanette S Rebello, Sajo P Naik & Julio B Fernandes*

 

Oxidation of benzyl alcohol to benzaldehyde using molecular oxygen over manganese oxides of the type OMS-2 is reported. Al3+- doped OMS-2 has significantly higher activity (~ 58%) as compared to pure OMS-2 (~ 43 %). Catalytic activity depends on the ease of availability of lattice oxygen and presence of Mn4+/Mn3+ redox couple.

 1680

 Kinetics and mechanism of catalytic carboxyester hydrolysis using Zn(II) complexes of 1,3,5-tri-(N-α-pyridylmethylenic amino-methylenic) benzene

Xiao-jun Zhao*, En-cui Yang, Hua-kuan Lin & Jianhua Guo

 

Zn(II) complex with a novel tripod ligand has been examined as a catalyst for the hydrolysis of 4-nitrophenyl acetate (NA). The results show that Zn(II) complex serves as a good nucleophile that effectively catalyzes NA hydrolysis. The hydrolysis follows the rate law
v= (k  [complex]+kOH[OH-]+k0)[NA].

1685

PVC membrane based potentiometric sensor for uranyl ion using thenoyl trifluoro acetone as ionophore

 

 

D Nanda, H P S Chouhan & B Maiti*

 

Uranyl ion selective electrode based on thenoyl trifluoro acetone incorporated into a polyvinyl chloride membrane has been developed where dibutyl phthalate and sodium tetraphenyl borate have been used as plasticizer and anion excluder respectively. The electrode shows near Nernstian response to UO22+ in the concentration range of 10-1 to 10-6, mol L-1 with an average slope of 30 mV/decade.

 1689

Effect of film charge on the mid-point potential of encapsulated ferrocene

Raben Ch Roy, Rimki Bhattacharjya & Diganta Kumar Das*

 

Neutral surfactant films shift the mid-point potential of ferrocene cathodically by 150 mV as compared to organic solvents. Films with negative charge make a further cathodic shift of 50 mV in mid-point potential. On the other hand, when the film has positive charge, there is about 35 mV anodic shift in mid-point potential as compared to neutral films.

 1692

Electric-dipole intensity of nona-coordinated complexes of Nd(III) with diols in non-aqueous solution : Evidence of participation of p-electron density of diols with Nd(III)

 M Indira Devi

 

Intensity difference and comparative absorption spectrophotometric studies involving 4f-4f transition of neodymium(III) and different diols (butane 1,4-diol, butene 1,4-diol and butyne 1,4-diol) have been carried out in DMF and CH3OH as well as in equimolar mixtures of DMF +CH3CN, DMF + CH3CN, DMF + dioxane, CH3OH + CH3CN and CH3CN + dioxane.

 1696

Preparation, molecular weight determination and structure elucidation of melamine-urea-formaldehyde, melamine–methylurea-form-aldehyde and melamine-dimethylurea-form-aldehyde polymer resins with IR spectroscopy

Man Singh

 

 Melamine-urea-formaldehyde, melamine-methylurea-formaldehyde and melamine-dimethylurea-formal-dehyde resins/polymers have been prepared by condensation polymerization. Hydrogen atom substitution by methyl group in urea increases the average molecular weights. IR spectra indicate the presence of several oligomer units with methylene and ether linkages.

 Authors for correspondence are indicated by (*)

 

 

 

Indian Journal of Chemistry

 Vol. 43A, August 2004, pp. 1595-1598

 

Isolation and X-ray structure of a mixed ligand ruthenium(II) intermediate
that contains both ArNH2 and CH3CN as ligands

Anasuya Sanyal, Amrita Saha, Kedar N Mitra, Shie-Ming Peng,

Gene-Hsiang Lee &  Sreebrata Goswami

 

Solvolysis of the complex [RuCl2(PhNH2)2(L)], 1, (L= diim= N-phenyl-1,2-benzoquinonediimine) in acetonitrile has been studied. A mixed ligand complex of composition [RuCl(PhNH2)2(CH3CN)(L1)]Cl. H2O, 2, has been isolated and characterized. Lability of Cl in 1, is ascribed to strong trans directing ability of the diimine ligand. The compound, 2, is trans with respect to two PhNH2; Cl and CH3CN occupy relative cis positions. The C-N bond length of the chelate ring and C-C bond length within the quinonoid ring confirm the diimine oxidation state of the bidentate ligand. The Ru-N (diim) lengths are appreciably shorter than the Ru-N(aniline) lengths, indicating Ru(II)dppp (diim) interaction. Redox as well as spectral properties of the reference complex are reported.

 

IPC Code: Int. Cl.7 C07F 15/00

 

 

 

Indian Journal of Chemistry

Vol. 43A, August 2004, pp. 1599-1614

 

Electrochemical generation of ozone using solid polymer electrolyte – State of the art

Sang-Do Han*, Jung Duk Kim, K C Singh* & R S Chaudhary

 

In this review article, up-to-date information about the electrochemical generation of ozone using solid polymer electrolyte, fabrication of the electrochemical cell, deposition and mechanism of the anode and cathode catalysts, preparation of current collectors and optimum conditions for the proton exchange membrane, cell assembly and high ozone current efficiency have been described.

 

IPC Code: Int. Cl.7 C01B 13/10; C25B 1/13

 

 

 

Indian Journal of Chemistry

 Vol. 43A, August 2004, pp. 1615-1618

 

Electron content and electron excess of rings of benzenoid hydrocarbons

Ivan Gutman*

 

The π-electrons can be distributed into the rings of a benzenoid molecule by means of a reasoning based on Kekulé structures. The distribution thus obtained is often, but not always, in agreement with the Clar aromatic sextet theory. Using the concept of π-electron excess of a ring, the agreement between the Clar-theory-based and the Kekulé-structure-based pictures is further improved.

 

 

 

Indian Journal of Chemistry

Vol. 43A, August 2004, pp. 1619-1625

 

Electronic structure of model protein chains: Effect of basis set and secondary structure

Shyam Kishor & A K Bakhshi*

 

Ab initio band structure results of b-pleated polyglycine, polyalanine, and polyserine obtained using minimal basis set have been used as input to calculate the electronic density of states of different periodic and aperiodic model protein chains on the basis of negative factor counting method in tight binding approximation. The effects of the change of the basis set (double-zeta) and the secondary structure (a-helix) on the electronic density of states of these model protein chains have also been investigated.

 

 

 

Indian Journal of Chemistry

Vol. 43A, August 2004, pp. 1626-1634

 

Synthesis, crystal structure and magnetic properties of polymeric
tetrakis(pyrazolyl)borate copper(II) complexes

Anitha M Thomas, Arindam Mukherjee, Manas K Saha,

Munirathinam Nethaji & Akhil R Chakravarty*

 

Polynuclear copper(II) complexes [Cu2{m-B(pz)4}(m-ox)(NO3)(H2O)].2H2O (1.2H2O), [Cu2{m-B(pz)4}(m-ox)(H2O)2](ClO4).2H2O (2.2H2O) and [Cu2{m-B(pz)4}(m-NO3)(NO3)2(H2O)] (3) are prepared and structurally characterized by single crystal X-ray crystallography (ox, oxalate ion C2O42-). Complexes 1 and 2 have oxalate and tetrakis(pyrazolyl)borate bridging ligands to form one-dimensional (1D) chains. The coordinating atoms of the oxalate and tetrakis(pyrazolyl)borate in 1 and 2 occupy the basal positions giving CuN2O3 square pyramidal geometry. The alternate copper centers in 1 are bonded to nitrate and aqua axial ligands. Complex 2 has each copper bonded to one axial aqua ligand. In the 1D polymeric structure of complex 3, the copper(II) centers are linked through nitrate and tetrakis(pyrazolyl)borate ligands. Each copper atom has a distorted octahedral CuN2O4 coordination geometry with two long Cu-O bonds. The electronic spectra of the complexes 1-3 display a broad d-d band within 676-721 nm in DMF. Variable temperature magnetic susceptibility measurements in the range 20 to 300 K show strong antiferromagnetic behavior of the complexes 1 and 2 giving respective magnetic moment values of 1.49 and 1.52 mB (per copper) at 298 K. The coplanar orbital topology involving the {Cu2(m-ox)}2+ moiety in 1 and 2 facilitates strong antiferromagnetic coupling between two {} magnetic orbitals (J: -320 cm-1 1; -353 cm-1 2). Complex 3 is essentially paramagnetic giving meff value of 1.93 mB (per copper) in the temperature range 20 to 300 K. Such a magnetic behavior arises due to orthogonality of the orbital overlap arising from the axial-equatorial bridging mode of the nitrate ligand. In 1-3, the tetrakis(pyrazolyl)borate bridging ligand is apparently ineffective in mediating magnetic exchange interaction due to non-availability of orbitals for exchange interactions. The complexes show the formation of different supramolecular net-work structures due to hydrogen bonding interactions.

 

IPC Code: Int. Cl.7 C07F 1/08; C07F 5/02

 

 

 

Indian Journal of Chemistry

 Vol. 43A, August 2004, pp. 1635-1638

 

Hydrothermal synthesis and crystal structure of aqua(pyridine - 2,6-dicarboxylato)(1,10-phenanthroline)cobalt(II) dihydrate

Sudalaiandi Kumaresan*, Palani Ramadevi & Shaikh M Mobin

 

Hydrothermal reaction of cobalt(II) acetate with pyridine-2,6-dicarboxylic acid and 1,10-phenanthroline has afforded aqua(pyridine-2,6-dicarboxylato)(1,10-phenanthroline)cobalt(II) dihydrate (1). X-ray structure determination shows that complex 1 crystallized in the triclinic space group P-1. A one-dimensional assembly has been formed by the intermolecular p-p interactions between the 1,10-phenanthroline units.

 

IPC Code: C07F 15/06

 

 

 

Indian Journal of Chemistry

 Vol. 43A, August 2004, pp. 1639-1644

 

Kinetics of oxidative decarboxylation and deamination of L-glutamine by
diperiodatonickelate(IV) in aqueous alkaline medium

M B Bellakki, R T Mahesh & S T Nandibewoor*

 

The kinetics of oxidation of L-glutamine by diperiodatonickelate (IV) (DPN) in aqueous alkaline medium at a constant ionic strength of 0.5 mol dm-3 has been studied spectrophotometrically. The reaction is first order in [DPN] and is an apparent less than unit order, each in [L-glutamine] and [alkali] under the experimental conditions. However, the order in [L-glutamine] and [alkali] changes from first order to zero order as the concentrations change from lower to higher concentrations. Addition of periodate has no effect on the rate of reaction. Effect of added products, ionic strength and dielectric constant of the reaction medium have been investigated. A mechanism involving the deprotonated diperiodatonickelate(IV) as the reactive species of the oxidant has been proposed. The reaction constants involved in the different steps of mechanism are evaluated and thermodynamic quantities are also calculated.

 

IPC Code: Int. Cl.7 C07B 37/06

 

 

 

Indian Journal of Chemistry

Vol. 43A, August 2004, pp. 1645-1653

 

Kinetics of oxidation of crotonic acid by sodium N-chloro-p-toluenesulphonamide
in the presence of pd(II) and Os(VIII) as homogeneous catalysts

Ashish, Ajaya kumar Singh, Ashok Kumar Singh & Bharat Singh*

 

The kinetics of Pd(II) and Os(VIII) catalysed oxidation of crotonic acid (CA) by chloramine-T (CAT) in perchloric acid have been investigated. The reactions are zero order in [chloramine-T] and first order each in both [Pd(II)] and [Os(VIII)], while first order in [CA] at lower concentrations tending towards zero order at its higher concentrations. Positive effect of added [Cl-] and zero effect of added p-toluenesulphonamide (PTS) have been observed in Pd(II) catalysed reaction, while in Os(VIII) catalysed reaction negative effect of PTS on rate of reaction has been observed. Negligible effect of change in [H+] and ionic strength of the medium, and rate decrease with decrease in dielectric constant of the medium have been observed in both Pd(II) and Os(VIII) catalysed reactions. The catalytic efficiency is in the order, Pd(II) > Os(VIII). The products of oxidation in both reactions are acetaldehyde and glyoxylic acid. Activation parameters have been computed and mechanistic steps, consistent with the kinetic results, reaction stoichiometry and product analysis for both catalysed reactions have been discussed.

 

IPC Code: Int. Cl.7 B01J 23/44; B01J 27/185; C07B 33/00

 

 

 

Indian Journal of Chemistry

 Vol. 43A, August 2004, pp. 1654-1658

 

Synthesis, characterization and in vitro anticancer activities of semicarbazone and thiosemicarbazone derivatives of salicylaldehyde and their copper complexes against human breast cancer cell line MCF-7

Jayendra Patole, Shreelekha Padhye, Subhash Padhye*, C J Newton,

Christopher Anson & A K Powell

 

Copper complexes of salicylaldehyde semi-/thiosemicarbazones are prepared and characterized structurally through their X-ray structures. The chloro compound of the semicarbazone ligand is monomeric having square planar geometry while the nitro complex is dimeric containing phenoxyl bridges. The chloro complex of the thiosemicarbazone derivative is dimeric where individual copper centres possess square pyramidal geometries. The parent ligands are almost inactive against the rapidly dividing human breast cancer cell line MCF-7 while the copper conjugates of semicarbazone ligand are found to be potent antiproliferative agents due to their facile Cu2+/Cu+ redox couple and can generate considerable intracellular oxidative stress.

 

IPC Code: Int. Cl.7 C07C 281/08; C07F 1/08

 

 

 

Indian Journal of Chemistry

 Vol. 43A, August 2004, pp. 1659-1661

 

Synthesis and crystal structure of dimeric silver (I) complex: Ag2[phen]2[S2P(OPr)2]2

Fangfang Jian*, Hailian Xiao & Huanxiang Wang

 

The dinuclear complex, Ag2[phen]2[S2P(OPr)2]2 (phen = 1,10-phenanthroline; Pr = propyl), was prepared by the reaction of bis(dipropyldithiophosphato)silver(I) complex with 1,10-phenanthroline ligand, and its structure was determined by X-ray crystallography. It crystallizes in the triclinic system, space group Pī, with lattice parameters a = 9.875(2), b = 10.992(2), c = 11.232(2) Ĺ, α = 68.32(3), β = 74.93(3), γ = 65.16(3)o, and Z = 2. Each of the two dipropyldithiophosphato ligands bridges two silver atoms to form an eight-membered Ag2S4P2 ring, while the 1,10-phenanthroline coordinates to the silver atom to complete the local tetrahedral geometry for the silver metal ion. The Ag…Ag separation in the dimer is 3.207(1) Ĺ.

 

IPC Code: Int. Cl.7 C07F 1/10

 

 

 

Indian Journal of Chemistry

 Vol. 43A, August 2004, pp. 1662-1666

 

Reactivity and structural study of boron complexes with biochemical aspects

Mukesh Kumar Biyala, Nighat Fahmi & R V Singh*

 

Boron(III) complexes of 6-nitro-3-(indolin-2-one)hydrazine-carbothioamide(L1H), 6-nitro-3-(indolin-2-one) hydrazinecarboxamide(L2H), 5,7-dimethyl-3-(indolin-2-one)hydrazinecarbothio-amide(L3H) and 5,7-dimethyl-3-(indolin-2-one)hydrazinecarbo-xamide (L4H), have been synthesized and characterized by physico-chemical and spectroscopic means. The complexes [(Ph)B(OH)(L)] and [(Ph)B(L)2] (where L represents the deprotonated form of the ligand LH) are formed by the reactions between phenyldihydroxyborane and the ligands L1H, L2H, L3H and L4H. Chemical analysis, conductance measurements, molecular weight determinations and spectral data of these complexes including IR, UV-visible, 1H NMR, 13C NMR and 11B NMR have been performed. The data suggest that the ligands coordinate to the boron atom in a monobasic bidentate way coordinating through oxygen/sulfur and nitrogen atom. Thus, a tetracoordinated environment around the boron atom has been proposed. To discuss bio-inorganic aspects of the complexes, representative free ligands and their boron complexes were screened for their antimicrobial activity. The results show that the ligands and boron complexes exhibit antimicrobial activity.

 

IPC Code: Int. Cl.7  C07F 5/02

 

 

 

Indian Journal of Chemistry

 Vol. 43A, August 2004, pp. 1667-1671

 

Triphenylantimony(V)dichloride molecular adducts with some thiosemicarbazones

Kishori Dalvi, Mamta Pal & Shivram S Garje*

 

The reaction of triphenylantimony(V)dichloride with one mole equivalent of thiosemicarbazone ligands yields the molecular adducts of the type Ph3SbCl2. NÇS (NÇS = thiosemi­carbazones). These compounds have been characterized by elemental analysis, IR and 1H and 13C NMR spectral data and conductometric measurements. The structures of these molecular adducts have been proposed on the basis of spectroscopic data.

 

IPC Code: Int. Cl.7 CO7F 9/92

 

 

 

Indian Journal of Chemistry

 Vol. 43A, August 2004, pp. 1672-1675

 

Synthesis and characterization of organotin(IV) complexes of p-phenylphenol

Neeraj Sharma*, S S Pathania, Archana, S S Bhatt & S C Chaudhry

 

The di- and tri-organotin(IV) complexes with the composition R2SnCl2-n(OC6H4Ph-p)n and (C6H5)3Sn(OC6H4Ph-p) (R = n-C4H9 and Me; n = 1 and 2) have been synthesized by the reaction of dialkyl and triphenyltin(IV) chlorides with p-phenylphenol in the presence of diethylamine in diethylether at room temperature. The complexes have been characterized by their analytical data and IR and 1H NMR spectra. Thermal behaviour of the complexes has been studied by TGA/ DTA methods. Lewis acid character of the complexes has been established by reacting them with nitrogenous bases such as 2,2΄- bipyridyl, 1,10- phenanthroline and 2,2΄- dipyridylamine.

 

IPC Code: Int. Cl.7 C07F 7/22

 

 

 

Indian Journal of Chemistry

 Vol. 43A, August 2004, pp. 1676-1679

 

Catalytic oxidation of benzyl alcohol by Al3+ doped manganese oxide of the type
OMS–2 using molecular oxygen or air

Jeanette S Rebello, Sajo P Naik & Julio B Fernandes*

 

The oxidation of benzyl alcohol to benzaldehyde using molecular oxygen over manganese oxides of the type OMS-2 is reported. It is observed that Al3+- doped OMS-2 has significantly higher activity (~ 58%) as compared to pure OMS-2 (~ 43 %). The catalysts are characterized by XRD, IR, H+ ion exchangeability, thermal analysis, BET surface area and temperature programmed desorption (TPD) of ammonia. Catalytic activity depends on the ease of availability of lattice oxygen and presence of Mn4+/Mn3+ redox couple. The activity of the catalysts has been correlated with various physicochemical characteristics, like surface area and concentration of acid sites.

 

IPC Code:B01J 23/16; C07B 33/00

 

 

 

Indian Journal of Chemistry

 Vol. 43A, August 2004, pp. 1680-1684

 

Kinetics and mechanism of catalytic carboxyester hydrolysis using Zn(II) complexes of 1,3,5-tri-(N-α-pyridylmethylenic aminomethylenic) benzene

Xiao-jun Zhao*, En-cui Yang, Hua-kuan Lin & Jianhua Guo

 

Zn(II) complex with a novel tripod ligand has been examined as a catalyst for the hydrolysis of 4-nitrophenyl acetate (NA). The kinetics of hydrolysis has been investigated by observing the rate of release of p-nitrophenolate ion in the buffers at 278 K and at different pH. The new ligands form a 1:3(ligand: zinc) zinc complex in the pH range 7.5~9.4. The kinetic studies have been performed using the zinc complexes in 10% (v/v) CH3CN at 278K, I = 0.10 mol×dm-3 KNO3 and pH 7.5~9.4. The results show that Zn(II) complex serves as a good nucleophile that effectively catalyzes NA hydrolysis. The hydrolysis rate follows the law v= (k[complex]+kOH[OH-]+k0)[NA]. The second order hydrolysis rate constant using Zn3LH-1 is 0.371mol-1 dm3s-1, which obviously is larger than the corresponding value using other Zn(II) complexes of multidentate ligands.

 

IPC Code: Int. Cl.7 B01J 23/06; C07B 41/12

 

 

 

Indian Journal of Chemistry

Vol 43A, August 2004, pp.1685-1688

 

PVC membrane based potentiometric sensor for uranyl ion using
thenoyl trifluoro acetone as ionophore

D Nanda, H P S Chouhan & B Maiti*

 

Uranyl ion selective electrode based on thenoyl trifluoro acetone (TTA) incorporated into a polyvinyl chloride (PVC) membrane has been developed where dibutyl phthalate and sodium tetraphenyl borate have been used as plasticizer and anion excluder respectively. The PVC membrane containing the active ionophore, TTA, and the other ingredients has been directly cast on a graphite electrode. The electrode shows near Nernstian response to UO22+ in the concentration range of 10-1 to 10-6 mol. L-1 with an average slope of 30 mV/decade. Alkali and alkaline earth metal ions do not interfere with the determination of uranyl ion. Interference of transition metal ions and Th (IV) is eliminated with EDTA.

 

IPC Code: Int. Cl7. G01N 27/00

 

 

 

Indian Journal of Chemistry

 Vol. 43A, August 2004, pp.1689-1691

 

Effect of film charge on the mid-point potential of encapsulated ferrocene

Raben Ch. Roy, Rimki Bhattacharjya & Diganta Kumar Das*

 

Neutral surfactant film shifts cathodically the mid-point potential of ferrocene by 150 mV compared to organic solvent. Film with negative charge makes a further cathodic shift in mid-point potential of 50 mV. On the other hand, when the film has positive charge there is about 35 mV anodic shift in mid-point potential compared to neutral film. The nature of charge of the film can vary the mid-point potential of ferrocene over a range of 75 mV.

 

IPC Code: Int. Cl7. C25

 

 

 

Indian Journal of Chemistry

Vol. 43A, August 2004, pp.1692-1695

 

Electric-dipole intensity of nona-coordinated complexes of Nd(III) with diols in non-aqueous solution: Evidence of participation of p-electron density of diols with Nd(III)

M Indira Devi

 

Intensity difference and comparative absorption spectrophotometric studies involving 4f-4f transition of neodymium(III) and different diols (butane 1,4-diol, butene 1,4-diol and butyne 1,4-diol) have been carried out in DMF and CH3OH as well as in equimolar mixtures of DMF +CH3CN, DMF + CH3CN, DMF + dioxane, CH3OH + CH3CN and CH3CN + dioxane. The small chemical and structural differences in the ligands and solvents produce significant variation in the intensities of observed 4f-4f absorption bands and their relative perturbation on 4f-4f transition intensities are readily apparent in the Judd-Ofelt electric dipole parameters. Correlations made from the plot of oscillator strength (Pobs) against Tl parameters, which represent the relative sensitivities of different 4f-4f absorption bands, reveal the involvement of π-electron density of diols in complexation with Nd(III).

 

IPC Code: Int. Cl.7 C08G 59/70

 

 

 

Indian Journal of Chemistry

 Vol. 43A, August 2004, pp. 1696-1700

 

Preparation, molecular weight determination and structure elucidation of melamine-urea-formaldehyde, melamine-methylurea-formaldehyde and melamine-dimethylurea-formaldehyde polymer resins with IR spectroscopy

Man Singh

 

Melamine-urea-formaldehyde (MUF), melamine-methylurea-formaldehyde (MMUF) and melamine-dimethylurea-formal-dehyde (MDUF) resins/polymers have been prepared by condensation polymerization. Average molecular weights (Mw) have been determined with intrinsic viscosity and gel permeation chromatography (GPC) with known molecular weights of polyvinyl alcohol as standard marker for calibration. Hydrogen atom substitution by methyl group in urea increases Mw and IR spectra mark the presence of several oligomer units with methylene and ether linkages. Disappearance of 3734 cm-1 band from spectra of uncured MUF on curing from 140 to 200°C has been noticed with narrowness in bands and multiple splits between 3451 and 3296 at 140°, 3453 and 3328 at 160° and 3341 and 3234 cm-1 doublet at 200°C.

 

IPC Code: Int. Cl.7 C 08 G 12/12