Indian Journal of Chemistry

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

 

VOLUME 46A

NUMBER 7

July 2007

 

CONTENTS

 

 

1057

 

Synthesis, crystal structure and fluorescence studies of two manganese(III) complexes of aminebis(phenolate) ligands

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Dipankar Maity, W S Sheldrick, H Mayer-Figge & Mahammad Ali*

 

 

 

Two manganese(III) complexes, [MnIII(L1)(N3)(MeOH)] and [MnIII(L2)(N3)(MeOH)] where, H2L1 = N,N-bis(2- hydroxy-3-5-di-tetrt-butylbenzyl)-N′,N′-dimethyl ethylenediamine and H2L2 = N,N-bis(2-hydroxy-3-5-dimethylbenzyl)-N′,N′-dimethyl ethylene-diamine have been synthesized and characterized.

 

 

1063

 

Characterization of novel diorganotin(IV) complexes with O,N,O donor ligand derived from carbohydrazide: X-ray crystal structure of [Ph2Sn(H2CBS)]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

M A Affan*, Y Z Liew, Fasihuddin B Ahmad, Mustaffa B Shamsuddin & Bohari M Yamin

 

 

 

A new series of diorganotin(IV) complexes has been synthesized by the reaction of R2SnCl2 (R = Me, Bu and Ph) with O,N,O-tridentate carbohydrazone ligand derived from carbohydrazide. Three diorganotin(IV) complexes of carbohydrazone-bis(salicylaldehyde) ligand [H4CBS] with R2SnCl2 have been synthesized by refluxing in the presence of base in 1:2:1 molar ratio (metal:base:ligand).

 

 

 

1069

 

New multi-site phase transfer catalyst for the addition of dichlorocarbene to olefins

 

 

 

 

 

K Shanmugan* & T Balakrishnan

 

 

 

Three step synthesis of a new, water-soluble multi-site phase transfer catalyst (MPTC-I), viz., a,a1,a11-tris(triethyl ammonium methylene bromide) b-hydroxy ethyl benzene is described. The potentiality of MPTC-I is demonstrated by studying kinetic aspects of the reactions, viz., dichlorocarbene addition to styrene, a-methyl styrene and trans-stilbene.

 

1075

 

Studies on the middle phase microemulsion of alkyl polyglucoside

 

 

 

 

 

 

 

Jinling Chai* , Xiaodeng Yang, Yanhong Gao & Changju Wu

 

 

 

The middle phase microemulsions of alkyl polyglucosides (APG) C8G1.46, C10G1.46, C12G1.46, C8/10G1.31 and C12/14G1.43 have been studied with the alcohol concentration scanning phase diagram. The results show that in the quaternary system of APG/ alcohol/ alkane/ water, the increase in the alcohol concentration causes a series of phase inversion Winsor I (2) →III(3) →II(). The order of the alcohol width and the minimum alcohol concentration needed to form middle phase microemulsion is: C8G1.46>C8/10G1.31>C10G1.46>C12G1.46>C12/14G1.43.

 

 

1081

 

Autoprotolysis constants of ethylene glycol in isodielectric mixtures of ethylene glycol and
N,N-dimethyl formamide at 298.15 K and the related Gibbs energies of transfer

 

 

 

 

 

 

 

B K Dolui, S K Bhattacharya* & K K Kundu

 

 

 

Autoprotolysis constants (Ks) of ethylene glycol (EgOH) in isodielectric mixtures of EgOH and DMF have been determined by use of cells comprising GE (H+) and AgCl-Ag electrodes at 298.15 K and the related transfer Gibbs energies, ΔGot of EgO- have been evolved by use of literature values of ΔGot(H+) based on TATB assumption. The results reflect that while acidity of the mixed solvents is governed by the increased aproticity and increased anionophobicity of DMF, the basicity is dictated by the increased aproticity and protophilicity of DMF molecule.

 

 

1090

 

Oxidation of hexacyanoferrate(II) by peroxodisulphate in aqueous perchloric acid ¾ A kinetic and mechanistic study

 

 

 

 

 

 

 

 

 

S A Chimatadar, S V Madawale, K A Thabaj & S T Nandibewoor*

 

 

 

The kinetics of the reaction between hexacyanoferrate(II) and peroxodisulphate has been studied spectroscopically in perchloric acid. The reaction is first order each in peroxodisulphate and hexacyanoferrate(II) concentrations.

 

 

1095

 

Fluorescence and absorption studies on the selective recognition of iodide by lower rim 1,3-bis-(aminoethoxy)-p-t-butyl-calix[4]arene derivative

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Roymon Joseph, Ankur Gupta, Amjad Ali & Chebrolu P Rao*

 

 

 

Lower rim 1,3-bis(aminoethoxy)-p-t-butyl-calix[4]arene derivative has been subjected to fluorescence and absorption studies to evaluate its utility to recognize halides. This derivative has been found to be selective towards iodide, immaterial of its counter cation as well as the presence of other halide ions.

 

 

Notes

 

1101

 

Determination of the product yield of SO molecules formed by the reaction of H atom with SO2 at high temperatures

 

 

 

 

Yoshinori Murakami*, Shouichi Onishi &Nobuyuki Fujii

 

 

 

The product yield of SO molecules by the reaction H + SO2 has been investigated by monitoring the molecular absorption of SO molecules at 151 nm behind the reflected shock of C2H5I / SO2 / Ar mixtures by comparing the intensity of SO absorption using thermal decomposition of the SO2 system. It has been found that the product yield of SO is 40 – 60%. It is suggested that
H + SO2 → OH + SO is one of the major pathways for the reaction of H atoms with SO2 at temperatures above 1400 K.

 

 

1105

 

Unsymmetrically substituted organotin(IV) N-alkyl, N-hydroxyethyl dithiocarbamates: Synthesis and spectral aspects

 

 

 

 

 

 

 

 

 

 

 

 

S K Srivastava*, H Pandey & R Sharma

 

 

 

Unsymmetrically substituted triphenyltin(IV) N-alkyl,
N-hydroxyethyl dithiocarbamates, [(C6H5)3SnS(S) CN(R)- CH2CH2OH] [R=CH3, C2H5], diphenyltin(IV) bis(N-alkyl,
N-hydroxyethyl dithiocarbamates), [(C6H5)2Sn{S(S)CN(R)-CH2CH2OH}2], [R=CH3, C2H5] and chlorodiphenyltin(IV)
N-alkyl, N-hydroxyethyl dithiocarbamates, [(C6H5)2Sn (Cl)S- (S)CN(R)CH2CH2OH] [R=CH3, C2H5] have been synthesized and characterized.

 

 

 

1109

 

Synthesis, spectroscopic and electrochemical studies of novel transition metal complexes with N,N'-
bis(2-hydroxynaphthalin-1-carbaldehydene)-1,3-bis-(o-aminophenoxy) propane

 

 

 

 

 

 

 

 

 

 

 

Hamdi Temel*, Salih İlhan, Mehmet Aslanoğlu & Hüseyin Alp

 

 

 

A novel Schiff base obtained by the reaction of 1,3-bis-
(o-aminophenoxy)propane and 2-hydroxynaphthalin-1-carbaldehyde,
forms complexes with Co(II), Cu(II) and Ni(II).

 

 

 

 

1113

 

Synthesis and characterization of new complexes formed by insertion of carbon disulphide in RuL3Cl3 (L=PPh3 and AsPh3)

 

 

 

 

 

 

Pradip K Gogoi*, Geetika Borah*,
Nayanmoni Bharali & Diganta Saikia

 

 

 

Reaction of RuL3Cl3 (L=PPh3 and AsPh3) with stoichiometric amount of CS2 in ethanol-dichloromethane mixed solvent systems at room temperature yields paramagnetic complexes of the type [RuL2Cl2(S2COEt)]. The complexes have been characterized by conductance, IR, electronic, ESR spectral, magnetic moment measurement and thermal data as well as by elemental analysis. The appearance of three g-values in the ESR spectra reveals a highly distorted octahedral environment around ruthenium(III) ion with one bidented EtOCS2ˉ ligand.

 

 

1116

 

Inhibition effect of Brij-35 on the rate of
oxidation of ascorbic acid by hexacyanoferrate(III) in acidic medium: A kinetic study

 

 

 

 

 

 

 

 

Ratna Shukla & Santosh K Upadhyay*

 

 

 

The effect of non-ionic surfactant, i.e., Brij-35, polyoxy-ethylene(23)laurylether, on the rate of oxidation of ascorbic acid by hexacyanoferrate(III) in acidic (HClO4) medium has been studied spectrophotometrically in the temperature range 30-50°C. The rate of oxidation is inhibited in presence of Brij-35 even below the critical micelle concentration of the surfactant. A mechanism of oxidation in presence of the surfactant is proposed. The binding parameters between the surfactant and ascorbic acid have been evaluated using Menger and Portnoy’s  model reported for micellar catalysis/inhibition.

 

 

1121

 

A pulse polarographic method for the analysis of zinc dithiocarbamates

 

 

 

 

 

 

 

D K Sharma*, Satish Kumar, Chetan Chauhan & Atul Gupta

 

 

 

An extremely sensitive pulse polarographic method for the determination of zinc dimethyldithiocarbamate (an agricultural fungicide) and zinc di-n-pentyldithiocarbamate (a petroleum additive), has been developed based on the reaction of their dithiocarbamate moiety with copper(II) perchlorate in acetonitrile medium. Using cyclic voltammetry, a probable mechanism for the zinc dithiocarbamate-copper(II) reaction has been proposed.

 

 

Authors for correspondence are indicated by (*)


 

Indian Journal of Chemistry

Vol. 46A, July 2007, pp. 1057-1062

 

Synthesis, crystal structure and fluorescence studies of two manganese(III) complexes of aminebis(phenolate) ligands

Dipankar Maity, W S Sheldrick, H Mayer-Figge & Mahammad Ali*

Received 8 February 2007; revised 28 May 2007

Two manganese(III) complexes, [MnIII(L1)(N3)(MeOH)] (1) and [MnIII(L2)(N3)(MeOH)] (2) where, H2L1 = N,N-bis(2-hydroxy-3-5-di-tert-butylbenzyl)-N′,N′-dimethyl ethylenediamine and H2L2 = N,N-bis(2-hydroxy-3-5-dimethylbenzyl)- N′,N′-dimethyl ethylenediamine have been synthesized and characterized by elemental analyses, IR, ESI mass spectroscopy and cyclic voltammetric studies. Single crystal X-ray study on 2 reveals that the manganese(III) atom is octahedrally coordinated under O3N3 donor environment with oxygen atom of coordinated methyl alcohol and nitrogen (N2) atom of (N′,N′-dimethyl) ethyl side arm of the ONNO donor ligand (H2L2) occupying the axial sites while the two oxygen atoms (O1 and O2), tripodal nitrogen atom (N1) from bis(phenolate) ligand and one nitrogen atom (N3) from azide co-ligand occupying the equatorial plane. Both the complexes show irreversible cyclic voltammeric responses. Steady-state fluorescence studies on the ligands H2L1 and H2L2 and their corresponding complexes reveal significant differences in the fluorescence pattern (broadening of the band due to complexation) and in the fluorescence yield (at the same OD) establishing the complexation process.

IPC Code: Int. Cl.8 C07F13/00

 

Indian Journal of Chemistry

Vol. 46A, July 2007, pp. 1063-1068

 

Characterization of novel diorganotin(IV) complexes with O,N,O donor ligand derived from carbohydrazide: X-ray crystal structure of [Ph2Sn(H2CBS)]

M A Affan*, Y Z Liew, Fasihuddin B Ahmad, Mustaffa B Shamsuddin & Bohari M Yamin

Received 16 June 2006; revised 7 June 2007

A new series of diorganotin(IV) complexes has been synthesized by the reaction of R2SnCl2 (R = Me, Bu and Ph) with O,N,O-tridentate carbohydrazone ligand derived from carbohydrazide. Three diorganotin(IV) complexes of carbohydrazone-bis(salicylaldehyde) ligand [H4CBS, (1)] with R2SnCl2 have been synthesized by refluxing in the presence of base in 1:2:1 molar ratio (metal:base:ligand). All the complexes (2-4) have been characterized by different physico-chemical techniques like molar conductivity measurements, elemental analyses, UV-visible, IR and 1H NMR spectral studies. All complexes (2-4) are non electrolytic in nature. Among them, diphenyltin(IV) complex (4) has also been characterized by X-ray crystallography diffraction analyses. In the solid state, the carbohydrazone ligand (1) exists as the keto tautomer. But in solution in the presence of base and organotin(IV) chloride(s), it is converted to the enol tautomer and is coordinated to the tin atom in its deprotonated enolate form. X-ray crystallographic analysis shows that the diphenyltin(IV) complex, [Ph2Sn(H2CBS)] (4), is five-coordinate and has a distorted trigonal-bipyramidal geometry with the ligand coordinated to the tin(IV) as a tridentate dinegative fashion through its phenolic-O, enolic-O and imine-N atoms. The general bond length order is: oxo < phenolato < enolato. The Sn-O (enolato) bond is longer than Sn-O (phenolato) bond by ~0.095 Å and is identical with Sn-O (carboxylate) bond. The crystal of [Ph2Sn(H2CBS)] (4) is triclinic with space group P-1 with a = 8.514(2)Å, b = 12.505(3)Å, c = 12.794(4)Å, a = 105.169(4)°, b = 107.639(4)°, g = 96.232(4)°, V = 1226.5(6) Å3, Z = 1 and Dcalc = 1.541 mg/m3. The IR, UV and 1H NMR data are consistent with all the diorganotin(IV) derivatives having similar geometry.

IPC Code: Int. Cl8 C07F7/22

 

Indian Journal of Chemistry

Vol. 46A, July 1007, pp. 1069-1074

 

New multi-site phase transfer catalyst for the addition of dichlorocarbene to olefins

K Shanmugan* & T Balakrishnan

Received 28 February 2007; revised 31 May 2007

Three step synthesis of a new, water-soluble multi-site phase transfer catalyst (MPTC-I), viz., a,a1,a11-tris(triethyl ammonium methylene bromide) b-hydroxy ethyl benzene is described. The potentiality of MPTC-I is demonstrated by studying kinetic aspects of the reactions, viz. dichlorocarbene addition to styrene, a-methyl styrene and trans-stilbene.

IPC Code: Int. Cl.8 B01J31/22

 

Indian Journal of Chemistry

Vol. 46A, July 2007, pp. 1075-1080

 

Studies on the middle phase microemulsion of alkyl polyglucoside

Jinling Chai*, Xiaodeng Yang, Yanhong Gao & Changju Wu

Received 14 June 2006; revised 28 May 2007

The middle phase microemulsions of alkyl polyglucosides (APG) C8G1.46, C10G1.46, C12G1.46, C8/10G1.31 and C12/14G1.43 have been studied with the alcohol concentration scanning phase diagram. The results show that in the quaternary system of APG/alcohol/alkane/water, the increase in the alcohol concentration causes a series of phase inversion Winsor I (2) →III(3) →II(). The order of the alcohol width and the minimum alcohol concentration needed to form middle phase microemulsion is: C8G1.46>C8/10G1.31>C10G1.46>C12G1.46>C12/14G1.43. Along with the increase in APG concentrations, the minimum alcohol concentrations increase, but that for unit APG, the concentrations decrease. The alcohol width increases first and then decreases, but that for per gram of APG decreases monotonously. The longer the alcohol hydrocarbon chain, the smaller both the alcohol width and the minimum alcohol concentration to form middle phase microemulsion, but the larger the solubilizing power. With the increase in NaCl concentrations, the minimum alcohol concentration decreases, but the alcohol width is nearly unchanged. This may be explained by “salting-out” effect. The effect of alkanes is different from that of NaCl concentrations; the minimum alcohol concentration is nearly the same, but the alcohol width increases as the alkane hydrocarbon chain length increases.

 

Indian Journal of Chemistry

Vol. 46A, July 2007, pp. 1081-1089

 

Autoprotolysis constants of ethylene glycol in isodielectric mixtures of ethylene glycol and N, N-dimethyl formamide at 298.15 K and the related Gibbs energies of transfer

B K Dolui, S K Bhattacharya* & K K Kundu*

Received 26 December 2006; revised 30 May 2007

Autoprotolysis constants (Ks) of ethylene glycol (EgOH) have been determined in the isodielectric mixtures of protic ethylene glycol and dipolar aprotic N,N-dimethyl formamide (20, 40 and 60 wt% DMF) at 298.15 K from emf measurements of cells comprising glass GE (H+) and Ag-AgCl electrodes. Transfer Gibbs energies of glycoxide ion (EgO-), DG0t (EgO-) have been evaluated therefrom using literature values of transfer Gibbs energies of H+, DG0t (H+) based on TATB assumption. These are explained in the light of ion-solvent interactions as guided by physicochemical properties of the solvents. The results show that while the acidity of EgOH + DMF mixed solvents decreases with co-solvent due to the increased aproticity and anionophobicity of the cosolvent molecules, the basicity decreases due to the amalgamated effects of increased aproticity as well as increased protophilicity of DMF.

 

Indian Journal of Chemistry

Vol. 46A, July 2007, pp. 1090-1094

 

Oxidation of hexacyanoferrate(II) by peroxodisulphate in aqueousperchloric acid¾A kinetic and mechanistic study

S A Chimatadar, S V Madawale, K A Thabaj & S T Nandibewoor*

Received 26 June 2006; revised 16 May 2007

The kinetics of the reaction between hexacyanoferrate(II) and peroxodisulphate has been studied spectroscopically in perchloric acid. The reaction is first order each in peroxodisulphate and hexacyanoferrate(II) concentrations. Increase in perchloric acid concentration increases the reaction rate. The order with respect to perchloric acid concentration is less than unity. The active species of hexacyanoferrate(II) and peroxodisulphate are HFe(CN)63- and S2O82- respectively. A suitable mechanism is proposed for the studied reaction.  The thermodynamic quantities with respect to the first step and the activation parameters with respect to the slow step of the mechanism have been calculated. Numerical simulation with this mechanism agrees well with the experimental results.

IPC Code: Int. Cl.8 C07B33/00

 

Indian Journal of Chemistry

Vol. 46A, July 2007, pp. 1095-1100

 

Fluorescence and absorption studies on the selective recognition of iodide by lower rim 1,3-bis(aminoethoxy)-p-t-butyl-calix[4]arene derivative

Roymon Joseph, Ankur Gupta, Amjad Ali & Chebrolu P Rao*

Received 25 January 2007; revised 4 June 2007

Lower rim 1,3-bis(aminoethoxy)-p-t-butyl-calix[4]arene derivative (L) has been subjected to fluorescence and absorption studies to evaluate its utility to recognize halides. This derivative has been found to be selective towards iodide, immaterial of its counter cation as well as the presence of other halide ions. Combining this data with that of the negative ion mass spectrometry and 1H NMR spectra, an arene cavity bound iodide species is proposed.

 

Indian Journal of Chemistry

Vol. 46A, July 2007, pp. 1101-1104

 

Determination of the product yield of SO molecules formed by the reaction of H atom with SO2 at high temperatures

Yoshinori Murakami*, Shouichi Onishi &Nobuyuki Fujii

Received 15 September 2006; rerevised 16 May 2007

The product yield of SO molecules by the reaction H + SO2 has been investigated by monitoring the molecular absorptionof SO molecules at 151 nm behind the reflected shock of C2H5I / SO2 / Ar mixtures by comparing the intensity of SO absorption using thermal decomposition of the SO2 system. It has been found that the product yield of SO is 40 – 60%. It is suggested thatH + SO2 → OH + SO is one of the major pathways for the reaction of H atoms with SO2 at temperatures above 1400 K.

 

Indian Journal of Chemistry

Vol. 46A, July 2007, pp. 1105-1108

 

Unsymmetrically substituted organotin (IV) N-alkyl, N-hydroxyethyl dithiocarbamates: Synthesis and spectral aspects

S K Srivastava*, H Pandey & R Sharma

Received 5 December 2006; revised 28 May 2007

Unsymmetrically substituted triphenyltin(IV) N-alkyl, N-hydroxyethyl dithiocarbamates, [(C6H5)3SnS(S)CN(R) CH2CH2OH] [R=CH3 (1), C2H5 (2)], diphenyltin(IV) bis(N-alkyl, N-hydroxyethyl dithiocarbamates), [(C6H5)2Sn{S(S)CN(R)-CH2CH2OH}2], [R=CH3 (3), C2H5 (4)] and chlorodiphenyltin(IV) N-alkyl, N-hydroxyethyl dithiocarbamates, [(C6H5)2Sn(Cl)S (S)CN(R)CH2CH2OH] [R=CH3 (5), C2H5 (6)] have been synthesized and characterized on the basis of elemental analysis and spectral data (FAB mass, UV, IR, 1H, 13C and 119Sn NMR). The Sn atom exhibits 5- and 6-coordination in the complexes.

IPC Code: Int. Cl.8 C07F7/22

 

Indian Journal of Chemistry

Vol. 46A, July 2007, pp. 1109-1112

 

Synthesis, spectroscopic and electrochemical studies of novel transition metal complexes with N,N'-bis(2-hydroxynaphthalin-1-carbaldehydene)-1,3-bis-(o-aminophenoxy)propane

Hamdi Temel*, Salih İlhan, Mehmet Aslanoğlu & Hüseyin Alp

Received 9 March 2007; revised 4 June 2007

A novel Schiff base obtained by the reaction of 1,3-bis-(o-aminophenoxy)propane and 2-hydroxynaphthalin-1-carbaldehyde, forms complexes with Co(II), Cu(II) and Ni(II). The Schiff base ligand and its metal complexes have been characterized by elemental analysis, microanalytical data, magnetic measurements, UV-visible, 1H NMR, 13C NMR and IR-spectra as well as conductance measurements. Electrochemical data show that NiL and CuL complexes undergo metal based quasi-reversible one-electron redox processes. However, metal complexes also exhibit ligand based irreversible redox waves. The electrochemical results also indicate that the electron transfer rate is higher for NiL complex than the CuL complex. Voltammetric data reveal easier electron donor properties for the NiL complex.

IPC Code: Int. Cl.8 C07C251/02; C07F1/08; C07F15/04; C07F15/06

 

Indian Journal of Chemistry

Vol. 46A, July 2007, pp. 1113-1115

 

Synthesis and characterization of new complexes formed by insertion of carbon disulphide in RuL3Cl3 (L=PPh3 and AsPh3)

Pradip K Gogoi*, Geetika Borah*, Nayanmoni Bharali & Diganta Saikia

Received 12 November 2006; revised 3 May 2007

Reaction of RuL3Cl3 (L=PPh3 and AsPh3) with stoichiometric amount of CS2 in ethanol-dichloromethane mixed solvent systems at room temperature yields paramagnetic complexes of the type [RuL2Cl2(S2COEt)].The complexes have been characterized by conductance, IR, electronic, ESR spectral, magnetic moment measurement and thermal data as well as by elemental analysis. The appearance of three g-values in the ESR spectra reveal a highly distorted octahedral environment around ruthenium(III) ion with one bidented EtOCS2ˉ ligand.

IPC Code: Int. Cl.8 C07F15/00

 

Indian Journal of Chemistry

Vol. 46A, July 2007, pp. 1116-1120

 

Inhibition effect of Brij-35 on the rate of oxidation of ascorbic acid by hexacyanoferrate(III) in acidic medium: A kinetic study

Ratna Shukla & Santosh K Upadhyay*

Received 23 February 2007; revised 8 June 2007

The effect of non-ionic surfactant, i.e. Brij-35, polyoxyethylene(23)laurylether, on the rate of oxidation of ascorbic acid by hexacyanoferrate(III) in acidic (HClO4) medium has been studied spectrophotometrically in the temperature range 30-50°C. The rate of oxidation is inhibited in presence of Brij-35 even below the critical micelle concentration (CMC) of the surfactant. A mechanism of oxidation in presence of the surfactant is proposed and discussed. The binding parameters between the surfactant and ascorbic acid have been evaluated using Menger and Portnoy’s  model reported for micellar catalysis/inhibition.

IPC Code: Int. Cl.8 C07B33/00

 

Indian Journal of Chemistry

Vol. 46A, July. 2007, pp. 1121-1124

 

A pulse polarographic method for the analysis of zinc dithiocarbamates

D K Sharma*, Satish Kumar, Chetan Chauhan & Atul Gupta

Received 6 December 2006; revised 30 April 2007

An extremely sensitive pulse polarographic method for the determination of zinc dimethyldithiocarbamate (an agricultural fungicide) and zinc di-n-pentyldithiocarbamate (a petroleum additive), has been developed based on the reaction of their dithiocarbamate moiety with copper(II) perchlorate in acetonitrile medium. Well defined diffusion-controlled peaks are observed at –140 mV and –130 mV (vs SCE) for zinc dimethyldithiocarbamate and zinc di-n-pentyldithiocarbamate respectively. The peaks shows approximately four-fold higher sensitivity than that obtained by pulse polarography of the zinc dithiocarbamate alone. A linear relationship is obtained between concentration of the zinc dithiocarbamate [added to copper(II)] and peak current. Using cyclic voltammetry, a probable mechanism for the zinc dithiocarbamate-copper(II) reaction has been proposed.

IPC Code: G01N27/00