Indian Journal of Chemistry

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

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CODEN: ICACEC; ISSN: 0376-4710 (Print), 0975-0975 (Online)

 

 

VOLUME 52A

NUMBER 11

NOVEMBER 2013

 

CONTENTS

 

 

1377

 

Unusual salting effects in ionic liquid solutions

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Raju Nanda & Anil Kumar*

 

 

 

Salting behavior in water is altered in the presence of ionic liquids. In presence of ionic liquids with higher alkyl chain, salting-in agents display unusual fall and rise in the viscosity of the systems. No change in the behavior of the salting-out agents is noted in these ionic liquids.

 

 

 

 

1383

 

Preparation and characterization of iron-polypyrrole-carbon composite for use as methanol tolerant cathode material in direct methanol fuel cells

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Madhu, C S Sharma & R N Singh*

 

 

 

Electrochemical studies carried out with the iron-polypyrrole-carbon composite catalyst in Ar- and O2- saturated 0.5 M H2SO4 with and without 1 M CH3OH at 25 °C show that the catalyst iss oxygen reduction reaction active and stable, and does not oxidize methanol.

 

 

 

 

1391

 

Volumetric and acoustic studies of binary liquid mixtures of alkoxypropanols with ethyl acetoacetate in the temperature range (288.15 - 308.15) K

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Amalendu Pal*, Harsh Kumar, Ritu Maan &
Harish Kumar Sharma

 

 

 

Excess molar volumes for the alkoxypropanols+ethyl acetoacetate  binary mixtures are positive, indicating that the binary
mixtures expand upon mixing the pure components and molecules of pure components interact weakly in solution.
On increasing the chain length of the alkoxypropanol, the interactions become weaker.

 

 

 

 

Notes

 

1400

 

Palladium(II) complex of phosphinic amide, [Pd(Ph2P(O)CH2NPh)2], and its catalytic investigation towards Suzuki-Miyaura cross-coupling reactions

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Sk Md Ibrahim, Chelladurai Ganesamoorthy &
Maravanji S Balakrishna
*

 

 

 

Synthesis and Suzuki-Miyaura cross-coupling reaction of the complex [Pd(Ph2P(O)Ch2NPh)2] is reported. Reaction of aryl halides with phenylboronic acid using [Pd(Ph2P(O)CH2NPh)2] as catalyst gave moderate (35-55%) to high yields (100%) of the coupled product.

 

 

IC 3762_GA.tif

 

 

 

1404

 

Syntheses, structures and properties of cadmium(II) halide complexes containing tridentate Schiff bases

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subhasish Kundu, Subhasis Roy, Kishalay Bhar,
Dipu Sutradhar, Partha Mitra &
Barindra Kumar Ghosh
*

 

 

 

Pentacoordinated cadmium(II) halide complexes of two closely related tridentate Schiff bases are synthesised and X-ray crystallographically characterized. Chelation behavior of the Schiff bases and terminal motif of halides are seen in each case. Intermolecular C-H…Br hydrogen bonds, p…p and C-H…p interactions promote different dimensionalities. The complexes display intraligand (p-p*) fluorescence in DMF solutions at room temperature.

 

 

 

 

1411

 

Thermodynamic and kinetic investigations on the reaction of methanethiol with oxygen atom

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Si Wei-Jinag, Zhuo Shu-Ping* & Zhou Zi-Yan

 

 

 

Thermodynamic and kinetic parameters of two channels for the CH3SH+O reaction have been investigated using the statistic theory and Eyring transition state theory with Wigner correction at 200-200 K. While both channels are spontaneous and exothermic and are thermodynamically favoured at low temperature and kinetically favoured at high temperature,
channel I has an advantage over channel II.

 

 

 

 

1416

 

Heterogeneous photo-Fenton like degradation of rhodamine B using copper loaded bentonite and H2O2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Kiran Chanderia, Sangeeta Kalal, Jyoti Sharma,
Noopur Ameta & Pinki B Punjabi
*

 

 

 

Photo-Fenton like degradation of rhodamine B using copper loaded bentonite and hydrogen peroxide as a novel catalytic system shows that the catalyst mineralizes the dye with aphotodegradation efficiency of 67.92% in the visible light.

 

 

 

 

 

 

Authors for correspondence are indicated by (*)

 

Indian Journal of Chemistry

Vol. 52A, November 2013, pp. 1377-1382

 

 

Unusual salting effects in ionic liquid solutions

Raju Nanda & Anil Kumar*

Physical & Materials Chemistry Division, National Chemical Laboratory, Pune 411 008, India

Email: a.kumar@ncl.res.in

Received 2 September 2013; revised and accepted 3 October 2013

Unusual salting effects of salting-out agents like LiCl and NaCl and salting-in agents like LiClO4 and NaClO4 in ionic liquid solutions are reported. It is observed that the salting behavior in water can be altered in the presence of ionic liquids. It is demonstrated that the salting-in agents in the presence of the ionic liquids with higher alkyl chain can display unusual fall and rise in the viscosity of the systems. On the other hand, no change in the behavior of the salting-out agents is noted in these ionic liquids. A tentative explanation is proposed for the observed viscosity data in these systems.

Keywords: Ionic liquids, Salting effects, Viscosity, Cationic ring

 

Indian Journal of Chemistry

Vol. 52A, November 2013, pp. 1383-1390

 

 

Preparation and characterization of iron-polypyrrole-carbon composite for use as methanol tolerant cathode material in direct methanol fuel cells

Madhu, C S Sharma & R N Singh*

Department of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi 221 005, India

Email: rnsbhu@rediffmail.com

Received 8 April 2013; revised and accepted 14 October 2013

Novel carbon supported iron-polypyrrole (30 wt% Fe-PPy-C) composite catalyst has been prepared by using a chemical polymerization method and investigated as electrocatalyst for the oxygen reduction reaction in 0.5 M H2SO4 at 25 °C. Structural and electrochemical characterizations of the catalyst have been carried out by IR, XRD, SEM, cyclic and linear sweep voltammetry, chronoamperometry and electrochemical impedance spectroscopy. Electrochemical studies have been performed in Ar- and O2- saturated 0.5 M H2SO4 with and without 1 M CH3OH at 25 °C. The study shows that the composite catalyst is oxygen reduction reaction active and stable, and does not oxidize methanol and hence can be used as an efficient methanol tolerant cathode material in direct methanol fuel cells.

Keywords: Catalysts, Composites, Iron polypyrrole carbon composite, Oxygen reduction reaction,
Methanol tolerant cathode material, Fuel cells, Direct methanol fuel cells

 

 

 

Indian Journal of Chemistry

Vol. 52A, November 2013, pp. 1391-1399

 

 

Volumetric and acoustic studies of binary liquid mixtures of alkoxypropanols with ethyl acetoacetate in the temperature range (288.15 - 308.15) K

 

Amalendu Pala, *, Harsh Kumarb, Ritu Maanc & Harish Kumar Sharmac

aDepartment of Chemistry, Kurukshetra University, Kurukshetra 136 119, Haryana, India

bDepartment of Chemistry, Dr BR Ambedkar National Institute of Technology, Jalandhar 144 011, Punjab, India

cDepartment of Chemistry, MM University, Mullana, Ambala, Haryana, India

Email: palchem@sify.com

Received 13 May 2013; revised and accepted 14 October 2013

Densities and speeds of sound for the binary liquid mixtures of propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, and propylene glycol monobutyl ether with ethyl acetoacetate, have been measured over the entire composition range at temperatures T = (288.15, 293.15, 298.15, 303.15, and 308.15) K and atmospheric pressure. The density values have been used to calculate excess molar volumes (), while speeds of sound data have been used to calculate deviation in isentropic compressibility
(). The changes in these properties with the composition and temperature have been discussed in terms of molecular interactions existing in the solution phase.

Keywords: Density, Ultrasonic speed, Binary mixtures, Alkoxypropanol, Ethyl acetoacetate

 

Indian Journal of Chemistry

Vol. 52A, November 2013, pp. 1400-1403

 

 

Palladium(II) complex of phosphinic amide, [Pd(Ph2P(O)CH2NPh)2], and its
catalytic investigation towards Suzuki-Miyaura cross-coupling reactions

Sk Md Ibrahim, Chelladurai Ganesamoorthy & Maravanji S Balakrishna*

Phosphorus Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India

Email: krishna@chem.iitb.ac.in

Received 18 June 2013; revised and accepted 28 September 2013

The reaction between aniline and chlorodiphenylphosphine in 2:1 molar ratio afforded the aminophosphine C6H5NHPPh2 (1) which on subsequent treatment with paraformaldehyde produced the methylene inserted product, Ph2P(O)CH2NHPh (2). Treatment of (2) with Pd(OAc)2 in 2:1 molar ratio produced the complex [Pd(Ph2P(O)CH2NPh)2] (3), which has been characterized by various spectroscopic and microanalysis data. The catalytic activity of complex (3) has been investigated in Suzuki-Miyaura cross-coupling reactions. The reactions of various aryl halides with phenylboronic acid using (3) as a catalyst gave moderate (35–55%) to high yields (100%) of coupled products.

Keywords: Aminophosphines, Aryl halides, Phosphinic amide, Palladium, Cross-coupling reactions,
Suzuki-Miyaura cross-coupling reactions, Catalytic activity

 

Indian Journal of Chemistry

Vol. 52A, November 2013, pp. 1404-1410

 

 

Syntheses, structures and properties of cadmium(II) halide complexes

containing tridentate Schiff bases

Subhasish Kundua, Subhasis Roya, Kishalay Bhara, Dipu Sutradhara, Partha Mitrab & Barindra Kumar Ghosha, *

aDepartment of Chemistry, The University of Burdwan, Burdwan 713 104, India

bDepartment of Inorganic Chemistry, Indian Association for the Cultivation of Science, Kolkata 700 032, India

Email: barin_1@yahoo.co.uk

Received 22 January 2013; revised and accepted 25 September 2013

Three neutral mononuclear complexes of the type [Cd(L1)I2] (1) [L1 = (N,N-diethyl,N'-(pyridin-2-yl)formylidene)ethane-1,2-diamine] and [Cd(L2)X2] [L2 = (N,N-diethyl,N'-(pyridin-2-yl)benzylidene)ethane-1,2-diamine; X = Br­- (2), I- (3)] are isolated using one-pot reactions of cadmium(II) halides and tridentate Schiff bases (L1 and L2) in a 1:1 molar ratio in MeOH solutions at room temperature. The compounds are characterized by elemental analyses and spectroscopic and other physicochemical data. Single-crystal X-ray diffraction analyses of (1)-(3) show that cadmium(II) center in each complex adopts a distorted square pyramidal geometry bound by three N atoms of L1/L2 and two terminal halides. Intermolecular p…p interactions in (1), cooperative C-H…Br hydrogen bonds and C-H…p interactions in (2) and C-H…p interactions in (3) lead to different crystalline architectures. Thermogravimetric analyses show that the compounds have reasonable thermal stabilities. The complexes display ligand-centered π–π* fluorescence in DMF solutions at room temperature.

Keywords: Coordination chemistry, Cadmium(II), Schiff bases, Halides, Crystal structures, Luminescence

 

Indian Journal of Chemistry

Vol. 52A, November 2013, pp. 1411-1415

 

 

Thermodynamic and kinetic investigations on the reaction of

methanethiol with oxygen atom

Si Wei-Jinag, Zhuo Shu-Ping * & Zhou Zi-Yan

School of Chemical Engineering, Shandong University of Technology, Zibo 255049, PR China

Email: zhuosp@sdut.edu.cn

Received 1 April 2013; revised and accepted 3 October 2013

The mechanism of the reaction of CH3SH+O has been studied by employing density functional theory at the B3LYP/6-311++G** level. Two reaction channels, viz., the O-attack of the H atom of -SH group (R1), and, the O-attack of the C atom of –CH3 group (R2) have been found. Optimized geometries, frequencies and energies of the stationary points are calculated at the B3LYP/6-311++G** level of theory. The thermodynamic data and the equilibrium constants of the two channels for CH3SH+O reaction are calculated using the statistic theory at 200-2000 K. On the basis of Eyring transition state theory with Wigner correction, the activation parameters, the rate constants and frequency factors of the two reaction channels are obtained in the range of 200 to 2000 K. The results show that both channels of the reaction CH3SH+O are spontaneous and exothermic and that the entropy decreases in the range 200-2000 K. Both channels of this reaction are thermodynamically dominant at low temperatures and kinetically favored at higher temperatures. Although the two channels are competitive over the entire temperature range, channel I (R1) has both thermodynamic and kinetic advantage over channel II (R2),

and is the major reaction pathway of CH3SH+O at 200-2000 K.

Keywords: Theoretical chemistry, Density functional calculations, Thermodynamics, Kinetics, Methanethiol, Mercaptan

 

 

Indian Journal of Chemistry

Vol. 52A, November 2013, pp. 1416-1420

 

 

Heterogeneous photo-Fenton like degradation of rhodamine

B using copper loaded bentonite and H2O2

Kiran Chanderia, Sangeeta Kalal, Jyoti Sharma, Noopur Ameta & Pinki B Punjabi*

Photochemistry Laboratory, Department of Chemistry, University College of Science, M L Sukhadia University,
Udaipur 313 002, India

Email: pb_punjabi@yahoo.com

Received 6 February 2013; revised and accepted 9 October 2013

Photo-Fenton like degradation of rhodamine B using copper loaded bentonite and hydrogen peroxide is reported. The catalyst has been prepared by loading copper ions on bentonite by wet impregnation method using Na2CO3, Cu(NO3)2.3H2O and bentonite clay. On photo-Fenton treatment, the dye mineralizes into smaller ions like CO32-, NO3-, NO2- etc. The photodegradation efficiency of the catalyst for the rhodamine B dye is found to be 67.92%. Under optimal conditions, the rate constant k is 3.72 Χ 10-4s-1. A tentative mechanism involving •OH radical as an oxidant in degradation process is proposed. Involvement of •OH radicals as an active oxidizing agent is confirmed by the drastic reduction in rate of reaction in presence of isopropanol and butylated hydroxy toluene as radical scavengers. The reduction in reaction rate is higher with butylated hydroxy toluene as compared with isopropanol as the radical scavengers.

Keywords: Degradation, Photodegradation, Photo-fenton reaction,     Photo catalyst, Dye degradation, Rhodamine B, Bentonite