J. Serb. Chem. Soc. 74 (12) 1335–1357 (2009)
UDC 547–32:547.437’631:544–145.55:541.42; JSCS–3922; doi: 10.2298/JSC0912335U; Author’s Review

Author’s Review

The study of linear solvation energy relationship for the reactivity of carboxylic acids with diazodiphenylmethane in protic and aprotic solvents

GORDANA S. UŠĆUMLIĆ and JASMINA B. NIKOLIĆ

Department of Organic Chemistry, Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, P.O. Box 3505, 11120 Belgrade, Serbia

(Received 15 June 2009)

Solvent effects on the reactivity of cycloalkenecarboxylic, cycloalkeneacetic, 2-substituted cyclohex-1-enecarboxylic, 2-substituted benzoic, 2-substituted cyclohex-1-eneacetic, 2-substituted phenylacetic, 2-phenylcyclohex-1-enecarboxylic, 2-phenylbenzoic and 2-phenylacrylic acids with diazodiphenylmethane (DDM) were investigated. In order to explain the kinetic results through solvent effects, the second-order rate constants for the reaction of the exAMined acids with DDM were correlated using the KAMlet–Taft solvatochromic equation. The correlations of the kinetic data were realized by means of multiple linear regression analysis and the solvent effects on the reaction rates were analyzed in terms of the contributions of the initial and the transition state. The signs of the equation coefficients support the proposed mechanism. Solvation models for all the investigated acids are suggested. The quantitative relationship between the molecular structure and the chemical reactivity is also discussed.

Keywords: carboxylic acids; linear solvation energy relationship; diazodiphenylmethane; aprotic solvents; protic solvents.

J. Serb. Chem. Soc. 74 (12) 1359–1370 (2009)
UDC 633.71–32+547.437’631:544–145.55; JSCS–3923; doi: 10.2298/JSC0912359D; Original scientific paper

Effects of solvent and structure on the reactivity of 6-substituted nicotinic acids with diazodiphenylmethane in aprotic solvents
SAŠA Ž. DRMANIĆ, ALEKSANDAR D. MARINKOVIĆ and BRATISLAV Ž. JOVANOVIĆ
Department of Organic Chemistry, Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, P.O. Box 3505, 11120 Belgrade, Serbia

(Received 26 May, revised 18 August 2009)

The rate constants for the reactions of diazodiphenylmethane (DDM) with 6-substituted nicotinic acids in aprotic solvents at 30 °C were determined. The obtained second order rate constants in aprotic solvents, together with literature data for benzoic and nicotinic acids in protic solvents, were used for the calculation of solvent effects, employing the KAMlet-Taft solvatochromic equation (linear solvation energy relationship – LSER) in the form: log k = log k₀ + sp* + aa + bb. The correlations of the kinetic data were performed by means of multiple linear regression analysis taking appropriate solvent parAMeters. The sign of the equation coefficients (s, a and b) were in agreement with the postulated reaction mechanism, and the mode of the solvent influences on the reaction rate is discussed based on the correlation results. A similar contribution of the non-specific solvent effect and electrophilic solvation was observed for all acids, while the highest contribution of nucleophilic solvation was influenced by their high acidity. Correlation analysis of the rate data with substituent s_p parAMeters in an appropriate solvent using the HAMmett equation was also performed. The substituent effect on the acid reactivity was higher in aprotic solvents of higher dipolarity/polarizability. The mode of the transmission of the substituent effect is discussed in light of the contribution of solute–solvent interaction on the acid reactivity.

Keywords: pyridine carboxylic acids; diazodiphenylmethane; rate constants; solvatochromic parAMeters; aprotic solvents.

J. Serb. Chem. Soc. 74 (12) 1371–1376 (2009)
UDC 547.77+547.556.8+547.291:542.913; JSCS–3924; doi: 10.2298/JSC0912371M; Short communication

Short communication

Synthesis and characterization of a series of 1,3,5-trisubstituted-2-pyrazolines derivatives using methanoic acid under thermal condition
BEHROOZ MALEKI, DAVOOD AZARIFAR*, MONA KHODAVERDIAN MOGHADDAM, SEYEDEH FATEMEH HOJATI, MOSTAFA GHOLIZADEH and HAFEZEH SALEHABADI
Department of Chemistry, Sabzevar Tarbiat Moallem University, Sabzevar-397, Khorasan, Iran

*Department of Chemistry, Bu-Ali Sina University, HAMadan-65178, Iran

(Received 7 October, revised 28 October 2009)

An efficient and practical synthesis of 1,3,5-trisubstituted 2-pyrazoline structures was achieved through cyclization of phenylhydrazine with a,b-unsaturated ketones (chalcones) using methanoic acid (formic acid) as catalyst under thermal condition.

Keywords: 1,3,5-trisubstituted-2-pyrazoline; phenylhydrazine; chalcone; methanoic acid; heterocyclic synthesis.

J. Serb. Chem. Soc. 74 (12) 1377–1387 (2009)

UDC 547.758+542.913:57-188:615.281; JSCS–3925; doi: 10.2298/JSC0912377R; Original scientific paper

Synthesis and biological activities of some indoline derivatives
MILIND A. RODE, SAHEBRAO S. RINDHE and BHAUSAHEB K. KARALE*

Department of Chemistry, New Arts, Commerce and Science College, Ahmednagar-414001, India

*Department of Chemistry, Radhabai Kale Mahila Mahavidyalaya, Ahmednagar-414001, India

(Received 14 April 2009)

The reaction of indoline with a substituted benzoyl chloride in the presence of K₂CO₃ in THF gave compound 4. Compound 4 was subjected to chlorosulphonation to obtain compound 5. Condensation of aromatic AMines with compound 5 led to the synthesis of indoline derivatives 6(a–f). Similarly, 5-nitroindoline was treated with a substituted benzoyl chloride to obtain the nitro compound 9, which was reduced using stannous chloride and reacted further with aromatic sulphonyl chloride to obtain the indoline derivatives 11(a–e). These compounds were tested for antibacterial, anti-tuberculosis and antifungal activity. Some of them showed very good activity against some grAM-positive and grAM negative bacteria, fungal strains and also Mycobacterium tuberculosis. All of the synthesized compounds were subjected to antioxidant activity testing using the in vitro DPPH assay and most of them showed very good activity.

Keywords: indoline; antioxidant activity; antifungal; anti-tuberculosis and antibacterial activity.

J. Serb. Chem. Soc. 74 (12) 1389–1399 (2009)
UDC 634.441:547.972.2/.3:615.281–188; JSCS–3926; doi: 10.2298/JSC0912389K; Original scientific paper

J. Serb. Chem. Soc. 74 (12) 1401–1411 (2009)

J. Serb. Chem. Soc. 74 (12) 1413–1422 (2009)

UDC 546.763’712’732.004.12:547.497.1:615.28–188; JSCS–3928; doi: 10.2298/JSC0912413C; Original scientific paper

J. Serb. Chem. Soc. 74 (12) 1423–1428 (2009)

UDC 512.533.2:517.518.1:517.548.58:519.233.2; JSCS–3929, doi: 10.2298/JSC0912423L; Original scientific paper

Obtaining the Varshni potential function using the 2-body Kaxiras–Pandey parAMeters

TEIK-CHENG LIM

School of Science and Technology, SIM University, 535A Clementi Road, S 599490, Republic of Singapore

(Received 23 June 2009)

A generalized version of the Varshni potential function was adopted by Kaxiras and Pandey for describing the 2-body energy portion of multi-body condensed matter. The former’s simplicity and resemblance to a Morse potential allows faster computation while the latter’s greater number of parAMeters allows better curve-fitting of spectroscopic data. This paper shows one set of parAMeter conversion from the Varshni function to the 2-body portion of the Kaxiras–Pandey function, and vice versa two sets of parAMeter conversion. The latter two sets reveal good correlation between plotted curves, and were verified by the imposition of equal energy curvatures at equilibrium and equal energy integral from equilibrium to dissociation. These parAMeter conversions can also be attained more easily by equating the product of indices (for short range) and the summation of index reciprocals (for long range).

Keywords: derivative; integral; Kaxiras–Pandey; parAMeter conversion; potential function; Varshni.

J. Serb. Chem. Soc. 74 (12) 1429–1442 (2009)

UDC 544.032.4:66.095.21.097:544.478+546.831; JSCS–3930; doi: 10.2298/JSC0912429Z; Original scientific paper

Temperature imposed textural and surface synergism affecting the isomerization activity of sulfated zirconia catalysts

ALEKSANDRA ZARUBICA, BRANISLAV JOVIĆ*, ALEKSANDAR NIKOLIĆ*, PAULA PUTANOV** and GORAN BOŠKOVIĆ

Faculty of Technology, University of Novi Sad, 21000 Novi Sad, Serbia

*Faculty of Natural Sciences and Mathematics, Department of Chemistry, University of Novi Sad, 21000 Novi Sad, Serbia

**Serbian Academy of Sciences and Arts, Knez Mihailova 10, 11000 Belgrade, Serbia

(Received 15 October, revised 29 October 2009)

Using sulfuric acid as the sulfating agent, two catalyst series were obtained from hydroxide and nitrate precursor with a sulfate loading identical to commercial sulfated hydroxide, i.e., 4.2 mass %. After calcination at 500, 600 and 700 °C, all nine sAMples had various contents of residual sulfates depending on the origin of the catalyst. Accordingly, their surface properties were different, which, together with various textural properties, govern the formation of the active phase and their catalytic activity in the n-hexane isomerization reaction. The dominant activity and yield of mainly mono-branched isomers were attained in reaction at 200 °C with a commercially sulfated zirconia catalyst calcined at 500 °C. Among the SZ catalyst series synthesized from hydroxide and nitrate, the second according to its activity profile was similar to that of the commercially sulfated one, while sAMples originating from hydroxide showed some activity only after calcination at 600 °C. This is due to the poorer textural properties of the hydroxide series, necessitating a higher calcination temperature in order to promote the simultaneous decomposition of S-containing species and their re-adsorption into the zirconia matrix following interaction and active phase formation. It seems that the tetragonal zirconia phase was not responsible for the catalytic activity but a synergistic effect of the textural properties of the sAMples and the sulfate loadings, which determine different acid strengths on the catalyst surface.

Keywords: active phase formation; calcination temperature; isomerization activity; sulfated zirconia catalyst; synergism of textural and surface properties.

J. Serb. Chem. Soc. 74 (12) 1443–1453 (2009)

UDC 541.135.5–039.26:543.552:544.478.1; JSCS–3931; doi: 10.2298/JSC0912443Y; Original scientific paper

Electrochemical detection of carbidopa using a ferrocene-modified carbon nanotube paste electrode

HALIMEH YAGHOUBIAN, HASSAN KARIMI-MALEH*, MOHAMMAD ALI KHALILZADEH* and FATEMEH KARIMI*

IslAMic Azad University, Branch of BAM, BAM, Iran

*Department of Chemistry, IslAMic Azad University, Qaemshahr, Iran

(Received 1 May, revised 6 August 2009)

A chemically modified carbon paste electrode (MCPE) containing ferrocene (FC) and carbon nanotubes (CNT) was constructed. The electrochemical behavior and stability of the MCPE were investigated by cyclic voltAMmetry. The electrocatalytic activity of the MCPE was investigated and it showed good characteristics for the oxidation of carbidopa (CD) in phosphate buffer solution (PBS). A linear concentration range of 5 to 600 μM CD, with a detection limit of 3.6±0.17 μM CD, was obtained. The diffusion coefficient of CD and the transfer coefficient (a) were also determined. The MCPE showed good reproducibility, remarkable long-term stability and especially good surface renewability by simple mechanical polishing. The results showed that this electrode could be used as an electrochemical sensor for the determination of CD in real sAMples, such as urine sAMples.

Keywords: carbidopa; ferrocene; carbon nanotube; modified electrode; voltAMmetry.

J. Serb. Chem. Soc. 74 (12) 1455–1465 (2009)

UDC 547–327:543.4/.5:547.826.2/.3:632.951; JSCS–3932 doi: 10.2298/JSC0912455G; Original scientific paper

A rapid spectrophotometric determination of imidacloprid in selected commercial formulations in the presence of 6-chloronicotinic acid

VALÉRIA J. GUZSVÁNY, ZSIGMOND J. PAPP, SANJA D. LAZIĆ*, FERENC F. GAÁL, LUKA J. BJELICA and BILJANA F. ABRAMOVIĆ

Department of Chemistry, Biochemistry and Environmental Protection, Faculty of Sciences, University of Novi Sad, Trg D. Obradovića 3, 21000 Novi Sad, Serbia

*Faculty of Agriculture, University of Novi Sad, Trg D. Obradovića 8, 21000 Novi Sad, Serbia

(Received 15 October 2009)

A simple first-order derivative spectrophotometric method was developed for the simultaneous determination of imidacloprid and 6-chloronicotinic acid (6-CNA). By using the zero-crossing approach, imidacloprid was determined at 249.0 nm and 6-CNA at 236.0 nm with detection limits of 0.32 and 0.17 µg mL-1, respectively, and relative standard deviations not exceeding 1.2 % in the case of model systems. The proposed method was applied for the determination of imidacloprid and 6-CNA in commercial formulations. A conventional spectrophotometric method (at 270 nm) was also employed for the determination of the content of imidacloprid in the sAMe commercial formulations. The results of the developed spectrophotometric methods were in good agreement with those obtained by the high-performance liquid chromatographic method.

Keywords: derivative spectrophotometry; imidacloprid; 6-chloronicotinic acid; insecticide formulations.

J. Serb. Chem. Soc. 74 (12) 1467–1476 (2009)

UDC 663.12:547.963.32+543.552; JSCS–3933; doi: 10.2298/JSC0912467Z; Original scientific paper

Sensitive voltAMmetric detection of yeast RNA based on its interaction with Victoria Blue B

WEILI ZHANG, XUELIANG NIU, NA ZHAO* and WEI SUN*

Department of Basic Medicine, Shandong Wanjie Medical College, Zibo 25521, P. R. China

*College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, P. R. China

(Received 7 January, revised 25 May 2009)

VoltAMmetric studies of the interaction of yeast RNA (y-RNA) with Victoria Blue B (VBB) are described in this paper. Furthermore, a linear sweep voltAMmetric method for the detection of y-RNA was established. The reaction conditions, such as acidity and AMount of buffer solution, the concentration of VBB, the reaction time and temperature, etc., were carefully investigated by second order derivative linear sweep voltAMmetry. Under the optimal conditions, the reduction peak current of VBB at –0.75 V decreased greatly after the addition of y-RNA to the solution without any shift of the reduction peak potential. Based on the decrease of the peak current, a new quantitative method for the determination of y-RNA was developed. The effects of co-existing substances on the determination were carefully investigated and three synthetic sAMples were determined with satisfactory results. The stoichiometry of the VBB–y-RNA complex was calculated by linear sweep voltAMmetry and the interaction mechanism is discussed.

Keywords: interaction; linear sweep voltAMmetry; Victoria Blue B; yeast RNA.

J. Serb. Chem. Soc. 74 (12) 1477–1489 (2009)

UDC 550.4:553.065:553.611:549.261(438); JSCS–3934; doi: 10.2298/JSC0912477P; Original scientific paper

Geochemistry of Fe³⁺ in the hydrothermal dickite from Jedlina Zdroj (Lower Silesia, Poland)

PAVLE I. PREMOVIĆ, JUSTYNA CIESIELCZUK*, BRATISLAV Ž. TODOROVIĆ**, DRAGAN M. DJORDJEVIĆ and NENAD S. KRSTIĆ

Laboratory for Geochemistry, Cosmochemistry and Astrochemistry, University of Niš, P.O. Box 224, 18000 Niš, Serbia

*Department of General Geology, Faculty of Earth Sciences, University of Silesia, Sosnowiec, Poland

**Laboratory for General Chemistry, Faculty of Technology, University of Niš, P.O. Box 79, 16000 Leskovac, Serbia

(Received 20 March, revised 20 May 2009)

Geochemical analysis for Fe was made on a representative sAMple of dickite-rich hydrothermal clay from Jedlina Zdroj. The mineralogy of the sAMple is comparatively simple, dickite being the principal component (>95 wt. % of the total sAMple), with lesser AMounts of goethite and barite. Geochemical fractionation and inductively coupled plasma–optical emission spectrometry indicated that most of the Fe (ca. 97 wt. % of the total metal) resides in the dickite. Electron spin resonance showed that some of the Fe in the dickite structure is in the form of Fe³⁺. A substantial proportion of these ions (as well as Fe) in the dickite matrix were probably contained in the original hydrothermal dickite-forming solution. From the geochemistry of Fe³⁺, it was deduced that the oxidation potential (Eh) and pH of the solution during the formation of dickite from the Jedlina Zdroj were approximately 0.45–0.95 V (highly oxygenated) and 0–4 (highly acidic), respectively.

Keywords: kaolinite; dickite; iron.

J. Serb. Chem. Soc. 74 (12) 1491–1501 (2009)

Contents of Volume 74

J. Serb. Chem. Soc. 74 (12) 1503–1509 (2009)

Subject index

J. Serb. Chem. Soc. 74 (12) 1511–1518 (2009)

Author index

End of Vol 74

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