Effect of Temperature and Solvent on Molecular Interactions of 1,2,4-Triazole Derivative

 

Dinesh R. Godhani¹*, Anand A. Jogel¹, Vishal B. Mulani¹, Anil M. Sanghani²,

Nipul B. Kukadiya¹, Jignasu P. Mehta¹

¹Physical Chemistry Division, Department of Chemistry (UGC NON-SAP and DST-FIST sponsored) Mahatma Gandhi Campus, Maharaja Krishnakumarsinhji Bhavnagar University, Bhavnagar- 364002, Gujarat, India

^2.Chemistry Department, Sir P. P. Institute of Science, Bhavnagar-364002, Gujarat, India

*Corresponding Author E-mail: drgodhani@yahoo.com

The present work describes the synthesis, characterization, thermal analysis and thermo-acoustical parameters of 5-(3-methoxyphenyl)-1-phenyl-2-((m-tolylamino)methyl)-1H-1,2,4-triazole-3(2H)-thione(MM4_a). The thermal behavior of MM4_a was studied by thermal techniques and associated kinetic parameters were evaluated according to Freeman-Carroll method. The density (ρ), viscosity (η) and ultrasonic sound velocity(U) of 1,4-Dioxane and solutions of MM4_a (0.1-0.01 M)were investigated at three different temperature (303, 308 and 313) K and atmospheric pressure. Some acoustical parameters such asadiabatic compressibility (κ_s), intermolecular free path length (L_f), Rao’s molar sound function (R_m), Van der Waals constant (b), internal pressure (π), free volume (V_f) and solvation number (S_n), entropy of activation (DS^#), pre-exponential factor (A), enthalpy of activation (DH^#) and Gibbs free energy of the decomposition (DG^#) were calculated. The results obtained were interpreted in terms of solute-solvent and solute-solute interactions.

 

 

 

INTRODUCTION:

Ultrasonic is a subject of broad research and as its usefulness in the fields of engineering, pharmaceuticals, biology, geography, biochemistry, geology and polymer industry is found very interesting^1,2. Ultrasonic has also been applied to process monitoring and materials characterization³. Ultrasonic sound velocity (U) together with density (ρ) and viscosity (η) provide a wealth of information about bulk properties and intermolecular forces^4,5, which found applications in several industries and technological processes. The ultrasonic sound velocity is useful in various field of science^6,7,8,9,10.

 

The choice of 1,2,4-triazole is due to its multi-applicability in the field of medicinal chemistry. 1,2,4-Triazole represents a group of heterocyclic compounds with a diverse of biological and pharmaceutical applications. 1,2,4-Triazole derivatives are known to exhibit antimicrobial¹¹, antitubercular¹², anticancer¹³, anti-inflammatory¹⁴ and anticonvulsant activities¹⁵.

 

The present paper describes effect of temperature and solvent on the molecular interactions of 5-(3-methoxyphenyl)-1-phenyl-2-((m-tolylamino)methyl)-1H-1,2,4-triazole-3(2H)-thione (MM4_a) in 1,4-Dioxane at three different temperature (303, 308 and 313) K and atmospheric pressure.

 

EXPERIMENTAL:

MATERIALS AND METHODS:

The 5-(3-methoxyphenyl)-1-phenyl-2-((m-tolylamino)methyl)-1H-1,2,4-triazole-3(2H)-thione(MM4_a) used in this study was synthesized in our laboratory. The molecular weight of compound MM4_a is 402.15 gmole^-1and possible the structure of the synthesized compound MM4_a is shown in Fig. 1.

 

Fig. 1: Structure of 5-(3-methoxyphenyl)-1-phenyl-2-((m-tolylamino)methyl)-1H-1,2,4-triazole-3(2H)-thione (MM4_a)

 

The solvent: 1,4-Dioxane used in present study was of AR grade and purified according to literature method¹⁶.The estimated purity of solvent was more than 99.4 % and was confirmed by GC technique. The 1,2,4-triazole derivative,5-(3-methoxyphenyl)-1-phenyl-2-((m-tolylamino)methyl)-1H-1,2,4-triazole-3(2H)-thione (MM4_a) was synthesized according to standard protocols^17,18.

 

Measurements of density, viscosity and ultrasonic sound velocity:

All the samples were prepared freshly and retained at the desired temperature for 24 hrs, to ensure their dissolvability at the temperature. Samples were kept in bottles with PTFE septum under vacuum until further utilize.

Ultrasonic sound velocity of compound MM4_a (0.01-0.10 mole L^-1) in 1,4-Dioxane were measured at three different temperature(303, 308 and 313) Kby using F-05 multi-frequency ultrasonic interferometer (2 MHz) (Mittal Enterprise, New Delhi). Single Capillary Pycnometer made of borosil glass having knob limit of 10 mL was used to determine density. Ubbelohde viscometer with 25 mL capacity was utilized for the viscosity measurement. Ubbelohde viscometer was calibrated with fresh conductivity water immersed in a water bath that was maintained at the experimental temperature. The flow time of water (t_w) and the flow time of solution, (t_s) were measured with a digital stopwatch with an accuracy of ±0.01 s (Model: RACER HS-10W). The uncertainty of temperature is ±0.1K and that of concentration measured is ±0.001mol×dm^-3.

 

RESULT AND DISCUSSION:

Density, viscosity and ultrasonic sound velocity study:

The data of the density (ρ), viscosity (η) and ultrasonic sound velocity (U) for pure solvent 1,4-Dioxane at the studied temperatures were compared with the literature values and are summarized in table 1. The ρ, η and U of pure solvent and solution of 5-(3-methoxyphenyl)-1-phenyl-2-((m-tolylamino)methyl)-1H-1,2,4-triazole-3(2H)-thione (MM4_a) in 1,4-Dioxane were determined at (303, 308 and 313) K and are reported in table 2.

 

 

Table 1: Comparison of measured density (ρ), viscosity (η) and ultrasonic sound velocity (U) data for pure 1,4-Dioxane with literature values at (303, 308 and 313) K.

 

Fig. 2: The plots of (a) density, (b) viscosity, and (c) sound velocity against concentration (C) for MM4_a in 1,4-Dioxane at 303K (■), 308K (▲) and 313K (´).

 

 

It is clear from Fig. 2 that ρ, η and U increased with concentration (C) and decreased with temperature (T). The concentration and temperature dependence of these data were tested by least square analysis.

 

Theoretical equations of acoustical parameters:

From the experimental data of density (ρ), viscosity (η) and ultrasonic sound velocity (U) various acoustical parameters like Isentropic compressibility (κ_s), Rao’s molar sound function (R_m), Van der Waals constant (b), Internal pressure (p), Solvation number (S_n), Free volume (V_f), Intermolecular free path length (L_f), Viscous relaxation time (τ)were evaluated using standard equations^19-23.

 

Table 2:    The density (ρ), viscosity (η) and ultrasonic sound velocity (U) of compound MM4_a in 1,4-Dioxane at (303, 308 and 313) K.

 

Table 3: The least square equations and regression coefficients of compound MM4a in 1,4 dioxane at (303, 308 and 313) K.

Parameter	Least square equation and regression coefficient, R2
	303 K	308 K	313 K
ρ, kg m-3	y = 18.082x + 1045.8 R² = 0.9945	y = 16.027x + 1031.4 R² = 0.9922	y = 16.822x + 1021.7 R² = 0.9931
η, m Pa/s	y = 0.065x + 1.0596 R² = 0.9852	y = 0.0615x + 0.87 R² = 0.9932	y = 0.0562x + 0.7382 R² = 0.9948
U, m s-1	y = 61.37x + 1375.5 R² = 0.999	y = 64.11x + 1352.1 R² = 0.9922	y = 69.151x + 1278.8 R² = 0.9944
Z, 106 kg m-2 s-1	y = 0.0953x + 1.576 R² = 0.9986	y = 0.0943x + 1.5298 R² = 0.9922	y = 0.0992x + 1.4344 R² = 0.9948
ks, 10-10 Pa-1	y = -0.4807x + 4.613 R² = 0.9988	y = -0.5228x + 4.8346 R² = 0.9919	y = -0.6652x + 5.4518 R² = 0.9945
Lf, 10-11 m	y = -0.235x + 4.4969 R² = 0.9988	y = -0.2496x + 4.6037 R² = 0.992	y = -0.2992x + 4.8887 R² = 0.9946
Rm, 104 m10/3 s-1/3 mol-1	y = 10.66x + 8.5506 R² = 1	y = 10.897x + 8.6095 R² = 1	y = 10.894x + 8.5242 R² = 1
b, 10-5 m3	y = 9.1596x + 7.2486 R² = 1	y = 9.4036x + 7.3314 R² = 1	y = 9.5422x + 7.3715 R² = 1
π, 108 Pa	y = -6.7357x + 5.3698 R² = 0.999	y = -6.266x + 4.9464 R² = 0.999	y = -6.0424x + 4.7338 R² = 0.999
Vf, 10-7 m3	y = 2.6298x + 1.3801 R² = 0.9999	y = 3.4706x + 1.8081 R² = 0.9999	y = 4.1248x + 2.1274 R² = 1
Sn	y = -147513x4 + 35670x3 - 2950x2 + 113.29x - 0.8454 R² = 0.9935	y = -69414x4 + 17080x3 - 1456.5x2 + 69.673x - 0.5572 R² = 0.9995	y = 106556x4 - 17806x3 + 732.43x2 + 18.663x - 0.2166 R² = 0.993
τ * 1013, s	y = -0.2838x + 6.5175 R² = 0.9912	y = -0.2147x + 5.608 R² = 0.9842	y = -0.2515x + 5.3662 R² = 0.9943

 

The thermodynamic activation parameters of the decomposition process of mass loss of molecule such as entropy of activation (DS^#), pre-exponential factor (A), enthalpy of activation (DH^#) and Gibbs free energy of the decomposition (DG^#) were also calculated[24].

 

Least square means that the overall solution minimizes the sum of the squares of the errors made in solving every single equation. The degree of linearity was judged based on the correlation coefficient. A good to excellent correlation between a given parameters and concentration was observed in the studied solvent system at three temperatures. The observed correlation between ρ and C, η and C, and U and C is g = 0.9945-0.9931, 0.9852-0.9948 and 0.999-0.9944 respectively. The obtained g values supported a good to excellent linear dependence of ρ, η and U with C and T. The increase ρ, η and U with C suggest that increase of cohesive forces due to powerful molecular interactions, ultrasonic sound velocity (U) depends on intermolecular free path length (L_f) inversely. The isentropic compressibility (k_s) and intermolecular free path length (L_f) are observed to decrease with C and increase with T suggests the presence of solvent-solute interactions. The linear changes in Rao’s molar sound function(R_m) and Van der Waals constant(b) (correlation coefficient g = 1), suggest that the absence of any complex or aggregate formation takes place in the1,4-Dioxanesolvent system. The internal pressure (π) is the resultant of forces of attraction and repulsion between the molecules in a solution. Free volume (V_f) increased with C and T for solutions of MM4_a in 1,4-Dioxane. The increase in free volume causes internal pressure to decrease or vice versa. The degree of interaction was also measured in terms of solvation number (S_n). It is clear from our results that S_n values are positive which shows the structure forming tendency in the1,4-Dioxane system. The value of least square equation is summarized in table 3.

 

The Gibbs free energy (DG*), enthalpy of activation (DH*) and entropy of activation (DS*) were also measured in 1,4-Dioxane at temperatures (303, 308 and 313) K. and at atmospheric pressure. The results were extrapolated to infinite dilution, which is depicted in fig. 3. A variation in DG* with C and T for compounds MM4_a is summarized in table 4. The value of DG* for compound MM4_a was positive, which suggest astrong interaction between the molecules of solutes and solvent. The linear variation of DG* with C also indicates that the absorption was due to rearrangement of molecules and was independent of concentration.The positive values of DH*suggest that the solute–solvent interaction is endothermic in nature. The negative values of DS* for the solute–solvent interaction process indicate it'snot aspontaneous reaction.

 

Thermal study:

Thermal analysis (TGA and DSC) was carried out using Perkin Elmer TGA and DSC (model No. Pyris-1) instrument under N₂ atmosphere at heating rate of 10°C min^-1

 

The thermal behavior of the synthesized compound was monitored using TGA method. The respective thermogram of MM4_a is shown in fig. 4. It is evident from fig. 5, that MM4_a is thermally stable up to about 100 °C and followed a single step degradation involving about 78.93% mass loss over the temperature range from 100-500 °C leaving 21.57% residue above 500 °C. The maximum mass loss was observed at about 500 °C. The characteristic temperature for the assessment of the relative thermal stability of MM4_a was described here. Initial decomposition temperature (T_o) of compound MM4_a was observed at 100 °C, 10% mass loss (T₁₀) of MM4_a was observed at 265 °C, maximum mass loss (T_max) of MM4_a was observed at 500 °C and final decomposition temperature (T_f) of MM4_a was found at 500 °C. The total mass loss of 98.97% for MM4_a was obtained at the end of the reaction^25,26,27.

 

Table 4: Thermodynamics datawith concentration for MM4_a in the 1,4-Dioxane solvent system at (303, 308 and 313) K and at atmospheric pressure.

 

 

Fig. 3: The plots of Gibbs free energy of activation (DG*) against Molality for MM4a in 1,4-Dioxane at 303K (■), 308K (▲) and 313K (´).

Fig. 4: TGA thermogram of MM4a at the heating rate of 10 °C/min in a N2 atmosphere.

 

CONCLUSION:

The point of the present study is to set up the significance of solution study. The thermodynamic and acoustical behavior of 1,2,4-triazole derivative in 1,4-dioxane were evaluated at three different temperatures at atmospheric pressure and associated kinetic parameters were evaluated. Based on experimental findings, it is concluded that density, viscosity sound velocity increased with concentration and decreased with temperature in the system. Powerful molecular interactions resulted in the structure forming as judged on the basis of positive values of solvation number. Thus, electropositive (–CH₃ and phenyl rings) groups have played an important role in molecular interactions.

 

ACKNOWLEDGEMENT:

The authors are thankful to DST, Govt. of India for providing financial support under FIST-program and also grateful to UGC Govt. of India for recognizing the department under UGC-NON-SAP program. One of the co-authors (Anand A. Jogel) is thankful to University Grants Commission, New Delhi for providing RGNF Scholarship to carry out his Ph.D. program.

 

CONFLICT OF INTEREST:

The authors declare no conflict of interest.

 

REFERENCES:

1.       S. Das and U. Das. Acoustic Parameters of Glycine, α-Alanine and β-Alanine in Aqueous and Aqueous D-Glucose Solutions At 298.15 K. Asian J. Research Chem.2012;5(1):53-56.

2.       Nain, R. Pal and R. Sharma. Physicochemical study of solute–solute and solute–solvent interactions of l-histidine in water + sucrose solutions at different temperatures. J. Mol. Liq.2012; 165:154.

3.       T.J. Mason. Sonochemistry. Royal Society of Chemistry, United Kingdom. 1990.

4.       V.F. Nozdrev. Application of Ultrasonic in Molecular Physics. Gordon and Breach, New York. 1963.

5.       D.C. Pierce. Acoustics. Mc-Grew Hill, New York. 1981.

6.       R. Kumar et al. Ultrasonic and spectroscopic studies on hydrogen bonded complexes of aromatic amine and aryl ketones in n-hexane at 303.15 K.J. Mol. Liq.2011; 163(2): 57.

7.       C. Zhang, F. Zhao and Y. Wang. Thermodynamics of the solubility of sulfamethazine in methanol, ethanol, 1-propanol, acetone, and chloroform from 293.15 to 333.15 K.J. Mol. Liq.2011; 159(2): 170.

8.       S. Baluja and S. Oza. Ultrasonic studies of some derivatives of sulphonamide in dimethylformamide. Fluid Phase Equil. 2002; 200: 11.

9.       S. Baluja and A. Shah. Acoustical studies of some derivatives of 4-amino antipyrene in 1,4-dioxane and dimethylformamide at 318.15 K. Fluid Phase Equil. 2004; 215: 55.

10.     D.R. Godhani and P.H. Parsania. Studies on acoustical properties of poly (4,4'-diphenylphthalidediphenyl-4,4'-disulfonate) at 30⁰C.J. Ind. Chem. Soc. 2002; 79:620.

11.     R. Mishra et al. Synthesis and in vitro antimicrobial activity of some triazole derivatives. J. Chil. Chem. Soc. 2010; 55(3): 359.

12.     A. Foroumadi, Z. Kiani and F. Soltani. Synthesis and in vitro antimycobacterial activity of alkyl alpha-[5-(5-nitro-2-thienyl)-1,3,4-thiadiazole-2-ylthio]acetates-II.Farmaco.2003; 58:1073.

13.     M.S. Karthikeyan et al. Synthesis and biological activity of Schiff and Mannich bases bearing 2,4-dichloro-5-fluorophenyl moiety. Bio org.  Med. Chem. 2006; 14:7482.

14.     M.F. El-Shehry et al. Synthesis of 3-((2,4-dichlorophenoxy)methyl)-1,2,4-triazolo(thiadiazoles and thiadiazines) as anti-inflammatory and molluscicidal agents. Eur. J. Med. Chem.2010; 45:1906.

15.     J. Chen, X.Y. Sun, K.Y. Chai. Synthesis and anticonvulsant evaluation of 4- (4-alkoxylphenyl)-3-ethyl-4H-1,2,4-triazoles as open-chain analogues of 7-alkoxyl-4,5-dihydro[1,2,4]triazolo[4,3-a] quinolines. Bio org.  Med. Chem. 2007; 15: 6775.

16.     J.A. Riddick, W.B. Bunger and T. Sakano, Organic Solvents-Physical Properties and Methods of Purification. Techniques of Chemistry. New York. 1986.

17.     D.R. Godhani et al. Synthesis, antibacterial and antifungal activity of some new [1,2,4]-triazole-3-thiones.Ind. J. Het. Chem. 2011; 20: 411.

18.     D.R. Godhani et al.Synthesis and antimicrobial elucidation of [1,2,4]-triazole-3-thione derivatives. J. Ind. Chem. Soc.2012; 89: 971.

19.     S. Bagchi et al. Ultrasonic and viscometric investigation of ISRO polyol in various solvents and its compatibility with polypropylene glycol. Eur. Polym. J. 1986; 22(10): 851.

20.     P. Vigoureux. Ultrasonic.Chapmann and Hall, London. 1952.

21.     C.V. Suryanarayana. Internal pressure and free volume – The key parameters in characterizing liquids and electrolytic solutions. Acoust. Soc. Ind. 1979; 7:131.

22.     C.V. Surayanarayana and J. Kuppusami. Free volume and internal pressure of liquids from ultrasonic velocity. J. Acous. Soc. Ind. 1976; 4:75.

23.     B. Jacobson, A. Anderson. A proton magnetic resonance study of the hydration of deoxyribonucleic acid. Nature. 1954; 173:772.

24.     E.S. Freeman and B. Carroll. The application of thermoanalytical techniques to reaction kinetics. J. Phys. Chem.1958; 62:394.

25.     A.A. Soliman. Thermogravimetric and Spectroscopic. Kluwer Academic Publishers, Giza Egypt. 2001.

26.     D.A. Anderson and E.S. Freeman. Kinetics of the thermal degradation of polystyrene and polyethylene.J. Polym. Sci.1961; 54:253.

27.     G. Chatawal, S. Anand. Instrumental methods of chemical analysis. 2^nd edition. Himalaya Publishing House,Mumbai. 1984.

28.     J.G. Baragi et al. Density, viscosity, refractive index, and speed of sound for binary mixtures o 1,4-dioxane with different organic liquids at 298.15, 303.15, and 308.15 K.J. Chem. Eng. Data.2005; 50: 917.

29.     M.V. Rathnam et al. Studies on excess volume, viscosity, and speed of sound of binary mixtures of methyl benzoate in ethers at T= 303.15, 308.15, and 313.15 K.Journal of Thermodynamics. 2013; 2013:1.

30.     S. Baluja, N. Vekariya. , Acoustical studies of some derivatives of 4-amino benzoic acid in 1, 4-dioxane and dimethyl formamide at 308.15 K. Iran. J. Chem. Eng.2008; 27(1): 129.

31.     F. Corradini and G.C. Franchini. Densities and Excess Molar Volumes of 2-Methoxy ethanol/ Water Binary mixture.J. Chem. 1992; 45: 1109.

32.     G. Oskoei and N. Safaei. Densities and Viscosities for Binary and Ternary Mixtures of 1, 4-Dioxane + 1-Hexanol + N,N-Dimethylaniline from T = (283.15 to 343.15) K.J. Chem. Eng. Data.2008;53: 343.

33.     S.Villares and N. Martı. Densities and speeds of sound for binary mixtures of (1,3-dioxolane or 1,4-dioxane) with (2-methyl-1-propanol or 2-methyl-2-propanol) at the temperatures 298.15 and 313.15 K.J. Chem. Therm.2004; 36: 1027.

34.     T. Takigawa and K. Tamura. Thermodynamic properties of (1, 3-dioxane, or 1, 4-dioxane+ a non-polar liquid) at T= 298.15 K; speed of sound, excess isentropic and isothermal compressibility's and excess isochoric heat capacity. J. Chem. Therm.2000; 32:1045.

35.     K.A. Kumar and S. Ch, S. Raju. Densities, Ultrasonic velocities and Excess properties of Binary mixture of 1, 4-Dioxane + 1-Butanol at Temperatures between (298.15 and 318.15) K.J. Chem. Bio. Phy. Sci.2013; 3:2914.

 

 

 

Received on 17.10.2017         Modified on 25.11.2017

Accepted on 07.12.2017         © AJRC All right reserved