Synthesis, Characterization and Antifungal Activity of Metal (II) Complexes of Azodyes with 4-[(4-Aminophenyl) Diazenyl]-3-Methyl-1-Phenyl-1H Pyrazol-5-Ol

Synthesis, Characterization and Antifungal Activity of Metal (II) Complexes of Azodyes with 4-[(4-Aminophenyl) Diazenyl]-3-Methyl-1-Phenyl-1H Pyrazol-5-Ol

Dr.Vittala Rao K S(1) , Dr.Vasanth Patil S B(2)

(1)Department of Chemistry, (2)Department of Geology Sahyadri Science College, Shivamogga, India

Abstract – A series of metal complexes of Cu(II), Co(II), Mn(II),Ni(II) and Zn(II) with Azodyes of novel heterocyclic pyrazole derived from 4-[(4-aminophenyl) diazenyl]-3-methyl-1- phenyl-1H pyrazol-5-ol have been synthesized and characterized on the basis of elemental analysis, mass, IR, H1NMR and magnetic study and thermo gravimetric analysis. These compounds were screened for their anti-microbial activity, many of them found to be potent as anti- microbial.

Keywords – Transitional metal complexes; Azodyes; pyrazole; elemental analysis; H1NMR.

1. INTRODUCTION

   The coordination chemistry of nitrogen-oxygen donor ligands are interesting area of research (1). Metal complexes of pyrazole played a major role in development of coordination chemistry (2). Ligands bearing nitrogen, oxygen and sulphur as donor atoms possess significant antifungal, antibacterial and anticancer activities and also some complexes show catalytic property (3). Some Ligands complexes show increased in their activity due to complexesation (4). Azo dyes frequently chelates to metal ions through a combination of hydroxyl group (5) and azo group. These interactions have greatly inspired the chemists to study the azodyes as analytical reagents (6). Due to the presence of one or more azo (N=N-) groups, these dyes posses several distinctive properties, including aggregation and optical data storage, which define them as a distinct class of dyestuffs (7). The widespread application of azo compounds and their metal chelates as dyes, acid- base indicators, and histological stains has attracted the interest of many investigators (8). Azo compounds can also exhibit strong pharmacological activities

   (9). The interesting fact that azo derivatives are attributed to complexing capacity, model for biological systems and chromogenic reagents (10).

   Traditionally, azodyes are most essential class of commercial dyes. They possess very high colour, hence used as dyes and pigments (11). In addition they have been studied broadly because of their outstanding thermal and optical properties (12), such as tonor, (13) ink-jet printing (14) and oil soluble light fast dyes (15). The complexes opted importance

   due too their interesting electronic and geometrical features in connection with their application for molecular memory storage, nonlinear optical elements and printing system (16). Dyes used before nineteenth century were either of vegetable (weld, madder, indigo) or animal origin (cochineal, shellfish) and belonged to various chemical types, such as flavonoids (yellow), Anthraquinones (red) and indigos (blue and violet)

   (17). Synthetic dyes are extensively used in industry and a vast amount of the dye produced enter the environment as waste material (18) azo dyes are widely used in textile industry and are the largest and most versatile group of synthetic organic dyes, with a tremendous number of industrial applications (19).

2. EXPERIMENTAL

   All chemicals, solvents used were analytical grade and all metal salts used were metal (II) acetate. The elemental analysis was carried out at sophisticated test instrumentation center (STIC) Cochin. Infrared spectra of azodyes and complexes were recorded in the region of 4000-400cm-1 on a FT-IR Nicolet Impact 410 0n KBr pellets. The 1H NMR were recorded in CDCl3 on Bruker AVIII 400 MHz with tetramethylsilane as internal standard. The mass spectrums were recorded with a LC-MSD-XCT plus mass spectrometer. UV-Visible spectra were recorded in methanol and chloroform with UV-Visible spectrometer 119 in wave length range of 230-500nm. Thermal analysis was carried out in SHIMADZU TA-60WS Thermal analyzer in air at a heating rate of 50C min-1.

   Synthesis of 3-methyl-1-phenyl pyrazole

   Ethyl acetoacetate (0.01mol) was mixed with phenylhydrazine (0.01mol) in 250ml round bottomed flask refluxed, for 2hours on water bath; the compound which was not true hydrazone was first formed. This under goes cyclisation with loss of ethyl alcohol, upon further heating forms heavy reddish syrup, which was allowed to cool, add ether and stirred vigorously. The insoluble part gets solidified, filtered and recrystalised with equal volume of ethyl alcohol and water.

   (MeOH), 238 (0.728) 423 (0.193). IR absorption bands (cm-1) 507m, 689w, 826w, 1156s, 1492s, 1594s, 2922m, 3447b.

   Synthesis of Manganese (II) complex derived from 4-[4-

   3 NH

   Synthesis of Amino- benzene diazonium chloride:-

   P-phenalenediamine (0.1mole) was dissolved in hydrochloric acid (0.2mole per 25ml of distilled water).The hydrochloride derivative of P-phenalenediamine was diazotized below 50C with a was coupled with acidic solution of 3-methyl- 1-phenyl pyrazole (0.1mole acetic acid), stirred for one hour at ice bath temperature, then sodium acetate was added (0.1mole 20ml) as a buffer to maintain PH between 4-5.5and the mixture left overnight. The crude dyes were collected by filtration and recrystalised with mixture ethyl alcohol and water. Yield 75%.

   M. P; 2930C. Anal. Calcd. for C16H15N5O (%) C, 65.00; H,

   5.11; N, 23.89. Found. C, 64.79 ; H, 5.41; N, 23.78. UV

   Visible (CHCl3), 239 (2.489), 232 (2.328) 431 (0.161) and in

   (MeOH) 239 (1.740), 253 (1.701) 453 (0.915). IR absorption bands (cm-1) 850w, 1155s, 1496s, 1552s, 2923m, 3450 b. 1H NMR (400 MHz, CDCl3) d (ppm) 2-3 (3H. M, CH3) 6.7-8.2

   (9H. M 9CH) 3.8-4 (2H S NH) 6.8-6.9 (H S OH) 13.8 (H S OH).

   Synthesis of complexes:-

   Synthesis of copper (II) complex derived from 4-[4- aminophenyl) diazenyl]-3-methyl-1-phenyl-1H pyrazol-5-ol

   5mmol of dye was dissolved in 20ml of 1:1 mixture of methanol and chloroform in 250 ml round bottomed flask carrying reflux condenser. To this add 2mmol of copper (II) acetate, and warmed on water bath maintained at 60- 650C for one hour, the mixture was kept overnight. The cake was ground and washed with ethyl alcohol, complex gets precipitated was filtered and dried. The formation of ligand and transition metal complexes are characterized by C.H.N, I.R, NMR, mass spectra, UV-visible studies. Thermal stability of dyes was examined by TGA-DTA studies and electrochemical nature of dyes was studied by cyclic voltmetry studies. Yield 82%. Anal. Calcd. for C32H28N1002Cu (%) C,59.3; H, 4.35; N, 21.61. Found C, 59.45; H, 4.22 N, 21.09. UV-Visible (CHCl3), 239 (2.489) and

   (MeOH), 240 (1.314). IR,absorption bands (cm-1) 507m, 689w, 845. 4-[4-aminophenyl) diazenyl]-3-methyl-1-phenyl- 1H pyrazol-ol.

   aminophenyl) diazenyl]-3-methyl-1-phenyl-1H pyrazol-5-

   ol

   Yield 73%. Anal. Calcd. for C32H28N1002Mn (%) C, 60.09; H, 4.41; N, 21.90. Found C, 59.86; H, 4.33 N, 21.78.

   UV-Visible (CHCl3), 234 (2.500) 431 (0.329) and (MeOH),

   251 (0.486) 446 (0.358). IR absorption bands (cm-1) 466m, 689w, 825w, 1159s, 1498s, 1594s, 2923m, 3447 b.

   Synthesis of Zinc (II) complex derived from 4-[4- aminophenyl) diazenyl]-3-methyl-1-phenyl-1H pyrazol-5- ol

   Yield 70%. Anal. Calcd. for C32H28N1002Zn. (%) C,

   59.13; H, 4.34; N, 21.55. Found C, 59.04; H, 4.82 N, 21.24.

   UV-Visible (CHCl3), 239 (2.490) 441 (0.137) and (MeOH),

   244 (0.351) 446 (0.183). IR absorptin bands (cm-1) 467m, 689w, 834w, 1155s, 1495s, 1594s, 2923m, 3447 b. 1H NMR

   (400 MHz, CDCl3) d (ppm) 1-2 (3H. M, CH3 and one due to CDCl3) 6.8-7.5 (9H. M 9CH) 2.2 (2H s NH)

   Synthesis of Nickel (II) complex derived from 4-[4- aminophenyl) diazenyl]-3-methyl-1-phenyl-1H pyrazol-5- ol

   Yield 74%. Anal. Calcd. for C32H28N1002Ni. (%) C,

   59.74; H, 4.39; N, 21.77. Found C, 59.57; H, 4.23 N, 21.42.

   UV-Visible (CHCl3), 239 (2.407) 422 (0.068) and (MeOH),

   251 (0.704) 417 (0.264). IR absorption bands (cm-1) 502s, 688w, 835m, 1169s, 1492s, 1593s, 2922m, 3449 b.

   All the other metal (II) complexes were prepared by the above procedure using the respective azodyes and metal salts.

3. RESULTS AND DISCUSSION

   Electronic Spectra of azodyes complexes

   The electronic spectrum of Cu (II) complex generally show a broad band, suggesting that merging of electronic transitions 2B1g2B2g; 2B1g 2A1g and 2B1g2E at 240nm. A square planar geometry has been proposed (20). The absorption spectral data of Co (II) complex show (232,238, 239,422 and 423) several bands assigned to 4T1g (F)4T2g (F), and 4T1g (F)4T1g (P) transitions indicating -* and charge transfer, which propose octahedral structure for the

   complex (21).

   The Mn (II) complex absorb at (234,251, 431 and 446), these bands are attributed to various spin forbidden

   O N quartet states, which are consistent with the octahedral geometry. The absorption spectra of Zn (II) complexes show

   bands 239, 244, 441 and 446. These absorption bands are due to -* and n- * charge transfer transitions. The absorption

   Synthesis of cobalt (II) complex derived from 4-[4- aminophenyl) diazenyl]-3-methyl-1-phenyl-1H pyrazol-5- ol

   Yield 78%. Anal. Calcd. for C32H28N1002Co (%) C,

   59.72; H, 4.39; N, 21.77. Found C, 59.32; H, 4.18 N, 21.10.

   UV-Visible (CHCl3), 239 (2.492) 232 (2.331) 422 (0.115) and

   spectrum of Ni (II) complex shows 239, 251, 417 and 422. These bands are assigned to -* and n- * charge transfer transitions (ML) and 1A1 (G) 1B1 (G) transition, the absorption intensity of these bands indicate a square planar geometry for the complex (22).

   1H NMR Spectrum:-

   The 1H NMR are recorded on Bruker VIII (400 MHz, CDCl3) at SAIF, Cochin, Kerala. The 1H NMR spectra show multiplets between 7-8.4ppm assigned to aromatic ligand protons. The peak at 1.2-1.4 ppm was due to methyl protons and the peak 14.8 corresponds to OH proton. Similarly the peak at 7-8.5 ppm assigned to aromatic protons of complexes, the peak at 1.8ppm was due to methyl protons and the peak at

   14.8 ppm attributed to co-coordinated water molecule.

   FT-IR Spectrum:-

   The infrared spectral data reveal and broad bands in the range of 3250-3500cm-1 attributed to the existence of amino group, coordinated and crystallized water molecules

   (23). The absorption band at3100- 3050 cm-1 are assigned to aromatic stretching 2950-2900 cm-1 are due to methyl group, the band 1500-1560 cm-1 was assigned to C=N, the absorption band at 1438-1497 cm-1 are attributed to N=N- bond involved in chelation (24). The band at 650-880 cm-1 was assigned to coordinated water to metal ion (25). The new bands arise at 690-630 cm-1 and 501-470 cm-1are due to the presence of M-O and M-N bonds (26).

   Fig. 1. IR spectrum of ligand and complexes of 4-[4-aminophenyl) diazenyl]- 3-methyl-1-phenyl-1H pyrazol-5-ol

   Fig. 2. 1H NMR Spectrum of 4-[4-aminophenyl) diazenyl]-3-methyl-1- phenyl-1H pyrazol-5-ol

   Fig. 3. 1H NMR Spectrum of complex 4-[4-aminophenyl) diazenyl]-3- methyl-1-phenyl-1H pyrazol-5-ol

   Powder XRD Studies

   X-ray powder diffraction patterns in the 50<2<900 of the compounds were carried in order to obtain an idea about the lattice dynamics of the compound. By comparison of the obtained X-ray powder diffraction patterns shown in figure the

   X-ray powder diffraction pattern throws light only on the fact that each solid represents a definite structure which was not contaminated with the starting materials. The identification of the complexes was done by known method. Such fact suggests that the prepared compounds are amorphous (27).

   Fig. 4. The powder XRD pattern of metal complexes

   Mass spectra of ligand

   The purity of the ligands A1 and B1 was checked from mass spectra.The spectra clearly showed base peaks (m/e) 293 as molecular weight. The MALDI was carried out to few samples, which indicate the formations of metal complexes are in the ratio of 1:2.

   Magnetic property

   Magnetic susceptibility measurements of all the complexes were carried out at room temperature by Gouy method, Hg [Co (NCS)4] used for calibration. Molar Susceptibilities were corrected for diamagnetism of component atoms using Pascals constant.

   The magnetic moment for the Cu (II) ion, d9 has electronic configuration t2g6 eg3 found closer to spinning only. The magnetic moments of copper complexes are in the range of 2.19-2.31. These values assigned to square planar geometry. The Co (II) complex show 4T2g (F) 4T1g(F), 4A2g(F) 4T1g(F) and 4T1g(F) 4T1g(F) transitions, they are assigned with high spin octahedral geometry. Co (II) complex exhibits a magnetic moment of 4.2 B.M. This higher value was attributed to the orbital magnetic moment (28).

   The Mn (II) has d5 configuration with magnetic moment 5.8 B.M. These Magnetic moment correlates very well with the mononuclear complexes, and complexes are assigned with a high spin octahedral geometry (29). The Zn

   (II) complexes has d10 electrons and electronic configuration t2g6 eg4, The magnetic moment of Zn (II) complexes are found to be diamagnetic in nature, and they had been suggested square planar geometry. The Ni (II) complex has d8 electrons and electronic configuration t2g6 eg2 and has square planar geometry and diamagnetic property (30).

   Anti-fungal activity

   An antifungal agent was a drug that selectivity eliminates fungal pathogens from a host with minimal toxicity to the host. They are used to treat common conditions, such as

   athletes foot, ringworm, dandruff and virginities as well as serious infections that have spread throughout the body. Antifungal medication was often used in individuals with poorly functioning immune systems. As observed in people with aids, and in people who are taking drugs that suppress immune function.

   The development of antifungal agents has lagged that of antibacterial agents. This was a predictable consequence of the cellular structure of the organisms involved. Bacteria are prokaryotic and hence offer numerous structural and metabolic targets that differ from those of the human host. In contrast funguses are eukaryotes, and consequently most agents toxic to the host. Further more, because fungi generally grow slowly and often in multicellular forms, they are more difficult to quantify than bacteria. This difficulty complicates thee experiments designed to evaluate the invitro or invivo properties of antifungal agent. Despite these limitations, numerous advances have been made in developing new antifungal agents and in understanding the existing ones.

   Metal complexes have been proved to be more toxic to fungi, compared to the organic compound (32). Dithiocarbamate, morpholinedithiocarbamates and diphenyl dithiocarbamate complexes of Cu (II), Co (II), Mn (II), Zn (II) and Ni (II)have been found to be active against certain fungi, namely Helminthosporiumgoffybii and Alternaria solanae. Copper (II) sulphate and copper (II) oxychlorides are very effective against species of Apergillus, Penicilium, Fusarium and Gliocledium (33). Further the chelation in these compounds was responsible for antifungal and antibacterial activity. (34) Transition metal complexes of azo dyes such as methyl orange have pronounced antifungal and antibacterial activity (35). Copper complexes are found to be more effective against Aspergillus niger. These effects were attributed to slow release of Cu2+ into the culture medium, there by causing inhibition of fungus (36).

   Thermal properties and Kinetic parameters.

   The thermodynamic activation parameters of decomposition processes of complexes, namely activation energy (Ea), enthalpy ( H), entropy ( S) and Gibbs free energy ( G) Change in decomposition temperature were calculated. The entropy of activation had negative values in all the complexes, which indicate that the decomposition reaction proceed with a lower rate than normal ones. The structure of complexes were confirmed by elemental analysis, IR, NMR, UV-Visible, mass, magnetic and thermal studies. The IR spectra concludes that the azodye behaves as neutral bidentate ligand, coordinated to the metal ions through N and O. (-N=N- and OH) On the basis of the above observations, octahedral and square geometries are suggested for investigated complexes (31).

   TABLE 1: Kinetic parameters of complexes.

4. CONCLUSION

The transition metal(II) complexes possess NLO and high thermal stability hence used in memory storage devices.The ligand and complexes show potent anti-fungal activity. We conclude the formation of complexes is in the ratio of 1:2 from elemental and spectral analysis.

Acknowledgment

We are thankful to the Principal, Sahyadri Science College Shivamogga, a constituent college of Kuvempu University for providing facilities.

REFERENCES

1. M.Neelamma, P. Venkateswar Rao and G.H. Anuradha. E-Journal of chemistry.2011, 8 (1), 29-36.
2. Murulidhar Reddy P, Ashok M, Usha Rani P and Ravindaran V, Int J Chem Sci., 2007, 5 (2), 489-495.
3. Karvembu R, Hemalatha S, Prabhakaran R and Natarajan K, Inorg chem. Commun., 2003, 6, 486-490.
4. Karidi K, Garoufis A, Tsipis A, Hadjiliads N, Dulk H and J Reedijk, J Chem Soc Dalton Trans, 2005, 1176.
5. Bishop E (ed) Indicators. Pergamon Press, Oxford. 1972.
6. Chen X, Zhang J, Zhang H, Jiang Z, Shi G, Li Y, Song Y 2008, Dyes Pigments 77: 223.
7. Fabian WM, Antonov L, Nedeltcheva D, Kamounah FS, Taylor PJ 1997, J Phys Chem 108: 7603.
8. Jannkaudakis D, Thedoridou E, Pekekourla A 1972, Chem Chron 1:69.
9. Mehmet Tuncel, Hulya Kahyaoglu and Mehmet Cakir, Trans Met Chem,
   

   2008, 11243-008-9087-6

10. S Zeynel, E. Nermin, Y. Ebru, U. Guven, Color Technol. 124 2007, 27.
11. H.M.Shukla, A.I Shah and D.S.Raj Rasayan J .Chem.vol3. no3. 2010, 525-531.
12. K. Maho, T. Shintaro, K. Yutaka, W.Kazuo, N. Toshiyuki and T.Mosahiko, Jpn J. Appl.Phys., 42, 1068, 2003.
13. P. Gregory, D.R. Waring and G.Hallos, The Chemistry and Application of dyes, Plenum Press, London, PP 18-20, 1990.
14. H.E. Katz, K.D.singer, J.E. Sohn, C.W. Dirk, L.A.King and H.M.Gordon, J. Am, Chem.Soc., 109 (21), 6561, 1987.
15. T. Chino, M. Yamada, JP 2001220519, 2002.
16. S. wang, S.Shen and H.Xu, Dyes pigments, 44, 195, 2000.
17. W.Nowik, Encyclopedia of separation sciences, Academic Press, London, 2000,p 2602.
18. H. Zollinger, Color Chemistry Synthesis Properties and Application of Organic Dyes and Pigments, VCH Publishers, New York, 1987, p.1436.
19. H. Ollgaard, L.Frost, J.Galster, O.C .Hansen, Survey of azo-colorants in Denmark: consumption use health and environmental aspects. Ministry of Environment and Energy, Denmark and the Danish Environamental Protectoion Agency, No. XX 1998, p 147.
20. Satwinder S.M, Jasjest K and Guruvinder S.S,Met Based Drugs,1995. 2(1), 13-17.
21. Sanchez M and Aracona J.R.T, J Chil Chem Soc 2005, 50 (1), 1-5.
22. A.I Vogel, A text book of practical organic chemistry, Third edition,

    Longmans London 1961

23. Bellamy L J, Infrared spectra of Complex Molecules; Chapman and Hall Ltd.: London, 1975
24. Kovacic J E, Spectra Chim Acta, 1987, 23a, 183. (-N=N-)(involved in chelation)
25. Gurudeep R Chatwal, Sham K. Anand. Advanced Inorganic Chemistry. Himalaya Publishing House.
26. A. Halve, A. Goyal, Orint J. Chem 12 (1) 2001. 87
27. Introduction to solid state Physics, Kittel. Tata McGraw-Hill Publications, London.
28. Cotton F.A and Wilkinson G. Advanced Inorganic Chemistry, Wiely Inter Science, New York. 1998.
29. Neelamma M, Venkateswara Rao.P and Jyothi. V, Int J. Pure Appl Chem., 2007, 2 (1), 127-133.
30. David. N, Complexes and First Row Transition Elements; American Elsevier, 1984.
31. AMS. El-Sharief, M.S. Ammar, Y.A. Ammar and M.E.Zak, Ind. J. Chem. 22B, 700-704, 1983.