Research Journal of Chemical Sciences ______________________________________________ ISSN 2231-606X Vol. 3(1), 48-56, January (2013) Res.J.Chem. Sci. International Science Congress Association 48 Synthesis, Characterization and Antimicrobial Studies of Coordination Polymers Shukla Hemang M., Solanki Yogesh K., Shah Ashish R., Shah Purvesh J., Shah Amish I. and Raj Dilipsinh S.1 Chemistry Department, M.B. Patel Science College, Managed by C. E. Society, Anand -388001, Gujrat, INDIA Chemistry Department, Shri A.N. Patel P.G. Institute, Managed by C. E. Society, Anand-388001, Gujrat, INDIAAvailable online at: www.isca.in Received 13th September 2012, revised 15th October 2012, accepted 15th November 2012Abstract Novel bis ligand namely 2,2'-(4,4'-(1,2-phenylenebis(diazene-2,1-diyl))bis(4,1-phenylene))bis (azanediyl) bis(oxomethylene) dibenzoic acid(OPDAL)has been prepared and characterized. The co-ordination polymers based on this bis ligand with transition metal ions like Cu+2,Co+2,Ni+2,Mn+2and Zn+2 were prepared and studied for their metal: ligand (M/L) ratio, IR and reflectance spectroscopies, magnetic properties, number-average molecular weight and by thermogravimetry. All the novel synthesized compounds were screened for their antibacterial and antifungal activities. Keywords: Co-ordination polymer, bis azo ligand, magnetic properties, spectral studies and microbicidal activity. Introduction Traditionally, azo dyes are the most fundamental class of commercial dyes. The azo compounds are well colored and have been used as dyes and pigments. In addition, they have been studied usually because of their excellent thermal and optical properties in purposes such as toner, ink-jet printing3 and oil-soluble lightfast dyes optical recording medium 5-6. In modern times, azo metal chelates have also paying attention due to their interesting electronic and geometrical features in link with their application for molecular memory storage, nonlinear optical elements and printing systems6,7. Recently, the study of co-ordination polymers has been made much progress8,9. These polymers are known for their semiconducting catalytic properties, waste water treatment for metal recovery, in protective coating, as antifouling paints and anti fungal properties10. Such Coordination polymers are mostly derived from bi-chelating ligands in which metal ions and chelating agents are grouped alternatively. The joining segment of these two similar ligands are mainly –N=N-, SO, -CH2 -, -O- 11-15. Co-ordination polymers mostly derived from bichelating ligands in which metal ions and chelating agents arrayed alternatively 16-17. The area in which the co-ordination polymers having azo dye moiety has been reported18. In extension of previous work, the present article comprises the study of co-ordination polymers based on bisazo dye with phthalamic acid segment. Though phthalamic acid also act as good metal chelating agent. In the present article, we report the synthesis, spectral studies and magnetic properties as well as antibacterial and antifungal activities of all the novel synthesized compounds and its metal chelates. Thus paper connecting with the studies of co-ordination polymers based on amic acid functionalized bisazo dye. The synthetic routes are shown in figure-1. Material and Methods Benzene-1, 2-diamine was obtained from S. D. Fine Chemical Ltd. All other chemicals used were of analytical grade. Synthesis of 4,4'-(1,2-phenylenebis(diazene-2,1-diyl)) dianiline (A): A solution of 10.8 g (0.1mole) of Benzene-1,2-diamine in 250 ml 2N HCl was cooled in a round bottom flask, surrounded by ice and stirred with electric motor, when solution was cold, add few pieces of ice and 200 ml 1N nitrite solution was added drop wise from a dropping funnel at below 0C with stirring. After completing the addition of nitrite mixture was stirred for about 10 mins. Then tested to make sure that it gave strong blue coloration with Congo red paper and weak blue test with starch iodide paper, added distilled water in it dilute the solution and kept it into ice-bath. A solution of dil. HCl added into aniline 18.6 gm (0.2 mole) till Congo Red Paper gave blue color, now added above diluted diazonium solution into aniline solution gradually in cold situation, stirred it well and add sodium acetate solution till the neutralization of dye. Now washed the dye with cold water. The products were obtained in the form of dark yellow color, collected that dye by vacuum filtration, then wash with cold water & dry it over night. Yield 78%, M.P.196c (uncorrected). Analysis C18166 (Cal : %C 68.34, % H 5.10, % N 26.56; Found: % C 68.26 , % H 5.02, % N 26.50). Synthesis of 2,2'-(4,4'-(1,2-phenylenebis(diazene-2,1-diyl))bis(4,1-phenylene) )bis(azanediyl) bis(oxo methylene) dibenzoic acid(OPDAL):The solution of 4,4'-(1,2-phenylenebis (diazene-2,1-diyl)) dianiline (0.1 mole) in acetone is cooled to 10°C.To this solution the phthalic anhydride (0.2 mole) was added with stirring. The resulting product was then filtered and air-dried.Yield 79%, M.P. 260C (uncorrected). Analysis: C34246 (Cal : %C 66.66,% H 3.95,% N Research Journal of Chemical Sciences ___________________________________________________________ ISSN 2231-606XVol. 3(1), 48-56, January (2013) Res. J. Chem. Sci. International Science Congress Association 49 13.72;Found: % C 66.36, % H 3.71, % N 13.42). 1H-NMR (400 MHz, DMSO-d (ppm):12.6-11.0(s, 2H,-COOH),9.3-9.15 (, 2H, -CONH, DO exchangeable), 8.0-7.50 (m,20H, aromatic, = 0.9,7.8Hz).13CNMR-131.5(C-1,C-13), 130.1(C-2,C-12),128.6(C-3,C-11), 132.0 (C-4,C-10), 134.0 (C-5,C-9), 123.5(C-6,C-8),124.4 (C-17, C-21, C-24,C-28), 119.3(C-18, C-20,C-25,C-27), 150.9(C-22,C-23),140.1(C-19, C-26), 167.6(C-7,C-16), 173.0 (C-14,C-15),146.7(C-30,C-31),123.3(C-29,C-32),131.2(C-33,C-34).The predicted structure and formation of polymeric ligand is shown in figure-1. Estimation of number of carboxylic (-COOH) groups in ligand OPDAL: The structure of ligand was examined by estimation of number of carboxylic –COOH groups per mole of ligand. The non-aqueous conductometric nitration was employed for –COOH group estimation following the method reported in the literature19-20. The titrant used for this non-aqueous titration was tetra-n-butyl ammonium hydroxide (TBAH) in pyridine. Preparation of Co-Ordination Polymers:All co-ordination polymers were synthesized by using metal acetate in general method described. A warm and clear solution (pH8) of OPDAL (6.12gm, 0.01mole) in aq. NaOH (200 ml) was added to a solution of copper acetate (1.99 gm, 0.01mole) in 50% aq. formic acid (50 ml) with constant stirring. After complete addition of metal salt solution, the pH of reaction mixture was adjusted to about 5 with dilute ammonia solution. The polymer chelate was separated out in the form of suspension, digested on a water bath for on hour and eventually filtered, washed with hot water followed by acetone, dimethyl formamide (DMF) and then dried in air at room temp. The yields of all co-ordination polymers were almost quantitative. Figure-1 Synthetic route for Preparation of Co-Ordination Polymers Research Journal of Chemical Sciences ___________________________________________________________ ISSN 2231-606XVol. 3(1), 48-56, January (2013) Res. J. Chem. Sci. International Science Congress Association 50 Measurements: The metal analysis of co-ordination polymers comprised decomposition of a weighted amount of the polymer followed by EDTA titration following standard procedures21. C, H, N analysis of OPDAL and its coordination polymers were carried out by C, H, N elemental analyzer (Italy). IR spectra of the ligand and of each of the polymer samples were scanned in KBr on a Nicolet 760 D spectrophotometer. The solid diffusion reflectance spectra of all co-ordination polymer samples were recorded on a Backman DU spectrophotometer with a solid reflectance attachment. MgO was employed as the reference compound. The number average molecular weight Mn ) of all the coordination polymers were determined by method reported in earlier communications22. Magnetic Susceptibility measurements of all co-ordinate polymers were carried out at room temperature by the Gouy method, Hg[Co(NCS)] used for calibration. Molar Susceptibilities were corrected for diamagnetism of component atoms using Pascal’s constant. Thermogravimetry of polymer samples were carried out on a “PERKIN ELMER PYRIS 1 TGA in a slow stream of air. The diffuse reflectance spectra of the solid polymeric chelates were recorded on a Beckman DK-2A spectrophotometer with a solid reflectance attachment. MgO was employed as the reference compound. Antibacterial Activities: Antibacterial activity of OPDAL ligand and its coordination polymers were studied against gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) and gram-negative bacteria (E.coli and Salmonella typhi) at a concentration of 50g/ml by agar cup plate method. Methanol system was used as control in this method. The area of inhibition of zone measured in mm. Antifungal Activities: The fungicidal activities of all the compounds were studied at 1000 ppm concentration in vitro. Plant pathogenic organisms used were Penicillium expansum, Nigrospora Sp., Trichothesium Sp. and Rhizopus nigricum. The antifungal activity of ligand and its coordination polymers were measured on each of these plant pathogenic strains on a potato dextrose agar (PDA) medium. Such a PDA medium contained potato 200 gm, dextrose 20 gm, agar 20 gm and water one liter. Five days old cultures were employed. The compounds to be tested were suspended (1000 ppm) in a PDA medium and autoclaved at 120°C for 15 min. at 15atm.pressure. These medium were poured into sterile Petri plates and the organisms were inoculated after cooling the Petri plates. The percentage inhibition for fungi was calculated after five days using the formula given below: Percentage of inhibition = 100(X-Y) / X Where, X = Area of colony in control plate and Y = Area of colony in test plate Results and Discussion The synthesis of the novel 2,2'-(4,4'-(1,2-phenylenebis(diazene-2,1-diyl))bis(4,1-phenylene) )bis (azanediyl) bis (oxomethylene)dibenzoic acid(OPDAL)has not been reported previously. The ligand OPDAL was isolated in the form of a dark brown crystalline powder. It was soluble in DMF, dioxane, acetone, acetic acid and dilute hydrochloric acid. The important IR spectral features are a broad band extending from 3200-3600 cm-1 OH of COOH. The band around 1690 cm may due to carbonyl group. The bands around 1660, 3400 cm-1 may bedue to amide group. The strong band at 1625 cm-1 may be due to N=N group. The others bands are at their respective positions. The NMR data of OPDAL shown in experimental part are also confirming the structure of OPDAL. The co-ordination polymers derived from OPDAL were insoluble in common organic solvents. Hence, it is not possible to characterized the co-ordination polymers by molecular mass using conventional methods like osmometry, viscometry etc. These co-ordination polymers did not melt up to 360°C.Examination of the metal content in the polymers (Table-1) revealed that the 1:1 metal: ligand (M: L) stoichiometry for all the polymers. Comparison of the IR spectrum of the ligand OPDAL and those of the co-ordination polymers reveals certain characteristic differences. The broad band at 3400-3100 cm-1 for OPDAL has virtually disappeared for the spectra of polymers. However the weak bands around 3200 cm-1 in the spectra of OPDAL.Co2+, OPDAL.Ni2+OPDAL.Mn2+ indicate the presence of water molecules which may have been strongly absorbed by the polymer sample. An indication of this aspect is made later. The weak band around 1110 cm-1 is attributed to the C-O-M stretching frequency. The band at 1430 cm-1 in the IR spectrum of OPDAL is attributed to the in-plane OH deformation23. The band is shifted towards higher frequency in the spectra of the polymers indicating formation of metal-oxygen bond. These feature suggest that the structure of the co-ordination polymer (table-3).Table-1 Non-aqueous Conductometric titration of Estimation of – COOH groups Ligand Molecular weight gm Millimoles of TBAH at break per 100 gm of sample Estimated No. of –COOH group OPDAL 612 331 2.02 Solvent: Anhydrous pyridine. Reagent: 0.1 N tetra-n-butyl ammonium hydroxide (TBAH) in pyridine Research Journal of Chemical Sciences ___________________________________________________________ ISSN 2231-606XVol. 3(1), 48-56, January (2013) Res. J. Chem. Sci. International Science Congress Association 51 Table-2 Analytical and Spectral Data of the Co-Ordination Polymers of OPDAL Compound (Empirical Formula) Formula Weight Analyses % Found (Calculated) Mn ) + 60 % Yeild Dp %M %C %H %N OPDAL (C 34 H 24 N 6 O 6 ) 612 - 66.4 (66.67) 3.7 (3.92) 13.5 (13.73) - 76 - [Cu(OPDAL)(HO)n (Cu.C 34 H 22 N 6 O 6 .2H 2 O) 709.54 8.7 (8.95) 57.4 (57.50) 3.5 (3.66) 11.7 (11.84) 4310 78 6 [Co(OPDAL)(HO)n (Co.C 34 H 22 N 6 O 6 .2H 2 O) 704.94 8.0 (8.36) 57.6 (57.87) 3.5 (3.68) 11.8 (11.91) 4287 79 6 [Ni(OPDAL)(HO)n (Ni.C 34 H 22 N 6 O 6 .2H 2 O) 704.71 8.1 (8.33) 57.7 (57.89) 3.6 (3.68) 11.8 (11.92) 4273 75 6 [Mn(OPDAL)(HO)n (Mn.C 34 H 22 N 6 O 6 .2H 2 O) 700.94 7.7 (7.83) 58.1 (58.20) 3.8 (3.70) 11.8 (11.98) 3550 73 5 [Zn(OPDAL)(HO)n (Zn.C 34 H 22 N 6 O 6 .2H 2 O) 711.38 9.0 (9.19) 57.1 (57.35) 3.5 (3.65) 11.7 (11.80) 3599 77 5 Table-3 FT-IR data of ligand OPDAL and its coordination polymersCompounds (C=C) (CONH) (COOH) (N=N) (M-O) OPDAL 1591 1675 3430 1646 - [Cu(OPDAL)(H 2 O) 2 ] n 1575 1669 3385 1633 595 [Co(OPDAL)(H 2 O) 2 ] n 1565 1641 3369 1621 591 [Ni(OPDAL)(H 2 O) 2 ] n 1571 1650 3375 1624 592 [Mn(OPDAL)(H 2 O) 2 ] n 1561 1632 3366 1608 589 [Zn(OPDAL)(H 2 O) 2 ] n 1590 1671 3400 1634 597 Figure-2 IR spectrum of compound A Research Journal of Chemical Sciences ___________________________________________________________ ISSN 2231-606XVol. 3(1), 48-56, January (2013) Res. J. Chem. Sci. International Science Congress Association 52 Figure-3 The H NMR spectrum of Compound A Figure-4 The 13C NMR spectrum of Compound A Research Journal of Chemical Sciences ___________________________________________________________ ISSN 2231-606XVol. 3(1), 48-56, January (2013) Res. J. Chem. Sci. International Science Congress Association 53 Magnetic moments (µeff) of polymeric chelates are given in table-2. The diffusion electronic spectrum of OPDAL.Cu+2 co-ordination polymers shows two broad bands around 15,552 cm-1and 22,753 cm-1.The first bands may be due to 2gtransition. While the second may be due to charge transfer. The first band shows structure suggestion a distorted octahedral structure for the OPDAL.Co2+ polymers. The higher value of eff of the OPDAL.Cu2+ polymer supports this view. The OPDAL.Ni2+ and OPDAL.Co2+ polymers give two absorption bands respectively at 14,779 and 22,752 cm-1 and at 15,655 and 22,111 cm-1 which can be assigned respectively to 2g1g(P), 1g1g(P) transitions. These absorption bands and the values of µeff indicate an octahedral configuration for the OPDAL.Ni2+and OPDAL.Co2+ Polymers (table-4). The typical conductometric titration curve of OPDAL ligand reveal that, the two breaks observed the all curve. From the value of at second break the number of –COOH group for ligand has been calculated. It was found that the value of carboxylic group is about 2 the ligand. The TGA data for the polymers are presented in Table-5. The weight loss of the polymer samples at different temperatures indicates that the degradation of the polymers is noticeable beyond 300°C. The rate of degradation becomes a maximum at a temperature lying between 400°C and 500°C depending upon the nature of the polymers. Each polymer lost about 55% of its weight when heated up to 600°C. Inspection of the thermograms of OPDAL.Co2+, OPDAL.Mn2+ and OPDAL.Ni2+ samples revealed that these samples suffered appreciable weight loss in the range 150 to 280°C. This may due to the presence of water strongly absorbed by the polymers. It has also been indicated earlier that the IR spectra of these three polymer samples have OH bands at around 3200 cm-1 due to associated water. The ligand containing two –COOH groups. Hence the TGA of ligand in air may cause decarboxylation24. Examination of these data reveals that the decarboxylation of ligand consistent with the calculated values. All these facts confirm the structure of ligand. On the basis of the relative decomposition (% wt. loss) and the nature of thermograms, the co-ordination polymers may be arranged in order in increasing stability as: Cu Ni Co Mn This trend also coincides with the stability order already reported for the metal oxinates and for co-ordination polymers of OPDAL25. The antimicrobial activity of OPDAL and its coordination polymers are presented in Table-6 and 7. The data suggest that all the samples are toxic to bacteria or fungus. The data also suggest that the percentage of bacteria or fungus is inhibited in the range of 63 to 85% depending upon the biospecies and coordination polymers. All the polymers have good microbicidal activity. Figure-5 IR spectrum of compound (OPDAL) Research Journal of Chemical Sciences ___________________________________________________________ ISSN 2231-606XVol. 3(1), 48-56, January (2013) Res. J. Chem. Sci. International Science Congress Association 54 Figure-6 The 13H NMR spectrum of Compound (OPDAL) Figure-7 The 13C NMR spectrum of Compound (OPDAL) Figure-8 The Mass spectrum of Compound (OPDAL) Research Journal of Chemical Sciences ___________________________________________________________ ISSN 2231-606XVol. 3(1), 48-56, January (2013) Res. J. Chem. Sci. International Science Congress Association 55 Figure-9 IR Spectrum of [Cu(OPDAL)(HO)Table-4 Reflectance spectral and magnetic moment data of the ligand OPDAL containing coordination polymersCoordination Polymers Absorption band(cm-1) Transitions Magnetic moment(eff) BM [Cu(OPDAL)(HO)22753 15552 2 Eg 2 2gcharge transfer 1.89 [Co(OPDAL)(HO)15655 22111 4 1g(F) 4 2g 1g (F) 2g (P) 2.98 [Ni(OPDAL)(HO)14779 22752 3 2g 3 1g(F) 2g  3T 1g (P) 4.17 [Mn(OPDAL)(HO)15709 17473 22708 6 1g 4 1g(4G) 1g2g(4G) 1g  4A 1g , Eg 4.98 *Zn- containing polymers are diamagnetic in nature Table-5 TGA data of OPDAL containing coordination polymers Co-ordination polymers % Weight loss at different temperature( O C) 100 200 300 400 500 600 [Cu(OPDAL)(H 2 O) 2 ] n 2.6 4.8 13.3 42.6 47.5 53.5 [Co(OPDAL)(H 2 O) 2 ] n 3.9 8.7 16.7 21.7 43.3 59.6 [Ni(OPDAL)(H 2 O) 2 ] n 4.6 8.5 14.6 27.4 45.1 59.2 [Mn(OPDAL)(H 2 O) 2 ] n 4.4 6.7 9.9 15.7 25.2 36.5 [Zn(OPDAL)(H 2 O) 2 ] n 2.2 3.6 4.8 15.2 23.4 35.6 Table-6 Antibacterial Activities of Co-Ordination Polymers Zone of Inhibition Compounds Gram +Ve Gram –Ve Bacillus subtilis Staphylococcus aureus Salmonella typhi E.coli [Cu(OPDAL)(H 2 O) 2 ] n 61 65 72 73 [Co(OPDAL)(H 2 O) 2 ] n 62 70 63 71 [Ni(OPDAL)(H 2 O) 2 ] n 67 68 70 79 [Mn(OPDAL)(H 2 O) 2 ] n 60 72 81 84 [Zn(OPDAL)(H 2 O) 2 ] n 61 68 77 72 Research Journal of Chemical Sciences ___________________________________________________________ ISSN 2231-606XVol. 3(1), 48-56, January (2013) Res. J. Chem. Sci. International Science Congress Association 56 Table-7 Antifungal Activities of Co-Ordination Polymers Compounds Penicillium expansum Nigrospora Sp. Trichothesium Sp. Rhizopus nigricum [Cu(OPDAL)(H 2 O) 2 ] n 72 78 60 63 [Co(OPDAL)(H 2 O) 2 ] n 61 62 62 70 [Ni(OPDAL)(H 2 O) 2 ] n 72 71 65 73 [Mn(OPDAL)(H 2 O) 2 ] n 70 73 79 75 [Zn(OPDAL)(H 2 O) 2 ] n 54 69 72 74 Conclusions The 4,4'-(1,2-phenylenebis(diazene-2,1-diyl))dianiline and phthalic anhydride was react and afforded novel bisazo ligand namely 2,2'-(4,4'-(1,2-phenylenebis(diazene-2,1-diyl))bis(4,1-phenylene) )bis(azanediyl) bis(oxo methylene) dibenzoic acid(OPDAL).The novel bis azo ligand made complexes with different transition metal. The ligand coordinating through the carboxylic oxygen and the amide carbonyl group. The lignad and its metal complexes show good thermal stability. The Ligand and its metal complexes also show good microbicidal activity. References 1. Shukla H.M., Shah A.I., Shah P.J. and Raj D.S., Studies on synthesis, characterization and antibacterial screening of coordination polymers, J. Chem. Pharm. Res.,2(5), 169 (2010)2. Maho K., Shintaro T., Yutaka K., Kazuo W., Toshiyuki N. and Mosahiko T., Experimental Study of High-Density Rewritable Optical Disk Using a Blue-Laser Diode, J Appl Phys., 42, 1068 (2003) 3. Horowitz H. and Perrors J.P., Thermal stability of bis (8-hydroxy-5- quinolyl)-methane co-ordination polymers, J.Inorg Nucle.Chem.,26, 139-159 (1964) 4. Patel K.D., Panchani S.C., Coordination Polymers of 4, 4’ (8- Quinolinolyl -5 - methylenoxy)) diphenyl sulfide , Ultra Scientist Physical Science., 15, 195 (2003) 5. Patel H.S., Dixit R.B. and Shah T.B., Coordination Polymers of 1,6-bis(8-hydroxyquinolin-5-yl)-2,5-dioxa-3-methyl hexane , Int. J Polym Material., 49, 27 (2001) 6. Patel A.D., Patel R.S. and Patel G.R.,Coordination Polymers of N, N-di-(8-Hydroxyquinolinolyl- 5- methyl)-N, N-diethyl-1,3-propane diamine (QEPD), E-Journal of Chemistry.,7(3),1023(2010) 7. Patel K.D. and Patel H.S., Studies of the Coordination Polymers Based on Divalent Transition Metal Ion with Bis ligands, Der Pharmacia Lettre.,3(1), 356 (2011) 8. Shah A.I., Shukla H.M., Shah P.J., Raj D.S., Co-ordination polymers of heteronuclear bisligand, Der Chemica Sinica,1(3),70 2010) 9. Shah T.B., Patel H.S. and Dixit R.B., Co-ordination Polymers of 1,6-bis(8-hydroxyquinolin-5-yl)-2,5-dioxa-3-methyl hexane,Intern J Polymeric Mater.,49, 271 (2001) 10. Kaliyappan T. and Kannan P., Co-ordination polymers, Prog Polym Sci.,25(3), 343-370 (2000) 11. Dixit B.C., Dixit R.B. and Desai D.J., Synthesis and characterization of novel ion-exchange resin based on polyimide containing 8-hydroxyquinoline as a pendent groups ,Journal of Polymer Research., 17(4), 481 (2010) 12. Shah A.I., Shukla H.M., Shah P.J., Raj D.S., Der Pharmacia Sinica,1(3), 165 (2010) 13. Patel K.D. and Panchani S.C., Ulter of Phy Science, 15, 195 (2003) 14. Patel H.S., Dixit R.B. and Shah T.B., Co-ordination Polymers of 1,6-bis (8-hydroxyquinolin-5-yl)-2,5-dioxa-3-methyl hexane, Int. J Polym Material.,49, 27(2001) 15. Patel D.C., PhD. Thesis HNGU., Patan, (2007) 16. Shah A.I., Shukla H.M., Shah P.J. and Raj D.S.,Novel co-ordination polymers of 8-hydroxyquinoline, Elixir Chem. Phys., 44, 7378 (2012) 17. Rana A.K., Shah N.R., Karampurwala A.M. and Shah JR., Makromol Chem., Polychelates derived from 4, 4’-(4,4’-biphenylylenebisazo)di(salicylaldehyde oxime), 182(12), 3371 (1981) 18. Raj D.S., Co-ordination polymers based on Mixed Bis –Ligand 5-(3-Acetyl-4-Hydroxy-1-phenylazo)-8-Quinolinol(AHPQ),Research Journal of Chemistry and Environment.,5(1),35(2001)19. Singh A. and Bhanderi J., poly (ester-amide) having pendent 8-quinolinol moiety as a novel polymeric ligand, Rasayan J.Chem., 2(4), 846 (2009) 20. Charles R.G. and Langer A Heat Stabilities and Volatilities of Some Metal Chelates Derived from 8-Hydroxyquinoline 63, 603–605 (1959) 21. Vogel A.I., A Textbook of Quantitative Chemical Analysis Revised by Bessett J, Denny R.C., Feffery J.H. and Mondhaus J. , ElBS, 5th Edn London (1996) 22. Charles R.G., Freiser H., Priedel R., Hilliand L.E. and Johnston R.D.) Infra-red absorption spectra of metal chelates derived from 8-hydroxyquinoline, 2-methyl-8-hydroxyquinoline and 4-methyl-8-hydroxyquinoline, Spectrochim Acta., 8, 1 (1958) 23. Shah T.B., Patel H.S., Dixit R.B. and Dixit B.C., Coordination Polymers of 1,8-Bis (8-Hydroxyquinolin-5-yl)-2,7-Dioxaoctane, Int.J of Polym .Anal and Charact.,8, 369 (2003) 24. Parekh H., Ph.D. Thesis, Veer Narmad South Gujrat University, (2006) 25. Jani D.H., Patel H.S., Keharia H. and Modi C.K., Novel drug-based Fe(III) heterochelates: synthetic, spectroscopic, thermal and in-vitro antibacterial significance, Appl Org Chem.,24, 99 (2010)