Copper(II) and Zinc(II) Complexes Synthesized by Green Mechanochemical Method and their Antimicrobial Studies


  • S. Sani Usmanu Danfodiyo University, P.M.B. 2346, Sokoto, Nigeria
  • I. T Siraj Bayero University Kano, P.M.B 3011, Kano, Nigeria


Mechanochemistry, Schiff base, azomethine, complexes, antimicrobial activity


Communication in Physical Sciences, 2021, 7(2):67-75

Authors: Sani* and I. T Siraj

Received 15 April 2021/Accepted 07 May 2021

Schiff base ligand derived from condensation of 2-hydroxy-1-naphthaldehyde and 2-aminobenzothiazole were synthesized via mechanochemical technique and used for the preparation of Cu(II) and Zn(II) complexes. The Schiff base and complexes were characterized by infrared spectroscopy, powder x-ray diffraction, Thermogravitric/thermal analysis, CHN analysis, solubility test, conductivity measurement and magnetic susceptibility measurement. Infrared spectral study indicated a strong band in the spectra of the Schiff base at 1603 cm-1 assigned to azomethine stretching vibration. The azomethine band shifted to 1621 and 1599 cm-1 in the IR spectra of Cu(II) and Zn(II) complexes respectively indicating the formation of complex compounds. The decomposition temperatures of the complexes are in the range of 240 - 264 oC indicating good thermal stability. Molar conductance values are in the range of 6.34 - 9.8 Ohm-1cm2 mol-1, indicating non electrolytic nature of the synthesized complexes in ethanol. Magnetic susceptibility measurement indicated that Zn(II) complex is diamagnetic while Cu(II) complex is  paramagnetic and exhibit magnetic moment of 2.059 BM, the values correspond to the square planar geometry. The theoretical and experimental analytical data of C, H and N for the Schiff base and complexes are in good agreement. The Schiff base ligand and metal complexes have been studied for microbial activity using pathogenic bacteria (Escherichia coli and Staphylococcus aureus) and fungal pathogens (Candida albican and Asperigillus fumigatus) by agar well diffusion method. The results indicated that metal complexes (07 - 19 mm diameter inhibition zones) are more active than Schiff base ligand (07 - 14 mm diameters) against the test organisms.


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Author Biographies

S. Sani , Usmanu Danfodiyo University, P.M.B. 2346, Sokoto, Nigeria

Department of Pure and Applied Chemistry

I. T Siraj , Bayero University Kano, P.M.B 3011, Kano, Nigeria

Department of Pure and Industrial Chemistry


Amrute, A. P., De Bellis, J., Felderhoff, M. & Schuthm F. (2021). Mechanochemical synthesis of catalytic materials. Chemistry: A European Journal, 27, 23, pp. 6815-6994

Bowmaker, G. A., Chaichit, N., Pakawatchai, C., Skelton, B. W., & White, A. H. (2008). Solvent-assisted mechanochemical synthesis of metal complexes. Dalton Transactions, 22, pp. 2926–2928.

Carabineiro, S. A., Silva, L. C., Gomes, P. T., Pereira, L. C., Veiros, L. F., Pascu, S. I., Duarte, M. T., Namorado, S., & Henriques, R. T. (2007). Synthesis and characterization of tetrahedral and square planar bis (iminopyrrolyl) complexes of cobalt (II). Inorganic Chemistry, 46, 17, pp. 6880–6890.

Chakravarty, R., & Banerjee, P. C. (2012). Mechanism of cadmium binding on the cell wall of an acidophilic bacterium. Bioresource Technology, 108, pp. 176–183.

Chieng, N., Rades, T., & Aaltonen, J. (2011). An overview of recent studies on the analysis of pharmaceutical polymorphs. Journal of Pharmaceutical and Biomedical Analysis, 55, 4, pp. 618–644.

Cinčić, D., & Kaitner, B. (2011). Schiff base derived from 2-hydroxy-1-naphthaldehyde and liquid-assisted mechanochemical synthesis of its isostructural Cu (II) and Co (II) complexes. CrystEngComm, 13, 13, pp. 4351–4357.

Cindrić, M., Uzelac, M., Cinčić, D., Halasz, I., Pavlović, G., Hrenar, T., Ćurić, M., & Kovačević, D. (2012). Three routes to nickel (II) salicylaldehyde 4-phenyl and 4-methylthiosemicarbazonato complexes: Mechanochemical, electrochemical and conventional approach. CrystEngComm, 14, 9, pp. 3039–3045.

Fernandez-Bertran, J., & Reguera, E. (1996). Mechanochemical reactions in alkali halide pressed disks. Solid State Ionics, 93, 1-2, pp. 139–146.

Fitzgerald, R. J., & Brubaker, G. R. (1969). Contact shift studies of the square-planar complex bis (dithioacetylacetonato) cobalt (II). Inorganic Chemistry, 8, 11, pp. 2265–2267.

Friščić, T. (2010). New opportunities for materials synthesis using mechanochemistry. Journal of Materials Chemistry, 20, 36, pp. 7599–7605.

Friščić, T. (2012). Supramolecular concepts and new techniques in mechanochemistry: Cocrystals, cages, rotaxanes, open metal–organic frameworks. Chemical Society Reviews, 41, 9, pp. 3493–3510.

Friscic, T., & Jones, W. (2009). Recent advances in understanding the mechanism of cocrystal formation via grinding. Crystal Growth and Design, 9, 3, pp. 1621–1637.

Gennari, F. C., & Andrade-Gamboa, J. J. (2018). Chapter 13 - A systematic approach to the synthesis, thermal stability and hydrogen storage properties of rare-earth borohydrides, Editor(s): Cheong, K. Y., Impellizzeri, G. and Fraga, M. A. (2018). Emerging Materials for Energy Conversion and Storage, Elsevier,.

James, S. L., Adams, C. J., Bolm, C., Braga, D., Collier, P., Friščić, T., Grepioni, F., Harris, K. D., Hyett, G., & Jones, W. (2012). Mechanochemistry: Opportunities for new and cleaner synthesis. Chemical Society Reviews, 41, 1, pp. 413–447.

Jayanthi, K., Meena, R. P., Chithra, K., Kannan, S., Shanthi, W., Saravanan, R., Suresh, M., & Satheesh, D. (2017). Synthesis and microbial evaluation of copper (II) complexes of Schiff base ligand derived from 3-methoxysalicylaldehyde with semicarbazide and thiosemicarbazide. J. Pharm Chem Bio Sci, 5, 1, pp. 205–215.

Joseyphus, R. S., Dhanaraj, C. J., & Nair, M. S. (2006). Synthesis and characterization of some Schiff base transition metal complexes derived from vanillin and L (+) alanine. Transition Metal Chemistry, 31, 6, pp. 699–702.

Kalia, S. B., Lumba, K., Kaushal, G., & Sharma, M. (2007). Magnetic and spectral studies on cobalt (II) chelates of a dithiocarbazate derived from isoniazid.

Kubaisi, A. A., & Ismail, K. Z. (1994). Nickel (II) and palladium (II) chelates of dehydroacetic acid Schiff bases derived from thiosemicarbazide and hydrazinecarbodithioate. Canadian Journal of Chemistry, 72, 8, pp. 1785–1788.

Nakamoto, K. (2006). Infrared and R aman Spectra of Inorganic and Coordination Compounds. Handbook of Vibrational Spectroscopy.

Nejo, A. A., Kolawole, G. A., & Nejo, A. O. (2010). Synthesis, characterization, antibacterial, and thermal studies of unsymmetrical Schiff-base complexes of cobalt (II). Journal of Coordination Chemistry, 63, 24, pp. 4398–4410.

Nishat, N., Hasnain, S., Ahmad, T., & Parveen, A. (2011). Synthesis, characterization, and biological evaluation of new polyester containing Schiff base metal complexes. Journal of Thermal Analysis and Calorimetry, 105, 3, pp. 969–979.

Sakıyan, I., Logoglu, E., Arslan, S., Sari, N., & Şakiyan, N. (2004). Antimicrobial activities of N-(2-hydroxy-1-naphthalidene)-amino acid (glycine, alanine, phenylalanine, histidine, tryptophane) Schiff bases and their manganese (III) complexes. Biometals, 17, 2, pp. 115–120.

Sani, S., Kurawa, M. A., Siraj, I. T., & Koki, I. B. (2019). Mechanochemical synthesis: A suitable method to the synthesis of some diamines Schiff bases. Bayero Journal of Pure and Applied Sciences, 12, 1, pp. 90–96.

Shaker, S. A., Aziz, Y. F. A., & Salleh, A. A. (2009). Synthesis and Characterization of Mixed Ligand Complexes of 8-Hydroxyquinoline and o-hydroxybenzylidene-1-phenyl-2, 3-dimethyl-4-amino-3-pyrazolin-5-on with Fe (II), Co (II), Ni (II) and Cu (II) ions. European Journal of Scientific Research, 33, 4, pp. 702–709.

Shan, N., Toda, F., & Jones, W. (2002). Mechanochemistry and co-crystal formation: Effect of solvent on reaction kinetics. Chemical Communications, 20, pp. 2372–2373.

Siraj, I. T., & Kurawa, M. A. (2020). Green Synthesis of Nickel (II) and Zinc (II) Complexes of Bis (Imine) Schiff base Derived from o-vanilline and m-phenylenediamine. International Journal of Chemical Synthesis and Chemical Reactions, 6, 1, pp. 31–43.

Stilinović, V., Cinčić, D., Zbačnik, M., & Kaitner, B. (2012). Controlling solvate formation of a Schiff base by combining mechano-chemistry with solution synthesis. Croatica Chemica Acta, 85, 4, pp. 485–493.

Tas, E., Aslanoglu, M., Kilic, A., & Kara, Z. (2006). Synthesis, spectroscopic and electrochemical studies of copper (II) and cobalt (II) complexes of three unsymmetrical vic-dioximes ligands. Journal of Coordination Chemistry, 59, 8, pp. 861–872.

Tigineh, G. T., & Liu, L.-K. (2014). Studies on Mechanochemistry: Solid Coordination Compounds from Primary Aromatic Amines and Cobalt (II) Chloride Hexahydrate. Journal of the Chinese Chemical Society, 61, 11, pp. 1180–1187.

Vadivel, T., & Dhamodaran, M. (2016). Synthesis, characterization and antibacterial studies of ruthenium (III) complexes derived from chitosan Schiff base. International Journal of Biological Macromolecules, 90, pp. 44–52.

Wang, F., Yao, J., Si, Y., Chen, H., Russel, M., Chen, K., Qian, Y., Zaray, G., & Bramanti, E. (2010). Short-time effect of heavy metals upon microbial community activity. Journal of Hazardous Materials, 173, 1-3, pp. 510–516.

Zaky, R., & Fekri, A. (2018). Solvent-free mechanochemical synthesis of Zn (II), Cd (II), and Cu (II) complexes with 1-(4-methoxyphenyl)-4-(2-(1-(pyridin-2-yl) ethylidene) hydrazinyl)-1H-pyrrole-3-carbonitrile. Green Processing and Synthesis, 7, 6, pp. 515–523.

Zhong, W., Zhong, G. Q., Zhang, Y., & Zhong, Q. (2012). Solvent-Free Synthesis and Characterization of the Zn (II) Complexes with Amino Acid Schiff Base. Advanced Materials Research, 455, pp, 740–745.