FULL PAPER Green synthesis approach for novel benzenesulfonamide nanometer complexes with elaborated spectral, theoretical and biological treatments Jabir H. Al‐Fahemi 1 | Abdalla M. Khedr 1,2 | Ismail Althagafi 1 | Nashwa M. El‐Metwaly 1,3 | Fawaz A. Saad 1 | Hanadi A. Katouah 1 1 Department of Chemistry, Faculty of Applied Science, Umm Al‐Qura University, Makkah, Saudi Arabia 2 Chemistry Department, Faculty of Science, Tanta University, Tanta, Egypt 3 Chemistry Department, Faculty of Science, Mansoura University, Mansoura, Egypt Correspondence Nashwa M. El‐Metwaly, Department of Chemistry, Faculty of Applied Science, Umm Al‐Qura University, Makkah, Saudi Arabia; Chemistry Department, Faculty of Science, Mansoura University, Mansoura, Egypt. Email: n_elmetwaly00@yahoo.com New series of nano‐sized bi‐homonuclear Ce (III), ZrO (II), Sn (II), Pb (II), Cr (III), Fe (III) and Cu (II) complexes with 4‐[(2,4‐dihydroxybenzylidene)amino]‐ N‐(1,3‐thiazol‐2‐yl) benzenesulfonamide (H 3 L) were synthesized via green solid‐state method. The structural and molecular formulae of all synthesized complexes were established based on variable spectral, analytical and theoret- ical implementations. FT‐IR study confirms the coordination of H 3 L with metal ions through the Schiff base and sulfonamide centers in di‐basic tetra‐ dentate mode. Thermal analysis, magnetic moment and electronic spectra are attributing to octahedral configuration around Ce (III), Cr (III) and Fe (III) centers, while with ZrO (II), Sn (II), Pb (II) and Cu (II) centers, acquired tetra- hedral arrangement. TEM and XRD studies, represent the nanometer charac- ters of most metal ion complexes. TGA curves are utilized to compute the activation thermo‐kinetic parameters over different decomposition stages applying Coats‐Redfern method. Theoretical implementation executed by Gaussian09 program exerted the structures for the best atomic orientation over whole molecules. QSAR data were achieved over Hyper Chem 8.1 program through molecular mechanics process. Docking complexes between free ligand and different protein receptors were obtained through AutoDock Tools 4.2. Antimicrobial, antifungal and antitumor activities of the metal complexes were studied in comparing with free ligand to assert their potential therapeutic uses. H 3 L, Ce (III), Fe (III) and Cu (II) complexes displayed high antibacterial activ- ity near that of standard Gentamycin. Moreover, Cr (III) complex displayed highest cytotoxicity against human liver Carcinoma cell line (HEPG2). KEYWORDS bio‐efficiency, green synthesis, nanometer complexes, spectral, theoretical 1 | INTRODUCTION Lately much work has been done to synthesize significant compounds and nanomaterials comprising nanoparticles, nanorods, composites, clusters and transition metal complexes, applying solid state preparation method. [1,2] It is a straightforward and efficient method to prepare several functional materials and compounds. Advantages of solid‐ state reaction processes were much faster reaction rate, higher yield, being inexpensive, easier operating, energy Received: 19 March 2018 Revised: 2 May 2018 Accepted: 8 May 2018 DOI: 10.1002/aoc.4460 Appl Organometal Chem. 2018;e4460. https://doi.org/10.1002/aoc.4460 Copyright © 2018 John Wiley & Sons, Ltd. wileyonlinelibrary.com/journal/aoc 1 of 15