Synthesis, characterization, thermal, catalytic and antimicrobial aspects of LnIII polymers of phenolic resins

Inorganic compounds of transition and inner transition metal ions play an important role in various chemical reactions. Calcium and lanthanides are similar in their chemical behavior, but nature has selected only calcium in various biochemical processes. Therefore Ln(III) metal ions inorganic coordination polymers have been selected for the study of antimicrobial and catalytic activity. In coordination polymers superior behavior, of united inorganic and organic moiety is observed as catalyst. It is superior to pure organic or inorganic material alone. Coordination polymers of HEAP-1,3-BD poly[(2-hydroxy-4-ethoxy acetophenone)-1,3-butylene)] with La-III, Pr-III, Nd-III, Sm-III, Gd-III, Tb-III and Dy-III metal ions have been synthesized and characterized by elemental analyses, electronic spectra, magnetic susceptibilities, FTIR, NMR, Scanning Electronic Microscopy (SEM) and thermogravimetric analyses. The metal ligand ratio is 1 : 2 in all the coordination polymers. High thermal stability of coordination poly chelates indicates their polymeric nature. Catalytic activity of selected coordination polymers was studied for important organic synthesis. It is found that polymer metal chelate complexes are efficient and effective catalyst in the Biginelli three component, one-pot synthesis of 3,4-dihydropyrimidin-2(1H)-ones. Antimicrobial activity of isolated Ln(III)-coordination polymers against Escherichia coli, Bacillus subtilis, Staphylococcus aureus (bacteria) and Saccharontyces cerevisiae (yeast) were measured. In compared to resin, polymer metal chelate complexes showed better antimicrobial activity. It was observed from the study that the Ln(III)-coordination polymers act as an efficient and effective catalysts and antimicrobial agents. The coordination polymers can be used as an economical and eco-friendly catalysts for selected organic synthesis with different aldehydes and beta-ketoesters.