Synthesis and characterization of new macrocycles containing pendant groups

Article abstract of DOI:10.1081/SIM-120028305

The new ligands, 1,5,8,12-tetraaza-4-(1′,1′-dimethylethyl)-2- (1″,1″,2″, 2″,3″,3″,3″- heptafluoropropyl)-9,11-(dimethyl)-cyclotetradeca-1,4,8,11-tetraene (L ¹) and 1,5,9,13-tetraaza-4-(1′,1′-dimethylethyl)-2- (1″,1″,2″, 2″,3″,3″,3″- heptafluoropropyl)-10,12-(dimethyl)-cyclohexadeca-1,4,9,12-tetraene (L ²), have been prepared by the reaction of 1,1,2,2,3,3,3-heptafluoro- 7,7-dimethyl-4,6-octanedione with ethylenediamine and acetyl acetone (L ¹) and 1,1,2,2,3,3,3-heptafluoro-7,7-dimethyl-4,6-octanedione with 1,3-diaminopropane and acetylacetone (L²), respectively. Their complexes with Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), and Zn(II) ions have also been synthesized and characterized by elemental analyses, magnetic susceptibility measurements, molar conductance measurements, IR, EPR, ¹H NMR, and UV-Visible spectra. The molar conductance values show that the complexes of Fe(III) and Cr(III) are 1:1 electrolytes, the Ni(II) and Cu(II) complexes are 1:2 electrolytes while those of Mn(II), Co(II), and Zn(II) appear to be non-ionic. An octahedral structure has been proposed for all of these metal ions except for those of Cu(II) and Ni(II), which appear to be square-planar. The β values indicate a considerable orbital overlap in the metal-ligand bond. All of the compounds have been tested against gram-positive bacteria of Staphylococcus aureus and gram-negative bacteria of Escherichia coli. The results show that these compounds inhibit the growth of bacteria.