SYNTHESIS AND CHARACTERIZATION OF A CROWN-ETHER SUBSTITUTED SALICYLALDIMINE AND ITS COMPLEXES WITH COPPER(II), COBALT(II), NICKEL(II), AND URANYL(VI)

4'-(omega-Salicylaldiminoacetyl)benzo (15-crown-5) (LH) has been synth esized from 4'-(omega-aminoacetyl)benzo(15-crown-5) and salicylaldehyd e. Complexes of this Schiff base with copper(II), nickel(II), cobalt(I I), and uranyl(VI) have been prepared from the corresponding metal ace tates and chlorides. Insertion of sodium ions into the crown ether-moi ety has been accomplished by refluxing LH with sodium nitrate in ethan ol. The complexation of this ligand with Cu(II), Ni(II), Co(II), and U (VI)O-2 was investigated by potentiometric titration; the results indi cate that all of them afford products with a metal-ligand ratio of 1:2 . The order of formation constants of the mononuclear complexes is Cu( II) > Co(II) > U(VI)O-2 > Ni(II).