Preparation and spectroscopic characterization of polymer-supported transition metal complexes

Abstract

Novel polystyrene supported mixed Schiff base (PSCH2–LH2) and its coordination compounds with copper(II) and zirconium(IV) have been synthesized. PSCH2–LH2 has been synthesized by the reaction of chloromethylated polystyrene crosslinked with divinylbenzene (PSCH2–Cl) and the Schiff base (LH2) derived from 3-formylsalicylic acid, propylenediamine and acetylacetone. The polystyrene supported coordination compounds are of the types: [PSCH2–LCu] and [PSCH2–LZr(OH)2·DMF]. They have been synthesized by the reaction of PSCH2–LH2 and the metal salt in DMF. The coordination compounds have been characterized on the basis of elemental analyses, IR, reflectance, ESR spectral and magnetic susceptibility measurements. The shifts of the ν(C=N) (azomethine), ν(C–O) (phenolic) and ν(C–O) (enolic) stretches indicate the ONNO donor behaviour of PSCH2–LH2. The polystyrene supported Cu(II) compound is square planar and Zr(IV) compound is pentagonal bipyramidal. The coordinated solvent molecules are completely lost from metal bound coordination compound by heating them at definite temperature in an air oven for 3 h. The compound, PSCH2–LCu is paramagnetic, while PSCH2–LZr(OH)2·DMF is diamagnetic.