Jayswal et al.: A New Approach Towards Synthesis of Some Novel “Upper Rim ” ... Scientific paper A New Approach Towards Synthesis of Some Novel “Upper Rim ” Functionalized Calix[4]resorcinarene Schiff-bases

Synthesis of new “upper rim ” functionalized calix[4]resorcinarene Schiff-bases has been carried out by reacting tetra-aminocalix[4]resorcinarene with different aromatic aldehydes in ethanol at reflux temperature. The tetra-aminoca-lix[4]resorcinarene, which can serve as very good precursor for various derivatizations at the extra annular position, was synthesized for the first time through tetra-azo intermediate, by first introducing the azo functionality at the upper rim, and subsequent reduction with Na2S2O4 in aq. NaOH. Synthesized Schiff-bases were characterized by elemental analy-sis, FT-IR, NMR and Mass spectral data. Their complexation ability with Cu(II) is also investigated