Mono-Chelates of Copper(II) with 5(3)-Methylpyrazole-3(5)-Carbohydrazide

Department of Pure Chemistry, University College of Science, Calcutta-700 009 Manuscript received 2 FebruarF 1981, revised 28 May 1981, accepted 22 July 1981 Mono-chelates of copper(ll) with 5(3)-methylpyrazole-3(5)-carbohydrazide (MPCH) have been synthesised and physico-chemically characterised. The llgamd MPCH primarily functions as a neutral (ONN) tridentate throngh the (pyrazolyl) riag nitrogen, the aminlc nitrogen and the amidic oxygen (of the hydrazide compunent) in forming the specles of empirical composition Cu(MPCH)X2,nH2O [X=CI, Br, CIO4 , NO3, BF4 or ½SO4 ; n=0 or 2]. Magnetic and spectral data indicate polymeric octahedral structures for these seemingly monomeric species, where the amidic nitrogen atom of tbe ligand in each monomer forms a bridge with its neighbouring unit through coordination to the Cu(II) ion of tbe adjacent molecule and thus the ligand behaves effectively u a tetradentate one