الفهرس 
Preparation of organic ligandsOnly 14 pages are availabe for public view
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Abstract
the statement of the problem is included. The work comprises three chapters, The first one deals with a general review on the coordinat ion chemistry and biological activity of the Schiff bases derived from thiosemicarbazide, hydrazine-S-methyl dithiocarboxylate and hydrazine-S-benzyl dithiocarboxylate and different aldehydes and ketones. The second chapter describes the methods of preparation of the Schiff bases, 2-picolyl phenyl ketone thiosemicarbazone (PPKTS), 2-picolyl phenyl ketone hydrazine-S-methyl ditiocarboxylate (PPKTE), 2-picolyl phenyl ketone hydrazine-S-benzyl dithiocarboxylate (PPKBZTE), 2,6-lutidyl phenyl ketone thioeemicarbazone (LPKTS), 2,6-lutidyl phenyl ketone hydrazine-Smethyl ditiocarboxylate (LPKTE) and 2,6-lutidyl phenyl ketone hydrazine-S-benzyl dithiocarboxylate (LPKBZTE). Also the methods of preparation of nickel (11) , copper(I1) , zinc (11) and cadmium(11) complexes are described. The elemental analyses and the different - physical techniques employed are discussed. The third chapter includes thg results and discussion .and consists of three parts. The first part deals with the infrared and nuclear magnetic resonance spectra of the Schiff ases and their rnetal(11) chelates. The infrared and ’H nmr spectral data suggested t h a t these Schiff bases act as neutral t r i d e n t a t e , monobasic t r i d e n t a t e or monobasic bidentate coordinated to the metal ion via the azometine and heterocyclic nitrogen atoms and the thiolo sulpher atom. The second part describes the e l e c t r o n i c s p e c t r a and the magnetic measurements of nickel(I~), zinc(I1) and cadmium(I1) complexes. ~inc(11) and cadmium(11) complexes of a l l Schiff bases are diamagnetic poossessing square planar geometry. ~ickel(11) complexes, [(PPKTS-H)N~*]x 2, X = C1, B r o r I are diamagnetic implying square planar environment around nickel (11) ion. Their molar conductivity measurements as IO-~M i n litrobenzene as solvent displayed conductivity values of 1 :2 ?lectrolytes. Therefore, the square planar geometry is achieved ria a bridged sulphur atom between two nickel(11) ions. These !omplexes gave bis-pyridine adducts having formula . {PPKTS-H)N~(P~)*X] , X = C1, B r or I, with octahedral stereohemistry. [(LPKTS-H)Ni] 2X2, X= C1, B r or I have room temperature 2gnetic moments of 1.23, 1.21 and 1.24 B.M. respectively. ieir variable temperature magnetic moments, molar conductivity td spectral data confirm the coexistance of a dimeric diamagbtic and a tetrameric paramagnetic nickel(11) species within e same unit c e l l . Their electronic s,pectra i n neet pyridine hibit spectral features c h a r a c t e r i s t i c of the octahedral ifiguration around nickel(I1) ion. The i n t e r a c t i o n of PPKTE ;h nickel (11) s a l t s afforded with I : 1 complexes of formula.