Self-assembled Transition Metal Coordination Frameworks of ...

Chapter 2 _. M_ _ up
1. Quinoline-2-c arbaldehyde N(4),N(4)-(butane-1,4-diyl) thiosemicarbazone
(HE)
2. 2-Benzoylpyridine-N(4),N(4)-(butane-1,4-diyl) thiosemicarbazone (HL*')
\N
\N s
/ /N HL7 8
Scheme 2.2. Thiosemicarbazone ligands with general atom numbering scheme.
The synthesis of H;L1 was reported [10] meagerly, without any spectral
studies. Synthesis and crystal structure of HQL2 have been reported simultaneously
[4,1]]. The spectral data for HQLZ was reinvestigated here for a comparison with that
of other compounds, as there were contradictions in the two reports [4,] l]. Also there
is a report of synthesis of I-l;L5 [4] but without much study. However, there are no
further reports of their coordination chemistry. The other two carbohydrazones and
thiocarbohydrazone H;L3 are new ligands. We have reported the synthesis and
structure of the ligand HQL4 [l6]. Synthesis and structural and spectral studies of
thiosemicarbazone HL8 and its iron(lIl) [I7], Cu(ll) [18] and Mn(Il) complexes [19]
have been reported from our laboratory. But their coordination towards other
transition metals like Ni(Il) haven’t reported. However. the ligand HL7 is a newly
synthesized one. The synthesis and studies of these thiosemicarbazone ligands are
found relevant as a supporting study. For studying their coordinating properties and
for a comparison with that of their higher homologue thiocarbohydrazone ligands also
prompted us to study these thiosemicarbazones.
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