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Synthesis of a Thiol Building Block for the Crystallization of a Semiconducting Gyroidal Metal-sulfur Framework
Published on: April 9, 2018
Titanium(IV) complexes of disulfide-linked Schiff bases
Alberto Donzelli1, Imir Metushi, Pierre G Potvin
1Department of Chemistry, York University, 4700 Keele Street, Toronto, Ontario, Canada M3J 1P3.
Inorganic Chemistry
|April 21, 2012
Summary
Researchers synthesized novel titanium(IV) complexes with Schiff-base ligands for potential use in electrocatalysis. Unexpected mononuclear macrocyclic structures were formed, exhibiting useful oxidation potentials but limited reduction activity.
Area of Science:
- Coordination Chemistry
- Organometallic Chemistry
- Electrocatalysis
Background:
- Titanium(IV) complexes are explored for catalytic applications.
- Sulfur-based redox-active ligands offer unique electronic properties.
- Schiff-base ligands are versatile in coordinating metal centers.
Purpose of the Study:
- To synthesize and characterize novel titanium(IV) complexes with sulfur-based Schiff-base ligands.
- To investigate the structural and electrochemical properties of these complexes.
- To evaluate their potential for electrocatalytic alcohol oxidation.
Main Methods:
- Reaction of Ti(OR)4 with 2,2'-dithiodianiline Schiff-base derivatives.
- Crystallographic analysis to determine molecular structure.
- Cyclic voltammetry to assess electrochemical behavior.
Main Results:
- Mononuclear titanium(IV) species LTi(OR)2 were unexpectedly obtained instead of dimeric products.
- Crystallography revealed an unprecedented symmetrical macrocyclic arrangement with four-point ligand binding.
- Complexes showed useful oxidation potentials (1.1-1.5 V vs Ag/AgCl) but limited reduction activity.
Conclusions:
- The synthesis yielded unique mononuclear titanium(IV) macrocycles with uncoordinated disulfide moieties.
- The observed structures and electrochemical properties provide insights into ligand design for titanium complexes.
- Further modifications may be needed to enhance the reduction capabilities for broader electrocatalytic applications.
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