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Updated: Sep 24, 2025
Synthesis of a Thiol Building Block for the Crystallization of a Semiconducting Gyroidal Metal-sulfur Framework
Published on: April 9, 2018
Novel tetrahedral cobalt(ii) silanethiolates: structures and magnetism
Daria Kowalkowska-Zedler1, Natalia Nedelko2, Katarzyna Kazimierczuk1
1Department of Inorganic Chemistry, Faculty of Chemistry, Gdańsk University of Technology Narutowicza Str. 11/12 80-233 Gdańsk Poland agnieszka.pladzyk@pg.edu.pl.
Abstract:
Three heteroleptic complexes of Co(ii) tri-tert-butoxysilanethiolates have been synthesized with piperidine [Co{SSi(OtBu)3}2(ppd)2] 1, piperazine [Co{SSi(OtBu)3}2(NH3)]2(μ-ppz)·2CH3CN 2, and N-ethylimidazole [Co{SSi(OtBu)3}2(etim)2] 3. The complexes have been characterized by a single-crystal X-ray, revealing their tetrahedral geometry on Co(ii) coordinated by two nitrogen and two sulfur atoms. Complexes 1 and 3 are mononuclear, whereas 2 is binuclear. The spectral properties and thermal properties of 1-3 complexes were established by FTIR spectroscopy for solid samples and TGA. The magnetic properties of complexes 1, 2, and 3 have been investigated by static magnetic measurements and X-band EPR spectroscopy. These studies have shown that 1 and 3, regardless of the similarity in structure of CoN2S2 cores, demonstrate different types of local magnetic anisotropy. Magnetic investigations of 2 reveal the presence of weak antiferromagnetic intra-molecular Co(ii)-Co(ii) interactions that are strongly influenced by the local magnetic anisotropy of individual Co(ii) ions.
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