Monomeric thorium chalcogenolates with bipyridine and terpyridine ligands

Area of Science:

• Organometallic Chemistry
• Coordination Chemistry
• Materials Science

Background:

• Thorium chalcogenolates are versatile precursors in organometallic synthesis.
• 2,2 -bipyridine is a common chelating ligand used to stabilize metal complexes.

Purpose of the Study:

• To synthesize and characterize new thorium chalcogenolate complexes with 2,2 -bipyridine.
• To investigate the structural, spectroscopic, and thermal properties of these complexes.

Main Methods:

• Synthesis of thorium chalcogenolate complexes.
• Spectroscopic characterization (e.g., 77Se NMR).
• Low-temperature single crystal X-ray diffraction.

Main Results:

• Four new complexes of the type (bipy)2Th(ER)4 were successfully synthesized and characterized.
• Structural analysis revealed significant conformational flexibility of the chalcogenolate ligands.
• The selenolate complexes showed structural consistency between solid-state and solution phases.
• The first terpyridine-thorium complex, (terpy)(py)Th(SPh)4, was isolated.
• The complexes exhibited thermochromism due to ligand-to-ligand charge transfer.

Conclusions:

• The reaction of thorium chalcogenolates with 2,2 -bipyridine yields stable complexes with flexible ligand environments.
• These thorium complexes represent a new class of thermochromic materials with potential applications in sensing or display technologies.