Mesoionic Dithiolates (MIDts) Derived from 1,3-Imidazole-Based Anionic Dicarbenes (ADCs).

Area of Science:

• Organometallic Chemistry
• Main Group Chemistry
• Ligand Design

Background:

• Mesoionic compounds represent a unique class of heterocyclic compounds with delocalized charge.
• Anionic dicarbenes are versatile precursors in coordination and organometallic chemistry.
• The development of novel ligands is crucial for advancing the synthesis of new inorganic and organometallic compounds.

Purpose of the Study:

• To synthesize novel mesoionic dithiolate ligands from anionic dicarbenes.
• To explore the coordination chemistry of these ligands with germanium.
• To characterize the resulting germanium complexes and investigate their electronic structures.

Main Methods:

• Synthesis of mesoionic dithiolates via reaction of anionic dicarbenes with elemental sulfur.
• Complexation reactions with germanium dichloride precursors.
• Characterization using spectroscopic methods (NMR, IR, etc.) and single-crystal X-ray diffraction.
• Computational analysis using Density Functional Theory (DFT) calculations.

Main Results:

• Readily accessible synthesis of mesoionic dithiolate ligands [(MIDtAr)Li(LiBr)2(THF)3] and [(MIDtPh)Li(THF)2] in high yields (>90%).
• Formation of a three-coordinate germylene complex, (MIDtPh)GeCl, from the reaction of [(MIDtPh)Li(THF)2] with (L)GeCl2.
• Synthesis of a Ge-Ge catenation product, (MIDtPh)GeGeCl3, and a homoleptic germylene, (MIDtPh)2Ge, through further reactions and reduction.

Conclusions:

• Mesoionic dithiolates are effective ligands for stabilizing reactive germanium species.
• The synthesized germanium complexes exhibit unique coordination environments and bonding.
• DFT calculations provide insights into the electronic structures of the novel germanium compounds.