A Dimeric NHC-Silicon Monotelluride: Synthesis, Isomerization, and Reactivity

Area of Science:

• Organometallic Chemistry
• Silicon Chemistry
• Main Group Chemistry

Background:

• N-Heterocyclic Carbene (NHC) stabilized silicon complexes offer unique reactivity.
• Elemental chalcogens like tellurium and sulfur are crucial for synthesizing novel inorganic compounds.
• Understanding the reactivity of low-valent silicon species is key to expanding inorganic synthesis.

Purpose of the Study:

• To investigate the reaction of an NHC-disilicon(0) complex with elemental tellurium.
• To synthesize and characterize novel NHC-stabilized silicon-telluride complexes.
• To explore the formation of dimeric silicon ditelluride and sulfur ditelluride compounds.

Main Methods:

• Reaction of [(I_Ar )Si=Si(I_Ar )] with elemental tellurium in toluene under varying conditions.
• Isolation and characterization of reaction products using spectroscopic and analytical techniques.
• Exploration of subsequent reactions with elemental sulfur to form mixed chalcogen complexes.

Main Results:

• The reaction yielded the first dimeric NHC-silicon monotelluride, [(I_Ar )Si=Te]₂, and its isomer.
• Extended reaction times and stoichiometry led to the formation of dimeric NHC-silicon ditelluride, [(I_Ar )Si(=Te)(μ-Te)]₂.
• The first NHC-disilicon sulfur ditelluride complex, [{(I_Ar )Si(=Te)}₂ S], was synthesized from an intermediate.

Conclusions:

• The NHC-disilicon(0) complex serves as a versatile precursor for synthesizing novel silicon-chalcogen compounds.
• Reaction conditions, including time and stoichiometry, significantly influence the product distribution.
• This study expands the known chemistry of NHC-stabilized silicon complexes with heavier chalcogens.