Si(SiMe3)2SiPh3 - a ligand for novel sub-valent tin cluster compounds

Area of Science:

• Organometallic Chemistry
• Main Group Chemistry
• Materials Science

Background:

• Silyl ligands, particularly symmetric ones like Si(SiMe3)3, are crucial for synthesizing metalloid tin cluster compounds via Sn(I) halide disproportionation.
• Asymmetric silyl ligands with lower symmetry remain largely unexplored for this application.

Purpose of the Study:

• To synthesize and characterize a novel asymmetric silyl ligand, [Si(SiMe3)2(SiPh3)]-.
• To investigate the utility of this new ligand in the synthesis of subvalent tin compounds.

Main Methods:

• Synthesis of potassium and lithium salts of the silanide [Si(SiMe3)2(SiPh3)]-.
• Reaction of the silanide with tin halides SnCl2 and SnCl.
• Isolation and characterization of the resulting tin compounds.

Main Results:

• The asymmetric silanide [Si(SiMe3)2(SiPh3)]- was synthesized in excellent yield.
• Reactions with SnCl2 yielded the stannide [Sn(Si(SiMe3)2SiPh3)2Cl]-.
• Reactions with SnCl unexpectedly produced the ring compound Cl4Sn4[Si(SiMe3)2SiPh3]4, with no elemental tin observed.

Conclusions:

• The asymmetric silanide [Si(SiMe3)2(SiPh3)]- is a viable precursor for subvalent tin chemistry.
• This ligand facilitates the formation of novel tin cluster compounds and stannides.
• The absence of elemental tin suggests the potential presence of metalloid tin clusters in solution.