Unsymmetrical sp² -sp³ Disilenes

Area of Science:

• Organosilicon Chemistry
• Inorganic Chemistry

Background:

• Disilenes, silicon analogs of alkenes, are typically characterized by two-coordinate silicon atoms.
• The synthesis of disilenes featuring differently coordinated silicon atoms has remained an elusive goal in chemistry.

Purpose of the Study:

• To synthesize and characterize novel disilenes with differentially coordinated silicon atoms.
• To explore the reactivity of a hypersilyl silylene with chlorophosphines.

Main Methods:

• Reaction of hypersilyl silylene PhC(NtBu)2SiSi(SiMe3)3 with aliphatic chlorophosphines.
• Characterization of synthesized compounds using spectroscopic and analytical techniques.
• Density Functional Theory (DFT) calculations to investigate bonding and reactivity.

Main Results:

• High-yield synthesis of novel disilenes with one three-coordinate and one four-coordinate silicon atom.
• The reaction with aliphatic chlorophosphines yielded a series of these unique disilenes.
• The reaction with diphenylphosphinous chloride unexpectedly produced the first tetraphosphinosilane.

Conclusions:

• The study reports the first synthesis of disilenes with differently coordinated silicon atoms.
• This work expands the scope of known disilene structures and their synthetic accessibility.
• DFT calculations provide insights into the electronic structure and reactivity patterns of these novel silicon compounds.