Tris(trimethylsilyl)silane

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Tris(trimethylsilyl)silane
Names
Preferred IUPAC name
1,1,1,3,3,3-Hexamethyl-2-(trimethylsilyl)trisilane
Other names
TTMS, supersilane
Identifiers
3D model (
JSmol
)
ChemSpider
ECHA InfoCard
100.203.666 Edit this at Wikidata
UNII
  • InChI=1S/C9H27Si4/c1-11(2,3)10(12(4,5)6)13(7,8)9/h1-9H3
    Key: SCHZCUMIENIQMY-UHFFFAOYSA-N
  • C[Si](C)(C)[Si]([Si](C)(C)C)[Si](C)(C)C
Properties
C9H28Si4
Molar mass 248.663 g·mol−1
Appearance colorless liquid
Density 0.806 g/cm3
Boiling point 82–84 °C (180–183 °F; 355–357 K) 12 Torr
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Tris(trimethylsilyl)silane is the

bond dissociation energy estimated at 84 kcal/mol. For comparison, the Si-H bond in trimethylsilane is 94 kcal/mol. With such a weak bond, the compound is used as a reagent to deliver hydrogen atoms. The compound has been described as an environmentally benign analogue of tributyltin hydride.[1][2]

Reactions

The compound can be prepared by protonation of tris(trimethylsilyl)silyl lithium, which is derived from tetrakis(trimethylsilyl)silane:[2]

(Me3Si)4Si + MeLi → (Me3Si)3SiLi + Me4Si
(Me3Si)3SiLi + HCl → (Me3Si)3SiH + LiCl

Alternatively, the reaction of trimethylsilyl chloride and trichlorosilane in the presence of lithium delivers the silane directly but in modest yield:[3]

3 Me3SiCl + HSiCl3 + 6 Li → (Me3Si)3SiH + 6 LiCl

Many coordination complexes have been prepared with (Me3Si)3Si (hypersilyl) ligand.[4] Chalcogenide derivatives of (Me3Si)3SiLi are also well developed:[5]

3 Me3SiLi + E → (Me3Si)3SiELi (E = S, Se, Te)

References