Tris(trimethylsilyl)silane, also called hypersilane, is the organosilicon compound with the formula (Me3Si)3SiH (where Me = CH3). It is a colorless liquid, and a hydrosilane: a compound with an Si-H bond.
Preparation Hypersilane can be prepared by protonation of tris(trimethylsilyl)silyl lithium, which is derived from tetrakis(trimethylsilyl)silane: (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 only modest yield: 3 Me3SiCl + HSiCl3 + 6 Li → (Me3Si)3SiH + 6 LiCl
Reactions The compound's Si−H bond is notably weak, with a bond dissociation energy estimated at 79–84 kcal/mol. For comparison, the Si−H bond in trimethylsilane requires 95 kcal/mol to dissociate, and the Sn−H bond in tributyltin hydride requires 74 kcal/mol. Indeed, the compound has been described as an environmentally benign analogue of tributyltin hydride. With such a weak bond, the compound is used as a reagent for hydrogen atom transfer.Recent Applications of the (TMS)3SiH Radical-Based Reagent, Chryssostomos Chatgilialoglu, Jacques Lalevée Molecules 2012, 17, 527-555;
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