Potassium bis(trimethylsilyl)amide

Potassium bis(trimethylsilyl)amide
Identifiers
Abbreviations KHMDS
CAS number 40949-94-8 Y
PubChem 3251421
ChemSpider 21171158 N
UN number 3263
Jmol-3D images Image 1
Properties
Molecular formula KSi2C6NH18
Molar mass 199.4831 g mol-1
Exact mass 199.061484508 g mol-1
Appearance White, opaque crystals
Solubility in water Reacts
Hazards
GHS pictograms
GHS signal word DANGER
GHS hazard statements H314
GHS precautionary statements P280, P305+351+338, P310
EU classification C
R-phrases R14, R34
S-phrases S26, S36/37/39, S43, S45
Related compounds
Other cations Lithium bis(trimethylsilyl)amide

Sodium bis(trimethylsilyl)amide

 N (verify) (what is: Y/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Potassium bis(trimethylsilyl)amide (commonly abbreviated as KHMDS, Potassium(K) HexaMethylDiSilazide) is the chemical compound with the formula ((CH3)3Si)2NK. It is a strong, non-nucleophilic base with an approximate pKa of 26 (compare to lithium diisopropylamide, at 36).

Structure

In the solid state, the unsolvated compound is dimeric, with two potassium and two nitrogen atoms forming a square. This compound is soluble in hydrocarbon solvents, and conducts electricity poorly in solution and in the melt. This is attributed to very strong ion-pairing.[1]

See also

References

  1. ^ Tesh, Kris F.; Hanusa, Timothy P.; Huffman, John C. (1990). "Ion pairing in [bis(trimethylsilyl)amido]potassium: The x-ray crystal structure of unsolvated [KN(SiMe3)2]2". Inorg. Chem. 29 (8): 1584–1586. doi:10.1021/ic00333a029.