Potassium bis(trimethylsilyl)amide (commonly abbreviated as KHMDS, Potassium(K) HexaMethylDiSilazide) or potassium hexamethyldisilazane is the chemical compound with the formula ((CH
3)
3Si)
2NK. It is a strong, non-nucleophilic base with an approximate pK
a of 26 (compare to
lithium diisopropylamide
Lithium diisopropylamide (commonly abbreviated LDA) is a chemical compound with the molecular formula . It is used as a strong base and has been widely utilized due to its good solubility in non-polar organic solvents and non-nucleophilic nature ...
, 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 pair
In chemistry, ion association is a chemical reaction whereby ions of opposite electric charge come together in solution to form a distinct chemical entity. Ion associates are classified, according to the number of ions that associate with each o ...
ing.
[{{cite journal , doi = 10.1021/ic00333a029 , journal = Inorg. Chem. , title = Ion pairing in is(trimethylsilyl)amidootassium: The x-ray crystal structure of unsolvated N(SiMe3)2 , year = 1990 , last1 = Tesh , first1 = Kris F. , last2 = Hanusa , first2 = Timothy P. , last3 = Huffman , first3 = John C. , volume = 29 , issue = 8 , pages = 1584–1586]
See also
*
Metal bis(trimethylsilyl)amides
Metal bis(trimethylsilyl)amides (often abbreviated as metal silylamides) are coordination complexes composed of a cationic metal with anionic bis(trimethylsilyl)amide ligands and are part of a broader category of metal amides.
Due to the bulky hy ...
References
Bis(trimethylsilyl)amides
Potassium compounds
Non-nucleophilic bases