Lithium bis(trimethylsilyl)amide
Lithium bis(trimethylsilyl)amide is a lithiated organosilicon compound. Its chemical formula is LiN(SiMe3)2. It is commonly abbreviated as LiHMDS which means lithium hexamethyldisilazide. It is mainly used as a strong non-nucleophilic base and as a ligand.
Preparation
It can be made by the deprotonation of bis(trimethylsilyl)amine with n-butyllithium.[1] Once its made, the compound can be purified by sublimation or distillation.
Uses
It is often used in organic chemistry as a strong non-nucleophilic base.[2] It can be used to make many organolithium compounds, including acetylides or lithium enolates.[2][3]
Lithium Bis(trimethylsilyl)amide Media
In situ formation then reaction of w:LiHMDS with w:Benzylideneacetone to produce an enolate. See Danheiser, R. L.; Miller, R. F.; Brisbois, R. G. (1990), "Detrifluoroacetylative Diazo Group Transfer: (E)-1-Diazo-4-phenyl-3-buten-2-one", Org. Synth. 73: 134,
The aggregation of lithium bis(trimethylsilyl)amide (LiHMDS) into dimers, trimers and higher oligomers
structure of LiHMDS-tmeda complex
crystallographically determined structure of Li2[N(Sitms2])2(THF)2
crystallographically determined structure of "Li[N(Sitms2])2"
2(THF)2.png)
2%22.png)
References
- ↑ Amonoo-Neizer, E. H.; Shaw, R. A.; Skovlin, D. O.; Smith, B. C.; Rosenthal, Joel W.; Jolly, William L. (2007-01-05). Holtzlaw, Henry F. (ed.). Inorganic Syntheses. Hoboken, NJ, USA: John Wiley & Sons, Inc. pp. 19–22. doi:10.1002/9780470132395.ch6. ISBN 978-0-470-13239-5.[dead link]
- ↑ 2.0 2.1 Wu, George; Huang, Mingsheng (2006). "Organolithium Reagents in Pharmaceutical Asymmetric Processes". Chemical Reviews. 106 (7): 2596–2616. doi:10.1021/cr040694k. ISSN 0009-2665. PMID 16836294.
- ↑ Wu, George; Huang, Mingsheng (2006). "Organolithium Reagents in Pharmaceutical Asymmetric Processes". Chemical Reviews. 106 (7): 2596–2616. doi:10.1021/cr040694k. ISSN 0009-2665. PMID 16836294.
