Lithium tetramethylpiperidide
| Lithium tetramethylpiperidide | |
|---|---|
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| IUPAC name Lithium tetramethylpiperidide | |
| Systematic name 1-Lithio-2,2,6,6-tetramethylpiperidine | |
| Identifiers | |
| CAS number | 38227-87-1  |
| PubChem | 11051814 |
| ChemSpider | 21428984 |
| Jmol-3D images | {{#if:[Li]N1C(C)(C)CCCC1(C)CCC1(C)CCCC(C)(C)N1[Li]|Image 1 Image 2 |
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| Properties | |
| Molecular formula | C9H18LiN |
| Molar mass | 147.19 g mol−1 |
| Acidity (pKa) | 37 |
(verify) (what is: / ?)Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa) | |
| Infobox references | |
Lithium tetramethylpiperidide (often abbreviated LiTMP or LTMP) is an chemical compound with the molecular formula C9H18LiN. It is used as a non-nucleophilic base, being comparable to LiHMDS in terms of pKa and steric hindrance.
Synthesis
It is synthesised by the deprotonation of 2,2,6,6-tetramethylpiperidine with n-butyllithium at -78 °C. Recent reports show that this reaction can also be performed 0 °C.[1] The compound is stable in a THF/ethylbenzene solvent mixture and commercially available as such.
Structure
Like many lithium reagents it has a tendency to aggregate, forming a tetramer in the solid state.[2]
See also
References
- ↑ amide primer H. J. Reich 2002
- ↑ M.F. Lappert, M.J. Slade, A. Singh, J.L. Atwood, R.D. Rogers and R. Shakir (1983). "Structure and reactivity of sterically hindered lithium amides and their diethyl etherates: crystal and molecular structures of [Li{N(SiMe3)2}(OEt2)]2 and tetrakis(2,2,6,6-tetramethylpiperidinatolithium)". Journal of the American Chemical Society 105 (2): 302–304. doi:10.1021/ja00340a031.