Tetramethylethylenediamine
| Tetramethylethylenediamine | |
|---|---|
 | |
 | |
| Other names N,N,N′,N′-Tetramethylethane-1,2-diamine[2] | |
| Identifiers | |
| CAS number | 110-18-9  |
| PubChem | 8037 |
| ChemSpider | 7746  |
| EC number | 203-744-6 |
| UN number | 2372 |
| MeSH | ',N'-tetramethylethylenediamine N,N,N',N'-tetramethylethylenediamine |
| ChEBI | CHEBI:32850 |
| RTECS number | KV7175000 |
| Beilstein Reference | 1732991 |
| Gmelin Reference | 2707 |
| Jmol-3D images | Image 1 |
| |
| |
| Properties | |
| Molecular formula | C6H16N2 |
| Molar mass | 116.20 g mol−1 |
| Appearance | Colorless liquid |
| Odor | Ichtyal, ammoniacal |
| Density | 0.7765 g mL−1 (at 20 °C) |
| Melting point | −58.6 °C; −73.6 °F; 214.5 K |
| Boiling point | 121.1 °C; 249.9 °F; 394.2 K |
| Solubility in water | Miscible |
| Acidity (pKa) | 8.97 |
| Basicity (pKb) | 5.85 |
| Refractive index (nD) | 1.4179 |
| Structure | |
| Hybridisation | sp3 at C2, N5, C6, C10, C13, N16, C17, C21 |
| Dipole moment | 0 D |
| Hazards | |
| MSDS | External MSDS |
| GHS pictograms |    |
| GHS signal word | DANGER |
| GHS hazard statements | H225, H302, H314, H332 |
| GHS precautionary statements | P210, P280, P305+351+338, P310 |
| EU Index | 612-103-00-3 |
| EU classification |  F  C |
| R-phrases | R11, R20/22, R34 |
| S-phrases | (S1/2), S16, S26, S36/37/39, S45 |
| NFPA 704 |
 4
2
1
|
| Flash point | 20 °C; 68 °F; 293 K |
| Explosive limits | 0.98–9.08% |
| LD50 |
|
| Related compounds | |
| Related amines | Triethylenetetramine |
| Related compounds | |
| Supplementary data page | |
| Structure and properties |
n, εr, etc. |
| Thermodynamic data |
Phase behaviour Solid, liquid, gas |
| Spectral data | UV, IR, NMR, MS |
| (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 | |
Tetramethylethylenediamine (TMEDA or TEMED) is a chemical compound with the formula (CH3)2NCH2CH2N(CH3)2. This species is derived from ethylenediamine by replacement of the four N-H groups with four N-methyl groups. It is a colourless liquid, although old samples often appear yellow. Its odor is remarkably similar to that of fish.[4]
As a reagent in organic and inorganic synthesis
TMEDA is widely employed as a ligand for metal ions. It forms stable complexes with many metal halides, e.g. zinc chloride and copper(I) iodide, giving complexes that are soluble in organic solvents. In such complexes, TMEDA serves as a bidentate ligand.
TMEDA has an affinity for lithium ions.[4] It converts n-butyllithium into a cluster of higher reactivity than the hexamer. BuLi/TMEDA is able to metallate or even doubly metallate many substrates including benzene, furan, thiophene, N-alkylpyrroles, and ferrocene.[4] Many anionic organometallic complexes have been isolated as their [Li(tmeda)2]+ complexes.[5] In such complexes [Li(tmeda)2]+ behaves like a quaternary ammonium salt, such as [NEt4]+.
Tmeda adduct of lithium bis(trimethylsilyl)amide. Notice that the diamine is a bidentate ligand.[1]
Other uses
Tetramethylethylenediamine is used with ammonium persulfate to catalyze the polymerization of acrylamide when making polyacrylamide gels, used in gel electrophoresis, for the separation of proteins or nucleic acids. Although the amounts used in this technique may vary from method to method, 0.1-0.2% v/v TMEDA is a "traditional" range. TMEDA can also be a component of Hypergolic propellants.
References
- ↑ K. W. Henderson, A. E. Dorigo, Qi-Long Liu, P. G. Williard "Effect of Polydentate Donor Molecules on Lithium Hexamethyldisilazide Aggregation: An X-ray Crystallographic and a Combination Semiempirical PM3/Single Point ab Initio Theoretical Study" J. Am. Chem. Soc. 1997, volume 119, pp. 11855. doi:10.1021/ja971920t
- ↑ "N,N,N',N'-tetramethylethylenediamine - Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. 16 September 2004. Retrieved 30 June 2012.
- ↑ "MSDS" (pdf).
- ↑ 4.0 4.1 4.2 Haynes, R. K.; Vonwiller, S. C.; Luderer, M. R. (2006). "N,N,N',N'-Tetramethylethylenediamine". In Paquette, L. Encyclopedia of Reagents for Organic Synthesis. New York: J. Wiley & Sons. doi:10.1002/047084289X.rt064.pub2.
- ↑ Morse, P. M.; Girolami, G. S. (1989). "Are d0 ML6 Complexes Always Octahedral? The X-ray Structure of Trigonal Prismatic [Li(tmed)]2[ZrMe6]". Journal of the American Chemical Society 111 (11): 4114–4116. doi:10.1021/ja00193a061.