Tmeda

Tetramethylethylenediamine

Names
Other names N,N,N′,N′-Tetramethylethane-1,2-diamine
Identifiers
CAS Number	110-18-9 Y
3D model (Jmol)	Interactive image
Abbreviations	TMEDA, TEMED
Beilstein Reference	1732991
ChEBI	CHEBI:32850 N
ChemSpider	7746 N
ECHA InfoCard	100.003.405
EC Number	203-744-6
Gmelin Reference	2707
MeSH	N,N,N',N'-tetramethylethylenediamine
PubChem	8037
RTECS number	KV7175000
UN number	2372
InChI InChI=1S/C6H16N2/c1-7(2)5-6-8(3)4/h5-6H2,1-4H3 N Key: KWYHDKDOAIKMQN-UHFFFAOYSA-N N
SMILES CN(C)CCN(C)C
Properties
Chemical formula	C6H16N2
Molar mass	116.21 g·mol−1
Appearance	Colorless liquid
Odor	Fishy, 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
Hazards
Safety data sheet	See: data page
GHS pictograms
GHS signal word	DANGER
GHS hazard statements	H225, H302, H314, H332
GHS precautionary statements	P210, P280, P305+351+338, P310
EU classification (DSD)	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%
Lethal dose or concentration (LD, LC):
LD50 (median dose)	5.39 g kg−1(dermal, rabbit) 268 mg kg−1(oral, rat)
Related compounds
Related amines	Triethylenetetramine
Related compounds	Tetraacetylethylenediamine Ethylenediaminetetraacetic acid Ethambutol
Supplementary data page
Structure and properties	Refractive index (n), Dielectric constant (εr), etc.
Thermodynamic data	Phase behaviour solid–liquid–gas
Spectral data	UV, IR, NMR, MS
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
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 amine hydrogens with four methyl groups. It is a colorless liquid, although old samples often appear yellow. Its odor is remarkably similar to that of rotting fish.

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. When mixed with n-butyllithium, TMEDA's nitrogen atoms coordinate to the lithium, forming a cluster of higher reactivity than the tetramer or hexamer that n-butyllithium normally adopts. BuLi/TMEDA is able to metallate or even doubly metallate many substrates including benzene, furan, thiophene, N-alkylpyrroles, and ferrocene. Many anionic organometallic complexes have been isolated as their [Li(tmeda)₂]⁺ complexes. In such complexes [Li(tmeda)₂]⁺ behaves like a quaternary ammonium salt, such as [NEt₄]⁺.

It is also worth noting that s-BuLi/TMEDA is also a useful combination in organic synthesis. Utilization of this is useful in cases where the n-butyl anion is able to add into the starting material due to its weak nucleophilic nature. TMEDA is still capable of forming a metal complex with Li in this case as mentioned above.

TMEDA 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.