Tetraethylammonium
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Preferred IUPAC name
N,N,N-Triethylethanaminium | |
Other names
Tetraethylazanium
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3D model (
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ChEMBL | |
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PubChem CID
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UNII | |
CompTox Dashboard (EPA)
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Properties | |
C8H20N+ | |
Molar mass | 130.25 g/mol |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Tetraethylammonium (TEA) is a
Preparation
The halide salt is prepared by the reaction of triethylamine and an ethyl halide:
This method works well for the preparation of tetraethylammonium iodide (where X = I).[1]
Most tetraethylammonium salts are prepared by
Other examples include tetraethylammonium cyanide (Et4NCN),[3] and trichlorostannate (Et4NSnCl3).[4] In some cases, salts are produced of anions that cannot be generated in water, such as the tetrahedral [NiCl4]2− salt.[5]
Uses
The principal chemical characteristic of tetraethylammonium salts is their ability to engage in processes involving phase-transfer, such as
TEA salts such as tetraethylammonium tetrafluoroborate and tetraethylammonium methylsulfonate are used in supercapacitors as organic electrolytes.[7]
TEA halide and its hydroxide are used for the synthesis of high-silica zeolite, especially for the zeolite beta.[8] TEA can act as a template for micropore of zeolites under hydrothermal conditions during crystallization processes.
Properties
The effective radius of the tetraethylammonium ion is reported as ~0.45 nm, which is comparable in size to that of the hydrated K+ ion.[9] The ionic radius for TEA is given as 0.385 nm; several thermodynamic parameters for the TEA ion are also recorded.[10][11]
The octanol-water partition coefficient of TEA iodide, Po-w was determined experimentally to be 6.9×10−4 (or log P ≈ −3.16).[12]
Biology
Pharmacology
The literature dealing with the pharmacologically-related properties of tetraethylammonium is vast, and research continues.
At the mechanistic level, TEA has long been known to block voltage-dependent K+ channels in nerve,
A partial effect of these voltage-dependent and permeability properties within each system mentioned above is not only due to the aforementioned inhibitory properties of TEA, but also its ability to inhibit Na,K-ATPase. Acting on the extracellular vestibule of the Na,K-ATPase, inhibiting K+ access similar to ouabain, TEA further accentuates the disrupted K, and Na, gradients within each of these systems.[25]
Clinical considerations
Although TEA (sometimes under the name "Etamon"
TEA is not orally active.[29] Typical symptoms produced in humans include the following: dry mouth, suppression of gastric secretion, drastic reduction of gastric motility, paralysis of urinary bladder, and relief of some forms of pain.[16] Most studies with TEA seem to have been performed using either its chloride or bromide salt without comment as to any distinctions in effect, but Birchall and his co-workers preferred the use of TEA chloride in order to avoid the sedative effects of the bromide ion.[30]
Toxicology
An extensive study of the toxicology of tetraethylammonium chloride in mice, rats and dogs was published by Gruhzit and co-workers in 1948. These workers reported the following symptoms in mice and rats receiving toxic parenteral doses: tremors, incoordination, flaccid prostration, and death from respiratory failure within 10–30 minutes; dogs exhibited similar symptoms, including incoordination, flaccid prostration, respiratory and cardiac depression, ptosis, mydriasis, erythema, and death from respiratory paralysis and circulatory collapse. After non-lethal doses, symptoms abated within 15–60 minutes. There was little evidence of toxicity from chronic administration of non-lethal doses.[31] These investigators recorded the following acute toxicities, as LD50s for TEA chloride (error ranges not shown):
- Mouse: 65 mg/kg, i.p.; 900 mg/kg, p.o.
- Rat: ~56 mg/kg, i.v.; 110 mg/kg, i.m.; 2630 mg/kg, p.o.
- Dog: ~36 mg/kg, i.v.; 58 mg/kg, i.m.
Another research group, working at about the same time, but using tetraethylammonium bromide, published the following LD50 data:[32]
- Mouse: 38 mg/kg, i.v.; 60 mg/kg, i.p.; >2000 mg/kg, p.o.
- Rat: 63 mg/kg, i.v.; 115 mg/kg, i.p.
- Dog: 55 mg/kg, i.v.
- Rabbit: 72 mg/kg, i.v.
Writing in 1950, Graham made some observations on the toxic effects of tetraethylammonium bromide in humans. In one subject, described as a "healthy woman", 300 mg of tetraethylammonium bromide, i.v., produced incapacitating "curariform" (i.e., resembling the effects of
See also
References
- ^ A. A. Vernon and J. L. Sheard (1948). "The solubility of tetraethylammonium iodide in benzene-ethylene dichloride mixtures." J. Am. Chem. Soc. 70 2035-2036. https://doi.org/10.1021/ja01186a015
- ^ I. M. Kolthoff and J. F. Coetzee (1957). "Polarography in acetonitrile. I. Metal ions which have comparable polarographic properties in acetonitrile and in water." J. Am. Chem. Soc. 79 870-874.
- ^ C. M. Starks, C. L. Liotta and M. Halpern (1994). "Phase-Transfer Catalysis: Fundamentals, Applications, and Industrial Perspectives." Springer.
- ^ J. Huang, B. G. Sumpter and V. Meunier (2008). "A universal model for nanoporous carbon supercapacitors applicable to diverse pore regimes, carbon materials, and electrolytes." Chem. Eur. J. 14 6614-6626
- ^ US patent 5139759A, "Synthesis of zeolite beta", issued 1992-08-18
- ^ a b C. M. Armstrong (1971). "Interaction of tetraethylammonium ion derivatives with the potassium channels of giant axons." J. Gen. Physiol. 58 413-437.
- ^ D. H. Aue, H. M. Webb and M. T. Bowers (1976). "A thermodynamic analysis of solvation effects on the basicities of alkylamines. An electrostatic analysis of substituent effects." J. Am. Chem. Soc. 98 318–329.
- ^ J. Palomo and P. N. Pintauro (2003). "Competitive absorption of quaternary ammonium and alkali metal cations into a Nafion cation-exchange membrane." J. Membrane Sci. 215 103-114.
- ^ H. Tsubaki, E. Nakajima, T. Komai and H. Shindo (1986). "The relation between structure and distribution of quaternary ammonium ions in mice and rats. Simple tetraalkylammonium and a series of m-substituted trimethylphenylammonium ions." J. Pharmacobio-Dyn. 9 737-746.
- ^ There are over 8500 citations in PubMed, as of October 2012.
- ^ Since tetraethylammonium is always paired with an anion, the TEA salts, TEA chloride, TEA bromide, or TEA iodide have actually been used, but not always specified as such. Here, the term "TEA" is written for convenience.
- ^ a b Drill's Pharmacology in Medicine, 4th Ed. (1971). J. R. DiPalma (Ed.), pp. 723-724, New York: McGraw-Hill.
- ^ a b c G. K. Moe and W. A. Freyburger (1950). "Ganglionic blocking agents." Pharmacol. Rev. 2 61-95.
- ^ R. C. Elliott (1982). "The action of tetraethylammonium at the neuromuscular junction." Gen. Pharmacol. 13 11-14.
- ^ a b V. Ceña, A. G. García, C. Gonzalez-Garcia, and S. M. Kirpekar (1985). "Ion dependence of the release of noradrenaline by tetraethylammonium and 4-aminopyridine from cat splenic slices." Br. J. Pharmacol. 84 299–308.
- ^ B. Hille (1967). "The selective inhibition of delayed potassium currents in nerve by tetraethylammonium ions." J. Gen. Physiol. 50 1287-1302.
- ^ G. Akk and J. H. Steinbach (2003). "Activation and block of mouse muscle-type nicotinic receptors by tetraethylammonium." J. Physiol. 551 155-168.
- ^ R. Latorre, C. Vergara, and C. Hidalgo (1982). "Reconstitution in planar lipid bilayers of a Ca2+-dependent K+ channel from transverse tubule membranes isolated from rabbit skeletal muscle." Proc. Natl. Acad. Sci. 79 805-809.
- ^ D. G. Lang and A. K. Ritchie (1990. "Tetraethylammonium blockade of apamin-sensitive and insensitive Ca2+-activated K+ channels in a pituitary cell line." J. Physiol. 425 117-132.
- ^ E. M. Müller, J. S. Hub, H. Grubmüller, and B. L. de Groot (2008). "Is TEA an inhibitor for human Aquaporin-1?" Pflügers Arch. 456 663–669, and references herein.
- ^ R. Søgaard and T. Zeuthen (2008). "Test of blockers of AQP1 water permeability by a high-resolution method: no effects of tetraethylammonium ions or acetazolamide." Pflügers Arch. 456 285-292
- ^ 1988. Inhibition of the electrogenic Na,K pump and Na,K-ATPase activity by tetraethylammonium, tetrabutylammonium, and apamin. Zemková H, Teisinger J, Vyskocil F. J Neurosci Res. Apr;19(4):497-503
- ^ J. P. Hendrix (1949. "Neostigmine as antidote to Etamon®." JAMA 139(11) 733-734.
- ^ S. W. Hoobler, G. K. Moe and R. H. Lyons (1949). "The cardiovascular effects of tetraethylammonium in animals and man with special reference to hypertension." Med. Clin. N. Amer. 33 805-832.
- ^ a b c A. J. P. Graham (1950). "Toxic effects in animals and man after tetraethylammonium bromide." Br. Med. J. 2 321-322.
- ^ A. M. Boyd et al. (1948). "Action of tetraethylammonium bromide." Lancet 251 15-18.
- ^ a b R. Birchall et al. (1947). "Clinical studies of the pharmacological effects of tetraethyl ammonium chloride in hypertensive persons made in an attempt to select patients suitable for lumbodorsal sympathectomy and ganglioectomy." Am. J. Med. Sci. 213 572-578
- ^ O. M. Gruhzit, R. A. Fisken and B. J. Cooper (1948). "Tetraethylammonium chloride [(C2H5)4NCl]. Acute and chronic toxicity in experimental animals." J. Pharmacol. Exp. Ther. 92 103-107.
- ^ L. O. Randall, W. G. Peterson and G. Lehmann (1949). "The ganglionic blocking actions of thiophanium derivatives." J. Pharmacol. Exp. Ther. 97 48-57.