Tetraethylammonium
Encyclopedia
Tetraethylammonium is a quaternary ammonium cation
consisting of four ethyl group
s attached to a central nitrogen
atom. Like other members of its class, it can be used to alter a compound's solubility by displacing hard acids
with this comparatively softer acid. For example, addition of tetraethylammonium bromide
to an aqueous solution of a sodium salt may cause it to precipitate from water as the tetraethylammonium salt. The tetraethylammonium salt may also be more lipophilic
, dissolving in organic solvents such as chloroform
.
An example of the tetraethylammonium cation is found in [NEt4]2[ReBr3(CO)3], a common precursor to rhenium compounds having the tricarbonyl fragment. It is synthesized from bromopentacarbonylrhenium(I)
by heating it with tetraethylammonium bromide in diglyme
.
-selective ion channel
blocker. It is used in neurophysiology
experiments to block the voltage activated potassium channel
s involved in the trailing part of the transmission of an action potential
along a neuron
. TEA is also known to reverse the action of drugs such as tubocurarine
, a non-depolarizing blocker. TEA evokes more release of the neurotransmitter, and thus it will reverse the competitive antagonistic
block of any drugs belonging to the curare
family.
TEA salts are used in supercapacitors as electrochemically active species.
Tetrodotoxin
(TTX) is another toxin used to elucidate the ionic currents involved in action potentials of neurons because it complements TEA by blocking relevant sodium channels.
Quaternary ammonium cation
Quaternary ammonium cations, also known as quats, are positively charged polyatomic ions of the structure NR4+, R being an alkyl group or an aryl group. Unlike the ammonium ion and the primary, secondary, or tertiary ammonium cations, the quaternary ammonium cations are permanently charged,...
consisting of four ethyl group
Ethyl group
In chemistry, an ethyl group is an alkyl substituent derived from ethane . It has the formula -C2H5 and is very often abbreviated -Et.Ethylation is the formation of a compound by introduction of the ethyl functional group, C2H5....
s attached to a central nitrogen
Nitrogen
Nitrogen is a chemical element that has the symbol N, atomic number of 7 and atomic mass 14.00674 u. Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.08% by volume of Earth's atmosphere...
atom. Like other members of its class, it can be used to alter a compound's solubility by displacing hard acids
HSAB theory
The HSAB concept is an acronym for 'hard and soft acids and bases. Also known as the Pearson acid base concept, HSAB is widely used in chemistry for explaining stability of compounds, reaction mechanisms and pathways....
with this comparatively softer acid. For example, addition of tetraethylammonium bromide
Tetraethylammonium bromide
Tetraethylammonium bromide is a quaternary ammonium salt. It is a common source for the tetraethylammonium cation. Currently, no NFPA 704 for TEABr has been established. Industrially, it can be used to determine the epoxide value of various adhesives....
to an aqueous solution of a sodium salt may cause it to precipitate from water as the tetraethylammonium salt. The tetraethylammonium salt may also be more lipophilic
Lipophilic
Lipophilicity, , refers to the ability of a chemical compound to dissolve in fats, oils, lipids, and non-polar solvents such as hexane or toluene. These non-polar solvents are themselves lipophilic — the axiom that like dissolves like generally holds true...
, dissolving in organic solvents such as chloroform
Chloroform
Chloroform is an organic compound with formula CHCl3. It is one of the four chloromethanes. The colorless, sweet-smelling, dense liquid is a trihalomethane, and is considered somewhat hazardous...
.
An example of the tetraethylammonium cation is found in [NEt4]2[ReBr3(CO)3], a common precursor to rhenium compounds having the tricarbonyl fragment. It is synthesized from bromopentacarbonylrhenium(I)
Bromopentacarbonylrhenium(I)
Bromopentacarbonylrhenium is an inorganic compound of rhenium, commonly used for the syntheses of other rhenium complexes.-Preparation:Bromopentacarbonylrhenium is commercially available...
by heating it with tetraethylammonium bromide in diglyme
Diglyme
Diglyme, or bis ether, is a solvent with a high boiling point. It is an organic compound which is the dimethyl ether of diethylene glycol. It is a clear, colorless liquid with a slight ether-like odor...
.
Biology
In biology, the tetraethylammonium cation is a potassiumPotassium
Potassium is the chemical element with the symbol K and atomic number 19. Elemental potassium is a soft silvery-white alkali metal that oxidizes rapidly in air and is very reactive with water, generating sufficient heat to ignite the hydrogen emitted in the reaction.Potassium and sodium are...
-selective ion channel
Ion channel
Ion channels are pore-forming proteins that help establish and control the small voltage gradient across the plasma membrane of cells by allowing the flow of ions down their electrochemical gradient. They are present in the membranes that surround all biological cells...
blocker. It is used in neurophysiology
Neurophysiology
Neurophysiology is a part of physiology. Neurophysiology is the study of nervous system function...
experiments to block the voltage activated potassium channel
Potassium channel
In the field of cell biology, potassium channels are the most widely distributed type of ion channel and are found in virtually all living organisms. They form potassium-selective pores that span cell membranes...
s involved in the trailing part of the transmission of an action potential
Action potential
In physiology, an action potential is a short-lasting event in which the electrical membrane potential of a cell rapidly rises and falls, following a consistent trajectory. Action potentials occur in several types of animal cells, called excitable cells, which include neurons, muscle cells, and...
along a neuron
Neuron
A neuron is an electrically excitable cell that processes and transmits information by electrical and chemical signaling. Chemical signaling occurs via synapses, specialized connections with other cells. Neurons connect to each other to form networks. Neurons are the core components of the nervous...
. TEA is also known to reverse the action of drugs such as tubocurarine
Tubocurarine
Tubocurarine is a neuromuscular-blocking drug or skeletal muscle relaxant in the category of non-depolarizing neuromuscular-blocking drugs, used adjunctively in anesthesia to provide skeletal muscle relaxation during surgery or mechanical ventilation...
, a non-depolarizing blocker. TEA evokes more release of the neurotransmitter, and thus it will reverse the competitive antagonistic
Receptor antagonist
A receptor antagonist is a type of receptor ligand or drug that does not provoke a biological response itself upon binding to a receptor, but blocks or dampens agonist-mediated responses...
block of any drugs belonging to the curare
Curare
Curare is a common name for various arrow poisons originating from South America. The three main types of curare are:* tubocurare...
family.
TEA salts are used in supercapacitors as electrochemically active species.
Tetrodotoxin
Tetrodotoxin
Tetrodotoxin, also known as "tetrodox" and frequently abbreviated as TTX, sometimes colloquially referred to as "zombie powder" by those who practice Vodou, is a potent neurotoxin with no known antidote. There have been successful tests of a possible antidote in mice, but further tests must be...
(TTX) is another toxin used to elucidate the ionic currents involved in action potentials of neurons because it complements TEA by blocking relevant sodium channels.