Tris(2-aminoethyl)amine is the

organic compound In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The ...

with the

formula In science, a formula is a concise way of expressing information symbolically, as in a mathematical formula or a ''chemical formula''. The informal use of the term ''formula'' in science refers to the general construct of a relationship betwee ...

N(CH₂CH₂NH₂)₃. This colourless liquid is soluble in water and is highly basic, consisting of a

tertiary amine In chemistry, amines (, ) are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia (), wherein one or more hydrogen atoms have been replaced by a substituent such a ...

center and three pendant

primary amine In chemistry, amines (, ) are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia (), wherein one or more hydrogen atoms have been replaced by a substituent such a ...

groups. Abbreviated tren or TREN it is a crosslinking agent in the synthesis of polyimine networks and a tripodal ligand in

coordination chemistry A coordination complex consists of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many ...

. Tren is a C3-symmetric,

tetradentate In chemistry, tetradentate ligands are ligands that bind four donor atoms to a central atom to form a coordination complex. This number of donor atoms that bind is called denticity and is a method of classifying ligands. Tetradentate ligands ar ...

chelating

ligand In coordination chemistry, a ligand is an ion or molecule (functional group) that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's electr ...

that forms stable complexes with transition metals, especially those in the 2+ and 3+ oxidation states. Tren complexes exist with relatively few isomers, reflecting the constrained connectivity of this tetramine. Thus, only a single achiral stereoisomer exists for o(tren)X₂sup>+, where X is halide or pseudohalide. In contrast, for o(trien)X₂sup>+ five diastereomers are possible, four of which are chiral. In a few cases, tren serves as a

tridentate ligand A tridentate ligand (or terdentate ligand) is a ligand that has three atoms that can function as acceptor atoms in a coordination complex. Well-known tridentate ligands include diethylenetriamine with three nitrogen donor atoms, and the iminodia ...

with one of the primary amine groups non-coordinated. Tren is a common impurity in the more common

triethylenetetramine Triethylenetetramine (TETA and trien), also known as trientine (INN) when used medically, is an organic compound with the formula H2NHCH2CH2NH2sub>2. The pure freebase is a colorless oily liquid, but, like many amines, older samples assume a yell ...

("trien"). As a trifunctional amine, tren forms a tri

isocyanate In organic chemistry, isocyanate is the functional group with the formula . Organic compounds that contain an isocyanate group are referred to as isocyanates. An organic compound with two isocyanate groups is known as a diisocyanate. Diisocyan ...

when derivatized with COCl₂. It condenses with aldehydes to give imines.

N-methylated derivatives

The permethylated derivative of tren has the formula N(CH₂CH₂NMe₂)₃. "Me₆tren" forms a variety of complexes but, unlike tren, does not stabilize Co(III). Related amino-triphosphines are also well developed, such as N(CH₂CH₂PPh₂)₃ (m.p. 101-102 °C). This species is prepared from the nitrogen mustard N(CH₂CH₂Cl)₃. N,N,N-trimethyltren, N(CH₂CH₂NHMe)₃ is also available.

Safety considerations

(H₂NCH₂CH₂)₃N, like other polyamines, is corrosive. The Physical and Theoretical Chemistry Laboratory Oxford University MSDS
/ref> It causes severe skin burns and eye damage, is harmful if inhaled due to the destruction of respiratory tissues, is toxic if swallowed, and can be fatal in contact with skin. Its

median lethal dose In toxicology, the median lethal dose, LD50 (abbreviation for "lethal dose, 50%"), LC50 (lethal concentration, 50%) or LCt50 is a toxic unit that measures the lethal dose of a toxin, radiation, or pathogen. The value of LD50 for a substance is the ...

is 246 mg/kg, oral (rat), and 117 mg/kg, dermal (rabbit). It is also combustible.

References

{{reflist Ethyleneamines Tripodal ligands Tertiary amines