Diamine

A diamine is a type of polyamine with exactly two amino groups. Diamines are mainly used as monomers to prepare polyamides, polyimides and polyureas. In terms of quantities produced, 1,6-diaminohexane, a precursor to Nylon 6-6, is most important, followed by ethylenediamine.^[1] Hydrazine (H₂NNH₂) is usually not considered a diamine since it is neither an amine nor is it dibasic.

1 Aliphatic diamines
2 Aromatic diamines
3 References
4 External links

Aliphatic diamines

Linear aliphatic diamines

2 carbons: ethylenediamine (1,2-diaminoethane). Related derivatives include the N-alkylated compounds ethambutol and TMEDA.
3 carbons: 1,3-diaminopropane (propane-1,3-diamine)
4 carbons: putrescine (butane-1,4-diamine)
5 carbons: cadaverine (pentane-1,5-diamine)
6 carbons: hexamethylenediamine (hexane-1,6-diamine)

Branched aliphatic diamines

Derivatives of ethylenediamine are numerous:

Xylylenediamines

Xylylenediamines are classified as alkylamines since the amine is not directly attached to an aromatic ring.

o-xylylenediamine or OXD
m-xylylenediamine or MXD
p-xylylenediamine or PXD

Aromatic diamines

Three phenylenediamines are known:^[2]

o-phenylenediamine or OPD
m-phenylenediamine or MPD
p-phenylenediamine or PPD. 2,5-Diaminotoluene is related to PPD but contains a methyl group on the ring.

Various N-methylated derivatives of the phenylenediamines are known:

dimethyl-4-phenylenediamine, a reagent.
N,N'-di-2-butyl-1,4-phenylenediamine, an antioxidant.

Examples with two aromatic rings include derivatives of biphenyl and naphthalene:

References

^ Karsten Eller, Erhard Henkes, Roland Rossbacher, Hartmut Höke "Amines, Aliphatic" in Ullmann's Encyclopedia of Industrial Chemistry, 2005 Wiley-VCH Verlag, Weinheim. doi:10.1002/14356007.a02_001
^ Robert A. Smiley “Phenylene- and Toluenediamines” in Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim. doi:10.1002/14356007.a19_405