Diamines
A diamine is an organic compound with two amino groups. Diamines are 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.Vicinal diamines (1,2-diamines) are a structural motif in many biological compounds and are used as ligands in coordination chemistry.
Derivatives of ethylenediamine are prominent:
Xylylenediamines are classified as alkylamines since the amine is not directly attached to an aromatic ring.
Three phenylenediamines are known:
Various N-methylated derivatives of the phenylenediamines are known:
Examples with two aromatic rings include derivatives of biphenyl and naphthalene:
PPD (para-phenylenediamine)
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