Editing Imidazole (section)

===Formation of two bonds===
The (1,2) and (2,3) bonds can be formed by treating a 1,2-diamino[[alkane]], at high temperatures, with an [[Alcohol (chemistry)|alcohol]], [[aldehyde]], or [[carboxylic acid]]. A dehydrogenating catalyst, such as [[platinum]] on [[alumina]], is required.
:[[File:Imidazole_two-bond-method.svg|none|400px|Formation of two bonds]]
The (1,2) and (3,4) bonds can also be formed from ''N''-substituted α-aminoketones and [[formamide]] with heat. The product will be a 1,4-disubstituted imidazole, but here since R<sub>1</sub> = R<sub>2</sub> = hydrogen, imidazole itself is the product. The yield of this reaction is moderate, but it seems to be the most effective method of making the 1,4 substitution.
::[[File:(1,2)(3,4)_formation_imidazole.svg|none|400px|Formation of three bonds]]