Triazole

Triazoles exhibit substantial isomerism, depending on the positioning of the nitrogen atoms within the ring.

Lastly, the many free lone pairs in triazoles make them useful as coordination compounds, although not typically as haptic ligands.

A common technique for unsubstituted triazoles is the Huisgen azide-alkyne 1,3-dipolar cycloaddition: a azide and an alkyne react at high temperature to form a ring.

One such catalyst is CuBr(PPh3)3, which is relatively stable towards oxidation even at elevated temperatures and can produce triazoles with a broad range of substituents either in solvent[1][2] or under neat[3] reaction conditions.

Cyclohexylethyltriazol was briefly used as an alternative to Cardiazol (Metrazol) in convulsive shock therapy treatment of mental illnesses during the 1940s.

Due to spreading resistance of plant pathogens towards fungicides of the strobilurin class,[10] control of fungi such as Septoria tritici or Gibberella zeae[11] relies heavily on triazoles.

-HN-N=N-CH=CH- interconverts with =N-HN-N=CH-CH= (1,2,3-triazole) and -HN-N=CH-N=CH- interconverts with =N-N=CH-NH-CH= (1,2,4-triazole)
Thermal addition gives a mixture of 1,4 and 1,5 isomers
Thermal addition gives a mixture of 1,4 and 1,5 isomers
1,4 isomer from a CuI catalyst
1,4 isomer from a Cu I catalyst
1,5 isomer from a Ru catalyst
1,5 isomer from a Ru catalyst