A cyclooctadiene (often abbreviated COD) is any of several cyclic diene with the formula (CH2)4(C2H2)2. Focusing only on cis derivatives, four isomers are possible: 1,2-, which is an allene, 1,3-, 1,4-, and 1,5-. Commonly encountered isomers are the conjugated isomer 1,3-cyclooctadiene and 1,5-cyclooctadiene, which is used as a ligand for transition metals. These dienes are colorless volatile liquids.[1]
References
^Thomas Schiffer, Georg Oenbrink “Cyclododecatriene, Cyclooctadiene, and 4-Vinylcyclohexene” in Ullmann’s Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim.doi:10.1002/14356007.a08_205
