1,3,5-Hexatriene refers to a pair of organic compounds with the formula . The compound is normally obtained as a mixture of cis- and trans-isomers.
Preparation It can be prepared by several methods, an optimized procedure involves dehydration of 1,5-hexadiene-3-ol, which is obtained from allyl Grignard reagent and acrolein.
The compound has been off interest theoretically, e.g. the Woodward-Hoffmann Rules. 1,3-cyclohexadiene undergoes photoinduced conrotatory ring-opening to give 1,3,5-hexatriene.
Reactions Protonation of 1,3,5-hexatriene gives the transient methylpentadienyl cation. It undergoes nitration, reminiscent of the behavior of benzene. With maleic anhydride, it undergoes Diels-Alder reaction.
Related compounds Diphenylhexatriene 1,3,5,7-Octatetraene, a colorless solid, can be prepared by a related procedure involving pentadienal in place of acrolein.
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