Problems and exercisesPericyclic Reactions
1. Cis or trans?
Which stereoisomer of 5,6-dimethyl-1,3-cyclohexadiene is obtained thermally from (2E,4Z,6Z)-2,4,6-octatriene?
2. Cyclobutenes
cis-3,4-Dimethylcyclobutene opens on heating. Which isomer of 2,4-hexadiene is obtained?
3. The rules
Complete: an 8-electron electrocyclic reaction is ______ thermally and ______ photochemically.