Q7(b)(i). 6π electrocyclic ring closure: thermal and photochemical modes
Following are examples of pericyclic reactions. Predict the pathway (thermal/photochemical) and the mode of rotation involved in each case. Also provide the HOMO involved, with correct phase relationships, in both pathways. [diphenyl hexatriene giving A and B; scheme given in the paper]
Answer in brief
Triene → B (cis): thermal, disrotatory, HOMO = ψ₃. Triene → A (trans): photochemical, conrotatory, HOMO = ψ₄.
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Coverselectrocyclic reactionWoodward-Hoffmann rulesconrotatorydisrotatoryHOMOhexatriene
All parts of Question 7
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