When considering the photochemical cis-trans isomerization of trans-stilbene, an electrocyclization is observed. The product of this electrocyclization is usually oxidized to a condensed aromatic product (by oxygen or addition of other oxidizing reagents such as iodine). Discuss the mechanism of electrocyclic ring formation and ring opening non- verbally by showing orbital images, indicate the orientation of the cyclization / opening, and shoe how this reaction is crucial in the synthesis of helicenes.

When considering the photochemical cis-trans isomerization of trans-stilbene, an electrocyclization is observed. The product of this electrocyclization is usually oxidized to a condensed aromatic product (by oxygen or addition of other oxidizing reagents such as iodine). Discuss the mechanism of electrocyclic ring formation and ring opening non- verbally by showing orbital images, indicate the orientation of the cyclization / opening, and shoe how this reaction is crucial in the synthesis of helicenes.

Organic Chemistry

9th Edition

ISBN:9781305080485

Author:John E. McMurry

Publisher:John E. McMurry

Chapter16: Chemistry Of Benzene: Electrophilic Aromatic Substitution

Section16.SE: Something Extra

Problem 25VC: The following molecular model of a dimethyl-substituted biphenyl represents the lowest-energy...

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