a) The following two cyclobutenes 4 and 5 can be opened to form diene structures thermally, however one reacts much slower than the other. Which of 4 or 5 reacts faster and which slower, and why? Use suitable diagrams to illustrate your answer. 4 5 b) HARD: Both 4 and 5 can also react photochemically to give one monocyclic product each, isomeric with the starting materials. Draw the structures of the products and rationalize their formation. (HINT: Electrocyclization reactions are NOT involved in the formation of the monocyclic products.)

a) The following two cyclobutenes 4 and 5 can be opened to form diene structures thermally, however one reacts much slower than the other. Which of 4 or 5 reacts faster and which slower, and why? Use suitable diagrams to illustrate your answer. 4 5 b) HARD: Both 4 and 5 can also react photochemically to give one monocyclic product each, isomeric with the starting materials. Draw the structures of the products and rationalize their formation. (HINT: Electrocyclization reactions are NOT involved in the formation of the monocyclic products.)

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter6: Reactions Of Alkenes

Section: Chapter Questions

Problem 6.27P: Reaction of this bicycloalkene with bromine in carbon tetrachloride gives a trans dibromide. In both...

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