During studies directed toward the synthesis of atropurpuran, a diterpene with interesting molecular architecture, the investigators used high temperature to convert an acyclic tetraene into a tricyclic compound, shown below. (Org. Lett. 2010, 12, 1152-1155). This transformation is believed to occur via two successive pericyclic processes (an electrocyclic ring-closing reaction, followed by a Diels- Alder cycloaddition). Draw the mechanism as described. R₂N. NTS 135°C R₂N NTS

During studies directed toward the synthesis of atropurpuran, a diterpene with interesting molecular architecture, the investigators used high temperature to convert an acyclic tetraene into a tricyclic compound, shown below. (Org. Lett. 2010, 12, 1152-1155). This transformation is believed to occur via two successive pericyclic processes (an electrocyclic ring-closing reaction, followed by a Diels- Alder cycloaddition). Draw the mechanism as described. R₂N. NTS 135°C R₂N NTS

Organic Chemistry

9th Edition

ISBN:9781305080485

Author:John E. McMurry

Publisher:John E. McMurry

Chapter22: Carbonyl Alpha-substitution Reactions

Section22.SE: Something Extra

Problem 33MP

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