A hetero Diels-Alder reaction is a variation of the Diels-Alder reaction in which one or more of the carbon atoms of the diene and/or the dienophile are replaced by other atoms such as oxygen or nitrogen. With this in mind, propose a mechanism for the following transformation in which an acyclic reactant produces a macrocyclic (containing a large ring) product (Org. Lett. 2001, 3, 723-726). Include lone pairs and charges in your answer. Do not draw out any hydrogen explicitly in your products. Do not use abbreviations such as Me or Ph. 2 Ph Ph- 195°C -Ph Draw any remaining curved arrow(s) to complete the first step of the mechanism.

A hetero Diels-Alder reaction is a variation of the Diels-Alder reaction in which one or more of the carbon atoms of the diene and/or the dienophile are replaced by other atoms such as oxygen or nitrogen. With this in mind, propose a mechanism for the following transformation in which an acyclic reactant produces a macrocyclic (containing a large ring) product (Org. Lett. 2001, 3, 723-726). Include lone pairs and charges in your answer. Do not draw out any hydrogen explicitly in your products. Do not use abbreviations such as Me or Ph. 2 Ph Ph- 195°C -Ph Draw any remaining curved arrow(s) to complete the first step of the mechanism.

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

Chapter20: Dienes, Conjugated Systems, And Pericyclic Reactions

Section: Chapter Questions

Problem 20.35P: The following triene undergoes an intramolecular Diels-Alder reaction to give a bicyclic product....

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