22.7 Cope Elimination

Course Menu
Chad's Organic Chemistry Master Course

Quizzes, Study Guides, Chapter Tests, Final Exam Reviews, Practice Final Exams, and More!

youtube-video-thumbnail

Cope Elimination

The Cope Elimination is an elimination reaction specifically for tertiary amines for which the major organic product is an alkene.  The leaving group involved (a hydroxyl amine) is a moderate base and therefore is not a good leaving group.  As a result, the major product is the Hofmann product (a.k.a. anti-Zaitsev product--the least substituted alkene).  An explanation for why a poor leaving group results in the Hofmann product can be found here:  7.7b Exceptions to Zaitsev’s Rule for E2 Reactions.

Cope Elimination

Cope Elimination Mechanism

The Cope Elimination occurs over the course of two steps:

  • Step 1 - Oxidation -- The oxidation of a tertiary amine to an amine oxide using hydrogen peroxide.
  • Step 2 Elimination - The amine oxide produced in step 1 undergoes E2 elimination.  This step is unique in that the oxide portion of the leaving group serves as the base involved in the elimination reaction.
Cope Elimination Mechanism