It is typically very difficult to do a substitution reaction on an aromatic ring when the leaving group is flanked by two other bulky substituents. Moreover, in Section 22.3, we found that nucleophilic aromatic substitution requires strongly electron-withdrawing groups on the benzene ring. However, Pd-catalyzed coupling allows entry into such products. As examples, write the products of the following reactions and state which coupling reaction is being utilized. Ph n-BugSn Pd(0), PPhg ÓTf excess Pd(PPH3)4, Cul, NE13

It is typically very difficult to do a substitution reaction on an aromatic ring when the leaving group is flanked by two other bulky substituents. Moreover, in Section 22.3, we found that nucleophilic aromatic substitution requires strongly electron-withdrawing groups on the benzene ring. However, Pd-catalyzed coupling allows entry into such products. As examples, write the products of the following reactions and state which coupling reaction is being utilized. Ph n-BugSn Pd(0), PPhg ÓTf excess Pd(PPH3)4, Cul, NE13

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

Chapter24: Catalytic Carbon-carbon Bond Formation

Section: Chapter Questions

Problem 24.25P: It is typically very difficult to do a substitution reaction on an aromatic ring when the leaving...

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