In SN2 reactions of haloalkanes, the order of reactivity is RI>RBr>RCl>RF. Alkyl iodides are considerably more reactive than alkyl fluorides, often by factors as great as 106. All 1-halo-2,4-dinitrobenzenes, however, react at approximately the same rate in nucleophilic aromatic substitutions. Account for this difference in relative reactivities.

In SN2 reactions of haloalkanes, the order of reactivity is RI>RBr>RCl>RF. Alkyl iodides are considerably more reactive than alkyl fluorides, often by factors as great as 106. All 1-halo-2,4-dinitrobenzenes, however, react at approximately the same rate in nucleophilic aromatic substitutions. Account for this difference in relative reactivities.

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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