Haobo Ren

Publication Date

1990

Document Type

Dissertation/Thesis

First Advisor

Kevill, Dennis N.

Degree Name

M.S. (Master of Science)

Legacy Department

Department of Chemistry

LCSH

Benzyl; Nucleophilic reactions; Solvolysis

Abstract

The solvolyses in eleven solvents of benzyl and p- methyl, p-chloro, p-bromo, p-trifluoromethyl, p-nitro and m-fluorobenzyl tosylate have been studied. Using the extended Grunwald-Winstein equation, we found that the susceptibility to nucleophilic attack of benzyl tosylate is comparable to that of the secondary isopropyl tosylate. The l and m values for solvolyses of benzyl tosylate at 50.0°C, using N[sub OTs] and Y[sub 0Ts] values, are perfectly consistent with the values obtained by calculation using the Schadt-Bentley equation. The l and m values for other compounds show that the p-nitro, p-trifluoromethyl and p-fluoro-benzyl tosylate are much more sensitive to nucleophilic attack. The l and m values of p-chloro and p-bromobenzyl tosylate solvolysis are close to those for the unsubstituted benzyl tosylate solvolysis. The solvolyses of p-methylbenzyl tosylate are very sensitive to the ionization power of the solvents, and the p-methylbenzyl tosylate solvolysis can be considered as an S[sub N]1 reaction but with a fairly strong nucleophilic solvation of the developing carbocation. From the Hammett plot of the solvolyses of benzyl and substituted benzyl tosylates in 95% acetone at 50.0°C, we see that the p-methylbenzyltosylate is far above the line of the other compounds. It implies that the p- methylbenzyltosylate solvolyzes via a different mechanism (S[sub N]1) from the other compounds (S[sub N]2).

Comments

Includes bibliographical references (pages 67-72)

Extent

ix, 72 pages

Language

eng

Publisher

Northern Illinois University

Rights Statement

In Copyright

Rights Statement 2

NIU theses are protected by copyright. They may be viewed from Huskie Commons for any purpose, but reproduction or distribution in any format is prohibited without the written permission of the authors.

Media Type

Text

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