Publication Date

1998

Document Type

Dissertation/Thesis

First Advisor

Kevill, Dennis N.

Degree Name

M.S. (Master of Science)

Department

Department of Chemistry and Biochemistry

LCSH

Organochlorine compounds--Mathematical models||Organophophorus compounds--Mathematical models||Solvolysis--Mathematical models

Abstract

The extended Grunwald-Winstein equation is applied to the solvolysis of dimethyl chlorothiophosphate [(CH[sub 3]O)[sub 2]PSCl] and dimethyl chlorophosphate [(CH[sub 3]O)[sub 2] POCl]. The kinetics of the solvolysis o f both compounds were determined in a variety of pure and binary solvent mixtures. In the Grunwald-Winstein equation k is the specific rate constant in a given solvent mixture and k[sub 0] is the rate constant in 80 % ethanol. Using established values for the solvent nucleophilicities (N[sub r]) and the solvent ionizing power with a chloride-ion leaving group (Y[sub Cl]), the multiple regression analysis of log(k/ko) versus 1N[sub r] + mY[sub Cl] + c gives values for m, the sensitivity to changes in the solvent ionizing power; for l, the sensitivity to changes in the solvent nucleophilicity; and for c. the constant (residual) term. There is reasonable linear relationship between the log(k/ko) and (lN[sub r] + mY[sub Cl]) for both compounds. A comparison with solvolyses of related compounds with phenyl or m-chlorophenyl groups within (RO)[sub 2]POCl is also made. The dimethyl chlorophosphate (1 = 1.27, m 0.47) appears to follow the same mechanism as was discussed in previous related studies by Miller and Abduljaber. The dimethyl chlorothiophosphate varies only a very little from that trend (1 = 1.17, m = 0.55) and unlike for the solvolyses of chloroformate esters, introduction of sulfur does not give any observable movement towards an ionization pathway.

Comments

Includes bibliographical references (pages [52]-55)

Extent

viii, 55 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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