Reaction and mechanism of p-nitrobenzyl halide with phosphite and phosphonate anions in dimethyl sulfoxide
Date
1998
Authors
Rhee, Jong Uk
Major Professor
Advisor
Espenson, James H.
Committee Member
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
It is well known that the phosphorus group is widely formed in natural compounds and there are enormous possibilities for structural variation of these compounds with potential biological activity. The purpose of this research was to investigate the reaction of p-02NC6H4C(R)(R')X (R = H or CH3, R'= H or CH3, X = Cl or Br) with a variety of dialkyl phosphite and phosphonate anions in dimethyl sulfoxide and to explain its reaction mechanism. Dialkyl phosphate and dialkyl phosphonate anions were generated in dimethyl sulfoxide solution by reaction with one equivalent of base with (RO)2P(O)H and N02C6H4CH2 [P(O)(OR)2].
The reactions were performed under three different conditions: (a) ordinary laboratory lighting at 250C; (b) with 10-15% of (t-BU)2NO· present; and (c) with a fluorescent sunlamp (275 W) irradiation at 35-40 0C. The reaction of p-nitrobenzyl chloride showed the inhibitory effect of (t-BU)2NO· and the reaction rate was accelerated by sunlamp irradiation, but p-nitrobenzyl bromide was not affected. These results suggest that the reaction of p-02NC6H4CH2Cl with dialkyl phosphate anions mainly goes through the S[Subfield RN]l mechanism while the reaction Of p-02NC6H4CH2Br goes through the S[Subscript N]2. The strategy described in this thesis may be applied for making potentially biologically active phosphonate compounds that cannot easily be synthesized by the S[Subscript N]2 process.
Series Number
Journal Issue
Is Version Of
Versions
Series
Academic or Administrative Unit
Type
thesis