Date of Award
Union College Only
Bachelor of Science
Within the past fifteen years bimolecular nucleophilic substitution reactions at the sp3 hybridized nitrogen center have been the topic of some investigation. The synthesis of 0-substituted hydroxylamines was undertaken in order to obtain substrates for the study of these substitution reactions. Mesitylenesulfonyl chloride and t-butyl N-hydroxycarbamate were reacted to form the N-blocked t-butyl N-mesitylenesulfonyloxycarbamate. Subsequent acid cleavage of the nitrogen blocking group with trifluoroacetic acid yielded 0-mesitylenesulfonylhydroxylamine. Unsuccessful kinetic studies of the reaction of iodide with 0-mesitylenesulfonylhydroxylamine are reported. Attempts to synthesize 0-(2, 4-dinitrophenyl) hydroxylamine utilizing t-butyl N-hydroxycarbamate and ethyl acetohydroxamate as a sources of N-blocked hydroxylamine failed. In both cases the source of the 2, 4-dinitrophenyl group was 2, 4-dinitro-l-chloro-benzene. It is thought 0-(2, 4-dinitrophenyl) hydroxylamine is unstable under the acidic conditions in which it is formed. Model studies of the SN2 reaction of hydroxylamine and sodium methoxide with α-p-dichlorotoluene were performed to determine the optimal conditions for the synthesis of 0-(p-chlorobenzyl) hydroxylamine. The desired product was best synthesized by reacting five equivalents of hydroxylamine with one equivalent of α-p-dichlorotoluene in the presence of 0.66 equivalents of sodium methoxide. It is thought these conditions can be extended to the SNAr synthesis of 0-(2-nitrophenyl) hydroxylamine from 2-nitro-l-chlorobenzene, hydroxylamine and sodium methoxide.
Sommer, Richard Martin, "The synthesis of primary o-substituted hydroxylamines for the study of nucleophilic substitution at the electrophilic nitrogen center" (1975). Honors Theses. 1822.