Quinoxaline 1, 4-Dioxides. A Mechanistic Study of Their Formation and the Structural Assignment of 6(7) Isomeric Products

Author

Nicholas D. Alteri Jr., University of Rhode Island

Date of Award

1974

Degree Type

Thesis

Degree Name

Master of Science in Medicinal Chemistry

Department

Medicinal Chemistry

First Advisor

Elie Ahishab

Abstract

Two types of reactions were used to study the effect of substituents (CH₃, OCH₃) on the condensation of 5(6) substituted benzofurazan 1-oxides (1) with (methylthio)-2-propanone (BFO Reaction, A), and 4- substituted o-quinone dioximes (2) with pyruvaldhyde (OQD Reaction, B). The nitrogen atom is an electrophile in reaction A and nucleophile in reaction B.

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Thus, the same substituent is expected and does favor the formation of opposite ratios of 6:7 isomeric substituted quinoxaline hydroxamic acid esters (3). The ratios were determined from nmr spectra of these esters where the chemical shifts of the H-5 and H-8 protons, unlike their counterparts in quinoxaline 1, 4- dioxides, are assignable. The results are interpreted by assuming that benzofurazan 1-oxides react in their o-dinitroso tautomeric forms.

Recommended Citation

Alteri, Nicholas D. Jr., "Quinoxaline 1, 4-Dioxides. A Mechanistic Study of Their Formation and the Structural Assignment of 6(7) Isomeric Products" (1974). Open Access Master's Theses. Paper 1119.
https://digitalcommons.uri.edu/theses/1119