Investigation on stereoconfiguration of azoxybenzene formed via Grignard reaction and further Consequences on Z & E isomerism of diazeniumdiolates

Abstract

Nitric oxide’s importance in biochemistry was recognized in the mid 1980’s. Nitric oxide (NO) is critical for the function of neuronal cells, for blood flow and to defend against tumour cells and microorganisms. Diazeniumdiolates, ions of structure [RN(O)NO]-, are being used as probes to study the biological and pharmacological implications of NO because compounds bearing this functional group have been found to release NO. The conformation about the N=N double bond of diazeniumdiolates has been shown through crystallographic studies to be predominantly Z. To study the stereospecificity of diazeniumdiolates, azoxybenzene was synthesized via a “forgotten” synthetic pathway pioneered by Stevens in 1963 which involved a reaction between an organonitrosohydroxylamine tosylate, RN(O)NOTs, and a Grignard reagent. The product from this preparation was directly compared to azoxybenzene made from a coupling reaction.