Study the Effect of Molecular Conjugation of Some Hydroxamic Acid Derivatives on the Chemical and Physical Properties.

Abstract

In this research, the following hydroxamic acid compounds (D1, D2, D3, D4, D5) were
prepared through direct interaction between the primary esters of these compounds with
hydroxylamine hydrochloride in an alkaline medium at (PH 12-13) using a strong base such
as hydroxide Sodium The formation of hydroxamic acids was detected using the ferric ion as
a primary reagent, and we infer that through the appearance of a pinkish-red color.
The precipitate was filtered and recrystallization was carried out for purification. Also, the
prepared compounds were dried and characterized using UV-Vis spectra, as well as FT-IR,
(H1-NMR) and (C13-NMR).
The chemical and physical properties of the prepared hydroxamic acid compounds were
studied by treating them with some metal ions such as (Fe+3, Cu +2, Co +2), where it was
found that these compounds interact with the ferric ion only, giving colored complexes, while
no interaction with ions occurred. Cobalt and copper, and we infer through that that the
compounds (D1, D2, D3, D4, D5) are bi-toothed and selective chelating compounds.
Likewise, the Hammett equation was used to study the effect of molecular coupling of
hydroxamic acid compounds, by determining the dissociation constants for the prepared
hydroxamic acids, using the equations:
∂ X= log K – log (Ka0)
= PKa + (pka0)
p = log