Synthesis of 3-Hydroxy-1-(p-methoxyphenyl)-2-methylpyridine-4-one and Spectrophotometric Extraction Studies on its Complexation of Vanadium(V)

Vesna Petrović Peroković,Srđanka Tomić,Astrid Gojmerac Ivšić,Željka Car

doi:10.5562/cca2366

Abstract

In this paper a single step synthesis of 3- hydroxy-1-(p-methoxyphenyl)-2-methylpyridine-4- one (HM) using starting maltol and p-anisidine in the presence of acid catalyst (p- toluenesulfonic acid or HCl) is described. The reaction is carried out by heating the aqueous solution of the reactants and a catalyst in a sealed thick-walled glass tube at 150 °C at different reaction times in order to retrieve an optimal yield. The complexation reactions of vanadium(V) with HM as well as the extraction of V(V) from aqueous to organic phase were studied spectrophotometrically. The optimum conditions for extraction of vanadium(V) from aqueous phase, containing chloride or thiocyanate ions, to chloroform solution of HM and complex formation have been evaluated. Based on the results obtained by Job’s and equilibrium shift methods the composition of the complexes has been found to be V(V) : Cl(SCN) : HM = 1:1:2.

Highlights

In this paper a single step synthesis of 3-hydroxy-1-(p-methoxyphenyl)-2-methylpyridine-4-one (HM) using starting maltol and p-anisidine in the presence of acid catalyst (p-toluenesulfonic acid or HCl) is described
In the environment vanadium occurrs in the (V) oxidized form, but in the body it can undergo changes in oxidation states and it can bind with blood protein, transferrin.[13]. It plays an important role in physiological systems including normalization of sugar levels and it has been reported that some vanadium complexes with pyran-4one and pyridin-4-one derivatives are suitable compounds for treatment of type 2 diabetes.[14,15]
In continuation of our work on the synthesis and properties of 3,4-HPO derivatives[11,19,20] and research in the field of coordinating capabilities of vanadium complexes[21] we report a single step synthesis of 3-hydroxy1-(p-methoxyphenyl)-2-methylpyridine-4-one (HM) which we optimized by using the adequate catalyst and appropriate reaction time to obtain the most satisfactory yield

Summary

Introduction

In this paper a single step synthesis of 3-hydroxy-1-(p-methoxyphenyl)-2-methylpyridine-4-one (HM) using starting maltol and p-anisidine in the presence of acid catalyst (p-toluenesulfonic acid or HCl) is described. 3-Hydroxypyridine-4-ones (3,4-HPOs) are a well known class of heterocyclic compounds extensively studied due to their broad field of application They possess strong chelating properties especially towards M(II)/M(III) ions, which is the basis for their applications as therapeutics[1] as well as selective extractants for certain metals.[2,3,4,5] So far, because of their chelating abilities, this group of compounds have shown the most promising results in the treatment of metal overload in humans[1,2,3,4,6] but they are not exclusive to such and similar therapies. The preliminary results presented in this work will be used for the development of a simple extractive-spectrophotometric method for the determination of trace amounts of vanadium in biological and environmental samples

Methods

Results

Conclusion