PEEL EXTRACT ASSOCIATED OXIDATIVE GREEN DAKIN SYNTHESIS OF SOME PHENOLS USING AQUEOUS BANANA EXTRACT CATALYST

Ishwari A Kale,Bhagwan K Sakhale,Dattatraya N Pansare,Kshipra S Karnik,S N Sinha,Arjun L Khandare,Nileema S Gore,Aniket P Sarkate

doi:10.17628/ecb.2019.8.160-163

Abstract

The green Dakin reactions can be performed by employing gallic acid as an oxidizing agent. Implementation of gallic acid helps to avoid the usage of catalyst, ligand and any toxic or hazardous oxidizing agent. Gallic acid accelerates the conversion of the atmospheric oxygen into hydrogen peroxide, which helps in the oxidation of aldehydes in situ . Mango peel, potato peel, pomegranate pomace, grape pomace extract contains the rich source of gallic acid that performs the oxidations in a natural feedstock. The best results were obtained by mango peel as well as potato peel extract giving excellent yields with minimum time at room temperature. The ‘aqueous extract of banana’ (AEB), in the said conversion plays a dual role of catalyst and a base. The reported work can be considered as environment-friendly Dakin oxidation, as it is carried out in a neat AEB at room temperature under aerobic conditions with low reaction time and better yield.

Highlights

Nowadays, green chemistry or development of sustainable processes in chemical synthesis plays a vital role to eradicate the hazardous organic solvents or any other toxic metal-based chemical reagents[1]
Chlorogenic acid (CGA) is the main content of potato peel which is a part of phenolic acids along with gallic acid (GAC), caffeic acid (CFA) and protocatechuic acid which are present in low amounts[5]
Our investigation initiated by the literature survey was found that Dakin oxidation of benzaldehyde to phenols was carried using H2O2 and aqueous extract of banana (AEB) as a neat reaction media at room temperature

Summary

Introduction

Green chemistry or development of sustainable processes in chemical synthesis plays a vital role to eradicate the hazardous organic solvents or any other toxic metal-based chemical reagents[1]. In the case of fruits and vegetables, usually, a high amount of antioxidant compounds is found in peels, kernels or seeds, namely in parts that are removed during processing and become wastes[2]. Grapes contain a large amount of polyphenols which include the phenolic acids, flavonoids, anthocyanins and proanthocyanidins[7]. The quantification of individual phenolic acids, stilbenes, flavonoids including anthocyanins, was done for the comparison of the novel process with conventional pomace extraction[9]. Phenolic compounds are secondary metabolites, ubiquitous in plants and plant-derived foods and beverages They show a large diversity of structures, including rather simple molecules (e.g., vanillin, gallic acid, caffeic acid), and polyphenols such as stilbenes, flavonoids, and polymers derived from these various groups[10]. The use of an abundant and underutilized bio-waste, such as grape pomace, in sustainable oxidations with air has been explored

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Results

Conclusion