Efficient Baeyer-Villiger electro-oxidation of ketones with molecular oxygen using an activated carbon fiber electrode in ionic liquid [bmim][OTf

Y L Hu,D J Li,Y B Xie

doi:10.4314/bcse.v30i2.14

Abstract

A new and efficient method for the synthesis of lactones and esters involving the application of an molecular oxygen-based electro-catalytic oxidation system and ionic liquid [bmim][OTf] as electrolyte has been developed. The reaction between various ketones with molecular oxygen proceeds in a three-electrode cell under constant current conditions in [bmim][OTf] at room temperature to give the corresponding esters and lactones in good to excellent isolated yield. Additionally, the possible mechanism of Baeyer-Villiger oxidation of ketones in the electro-catalytic system is proposed. KEY WORDS : Baeyer-Villiger oxidation, Ketone, Molecular oxygen, Electrocatalysis, Ionic liquid Bull. Chem. Soc. Ethiop. 2016 , 30(2), 297-306. DOI: http://dx.doi.org/10.4314/bcse.v30i2.14

Highlights

Lactones and esters are important classes of chemicals that have been used extensively as synthetic intermediates in the preparation of a variety of fine or special chemicals such as drugs, steroids, pheromones, etc [1, 2]
A mixture of [bmim][OTf] (20 mL) and ketone (0.1 mol) in a three-electrode cell fitted with activated carbon fiber as the anode and Pt cathode was subjected to electro-catalytic oxidation at a constant current at room temperature for an appropriate time
Preliminary studies were performed using acetophenone as the model substrate on an activated carbon fiber (ACF) electrode in the presence of ionic liquid [bmim][OTf] electrolyte to examine the effects of various reaction parameters on the typical oxidation (Table 1)

Summary

Introduction

Lactones and esters are important classes of chemicals that have been used extensively as synthetic intermediates in the preparation of a variety of fine or special chemicals such as drugs, steroids, pheromones, etc [1, 2]. A mixture of [bmim][OTf] (20 mL) and ketone (0.1 mol) in a three-electrode cell fitted with activated carbon fiber as the anode and Pt cathode was subjected to electro-catalytic oxidation at a constant current at room temperature for an appropriate time.

Results

Conclusion