Basic Ionic Liquid [Bmim]OH as Efficient Greener Medium for the Oxidation α-Hydroxy Ketone Compounds and Alcohols to Carbonyl Compounds with Potassium Permanganate

In this work, a convenient and greener procedure for synthesizing 1,2-diarylethane-1,2-dione derivatives as well as the oxidation of primary and secondary alcohols was explored using an oxidizing agent (KMnO4) in a basic ionic liquid of 1-butyl-3-methylimidazolium hydroxide ([Bmim]OH) as greener medium. The selective oxidation of α-hydroxy ketone compounds together with primary and secondary alcohols in the presence of KMnO4 in [Bmim]OH afforded corresponding carbonyl compounds of 1,2-diarylethane-1,2-dione derivatives and aldehydes or ketones in high yields (85-97% and 83-97%, respectively). The reactions are mild, fast, and efficient. Moreover, KMnO4 in [Bmim]OH medium was easily recovered and reused for at least four additional reactions without significant loss of efficiency with a consistent yield of about 80%

Advancements in N-heterocyclic carbenes (NHCs) catalysis for benzoin reactions: A comprehensive review from past to present

N-heterocyclic carbenes (NHCs) catalyze benzoin condensation, which is a unique carbon-carbon bond-forming reaction. It entails a coupling reaction between two aldehydes catalyzed by NHCs that produce a-hydroxycarbonyl compounds (acyloins). NHCs have emerged as a potent class of organocatalysts, catalyzing numerous benzoin and benzoin-type reactions. This review provides an overview of the historical development of NHCs and their application in benzoin reactions. Additionally, recent advancements in NHC catalysis, including the use of chiral NHCs, are discussed. This review aims to provide a comprehensive understanding of the current state of NHC catalysis for benzoin reactions and its potential for future developments in synthetic chemistry

High pressure systems as sustainable extraction and pre‑treatment technologies for a holistic corn stover biorefinery

This mini-review assesses supercritical carbon dioxide (scCO2) extraction and high-pressure carbon dioxide pre-treatment technologies for valorisation of corn stover agricultural residues with particular focus on showing how these can aid in the creation of a holistic biorefineries. Corn stover is currently the largest source of agriculture residues in the USA, as such there is significant potential for exploitation to yield valuable chemicals. ScCO2 extraction could lead to the recovery of a variety of different chemicals which include flavonoids, sterols, steroid ketones, hydrocarbons, saturated fatty acids, unsaturated fatty acids, fatty alcohols, phenolics and triterpenoids. Importantly, recent studies have not only demonstrated that supercritical extraction can be utilized for the recovery of plant lipids for use in consumer products, including nutraceuticals and personal care, but the processing of treated biomass can lead to enhanced yields and recovery of other products from biorefinery processes. Despite the great potential and opportunities for using scCO2 and high-pressure systems in a biorefinery context their real-world application faces significant challenges to overcome before it is widely applied. Such challenges have also been discussed in the context of this mini-review.peer-reviewe