Autoxidation of chloroform in air and sunlight

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript. Benzaldehyde readily undergoes autoxidation to form benzoic acid on exposure to air at room temperature. Yet it can be formed in high yield from, for example, benzyl alcohol by oxidation using a variety of procedures and catalysts. Here we report the evidence to resolve this apparent paradox. It is confirmed that benzyl alcohol (and a number of other alcohols), even at low concentrations in benzaldehyde, inhibits the autoxidation. Furthermore we report on the structural features required for inhibition. Electron paramagnetic resonance spin trapping experiments demonstrate that benzyl alcohol intercepts, by hydrogen atom transfer, the benzoylperoxy radicals that play a key role in benzaldehyde autoxidation. A similar inhibition effect has also been observed for the aliphatic octanal/1-octanol system. Selective oxidation is important in both academic research and in industry It has long been known that benzaldehyde spontaneously undergoes autoxidation to yield benzoic acid simply upon exposure to air at ambient temperature (~293 K) 2 pressure. The question has been posed previously and it has long been recognized that benzyl alcohol is one of a di...

A catalyst- and additive-free sunlight-induced strategy for autoxidation of a wide range of aldehydes to carboxylic acids is described for the first time. In this oxidation system, air serves as the source of oxygen and sunlight as the light source, which include the advantages of green, highly atom-efficient, and low-cost synthesis. This method was easily applied even at gram scale. The reaction proceeds smoothly even at lower temperature and in natural light. Catalyst- and additive-free sunlight-induced autoxidation of aldehydes to carboxylic acids H. Shi, J. Li, T. Wang, M. Rudolph and A. S. K. Hashmi, Green Chem., 2022, 24, 5835 DOI: 10.1039/D2GC01429G To request permission to reproduce material from this article, please go to the If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given. If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Read more about

Autoxidation is a conversion pathway that has the potential to add value to multinuclear aromatic-rich coal liquids, heavy oils and bitumens, which are typically considered low-value liquids. In particular, autoxidation of these heavy materials could lead to products that may have petrochemical values, e.g., lubricity improvers and emulsifiers. Proper assessment of an oxidative transformation to ring-open the multinuclear aromatics present in heavy feeds relies on the understanding of the fundamentals of aromatic oxidation. This work reviews the selective oxidation chemistry of atoms that form part of an aromatic ring structure using oxygen (O 2) as oxidant, i.e., the oxidation of aromatic carbons as well as heteroatoms contained in an aromatic ring. Examples of industrially relevant oxidations of aromatic and heterocyclic aromatic hydrocarbons are provided. The requirements to produce oxygenates involving the selective cleavage of the ring C–C bonds, as well as competing non-selective oxidation reactions are discussed. On the other hand, the Clar formalism, i.e., a rule that describes the stability of polycyclic systems, assists the interpretation of the reactivity of multinuclear aromatics towards oxidation. Two aspects are developed. First, since the interaction of oxygen with aromatic hydrocarbons depends on their structure, oxidation chemistries which are fundamentally different are possible, namely, transannular oxygen addition, oxygen addition to a carbon–carbon dou...