Jones Oxidation

In 1946, E.R.H. Jones and colleagues reported the synthesis of alkynyl ketones from their corresponding carbinols using chromic acid (chromic trioxide mixed with diluted sulfuric acid) without oxidizing their sensitive triple bond. Since then, the oxidation of primary and secondary alcohols with chromic acid became known as the Jones oxidation. Chromic acid can be prepared by mixing chromium trioxide (CrO₃) or dichromate salts with either sulfuric or acetic acid. The oxidation is generally carried out using acetone as the solvent, as it reacts with excess oxidant to prevent over-oxidation of the substrate.

For highly acid-sensitive substrates, several milder chromium oxide-based reactions have been developed, including the Sarett and Collins oxidations. The Sarett oxidation uses pyridine as the solvent, while the Collins oxidation utilizes a complex of chromium(VI) oxide with pyridine in dichloromethane.

The Jones oxidation has been used in several successful total synthesis campaigns such as the first synthesis of the polyketide (-)-solanapyrone E and the alkaloid (-)-dendrobine.