Effective asymmetric oxidation of enones and alkyl aryl sulfides

✍ Scribed by Melissa Hinch; Olivier Jacques; Carmelo Drago; Lorenzo Caggiano; Richard F.W. Jackson; Charles Dexter; Mike S. Anson; Simon J.F. Macdonald

• Book ID: 104056998
• Publisher: Elsevier Science
• Year: 2006
• Tongue: English
• Weight: 385 KB
• Volume: 251
• Category: Article
• ISSN: 1381-1169
• DOI: 10.1016/j.molcata.2006.02.006

✦ Synopsis

Asymmetric epoxidation of aliphatic enones can be achieved with good conversions and high levels of enantiomeric excess using a catalyst, formulated as 6, derived from dibutylmagnesium and a range of dialkyl tartrates, with tert-butylhydroperoxide as the oxidant. This process works best with the addition of small amounts of water and 4 Å molecular sieves, and can be scaled up to good effect. Optimisation of Bolm and Bienewald's vanadium-based method for asymmetric oxidation of alkyl aryl sulfides by aqueous hydrogen peroxide using Schiff bases derived from tert-leucinol as ligands, confirmed that the ligand 12 derived from 3,5-diiodosalicylaldehyde is the optimum choice.