A Simple Method for the Efficient Synthesis of Unsaturated β-Dicarbonyl Compounds

Article abstract of DOI:10.1021/jo00327a016

β-Dicarbonyl compounds which are substantially enolized can be readily converted to their corresponding unsaturated derivative by (a) selenation using a 1:1 complex of phenylselenenyl chloride/pyridine and (b) in situ oxidation with 30percent H2O2 (after removal of the pyridine).The isolated yields of unsaturated β-dicarbonyl compounds obtained in this way are typically between 80percent and 100percent.If the selenation step (step a) is carried out in the presence of excess reagent, a slow ''nonoxidative'' elimination occurs.Synthetic and mechanistic details of this ''nonoxidative''process are discussed.