α-Arylchalcogenation of Aldehydes and Ketones with Diaryl Dichalcogenides Promoted by K3PO4

Due to wide synthetic utility of α-phenylseleno carbonyl compounds, and α-sulfenyl ketones, much effort has been devoted to accomplish the synthesis of these compounds. For example, α-phenylseleno aldehydes and ketones can be converted into the corresponding synthetically useful α,β-unsaturated carbonyl compounds through selenoxide elimination reactions. In addition, these compounds can be transformed into other important organic intermediates such as amines, α-amino acids, allylic alcohols, aziridines, and α-hydroxy esters. Several procedures have been developed for the preparation of α-phenylseleno aldehydes and ketones, including: reaction of electrophilic organoselenium reagents with aldehydes, ketone enolates or enolate derivatives, nucleophilic reaction of phenylselenolates with α-halo aldehydes or ketones, and insertion of elemental selenium into zinc carbon bond. Herein, we have developed a new convenient and efficient protocol for α-arylchalcogenation of aldehydes and ketones with diaryl dichalcogenides in the presence of K3PO4 under mild reaction conditions with good to high yields. This process represents a suitable option to existing methods.