Oxidation of Selenides and Tellurides with Positive Halogenating Species

Article abstract of DOI:10.1021/jo01290a014

Treatment of diaryl or alkyl aryl selenides and diaryl or dialkyl tellurides first with a positive halogen source (N-chlorosuccinimide, tert-butyl hypochlorite) followed by alkaline hydrolysis (10percent sodium hydroxide, saturated sodium bicarbonate) gave the corresponding selenoxides or telluroxides (or hydrates) in good yield.The method is tolerant of a variety of functional groups including esters, olefins, alcohols, ethers, and ketones.The formal oxidation step is believed to be the formation of a chloroselenonium or chlorotelluronium species followed by hydrolysis. 1H NMR evidence is given for a benzylphenylselenonium species. Selenoxide fragmentation reactions during the hydrolysis step were observed