Metal-Free Synthesis of Unsymmetrical Organoselenides and Selenoglycosides

A one-pot, metal-free procedure has been developed to synthesize unsymmetrical organoselenides. In the first step of the reaction, arylation of potassium selenocyanate (KSeCN) with an iodonium reagent proceeds in the absence of a metal catalyst to produce an arylselenocyanate. In the second step, treatment with sodium borohydride unmasks a second selenium nucleophile that engages an aliphatic electrophile, iodonium reagent, or glycosyl halide. The procedure represents an umpolung approach to the synthesis of aryl-selenides.