Strained dimethyl 2-(bromoselanyl)-5-tert-butylisophthalate: a reactive precursor for the synthesis of ebselen analogs

A facile synthesis of ebselen analogs, having Se⋯O(ester) secondary bonding interaction, is described. The reaction of dimethyl 2-(bromoselanyl)-5-tert-butylisophthalate (4) with different diprotic amines such as ethanolamine, 2-chloroethylamine, and N,N′-dimethylethylenediamine afforded the ebselen analogs. Reaction of 4 with ethylenediamine and tris(2-aminoethyl)amine resulted in the formation of bis- and tris-ebselen derivatives, respectively.