Convenient Michael addition/β-elimination approach to the synthesis of 4-benzyl- and 4-aryl-selenyl coumarins using diselenides as selenium sources

A concise and efficient, two-step approach toward 4-organoselenyl coumarin derivatives from the easily available 4-hydroxycoumarins, is reported. The synthesis was based on conventional tosylation followed by a tandem selena-Michael addition/beta-elimination reaction of an aryl-/benzyl-selenolate anion on the corresponding 4-tosyloxycoumarins. The selenolate anions were conveniently generated in situ by exposure of the corresponding diselenides to NaBH4. Selected compounds demonstrated to exhibit antioxidant properties in mice cortex and hippocampus. (C) 2017 Published by Elsevier Ltd.