Síntese de 5H-selenofeno[3,2-c]isocromen-5-onas a partir de disselenetos de dialquila e 2-(organoilbuta-1,3-diin-1-il)benzoatos de metila promovida por Oxone®

Abstract

In the present work, a methodology for the selective synthesis of isochromenones fused to selenophenes nucleo, through the reaction between dialkyl diselenides and methyl 2-(organylbuta-1,3-diyn-1-il)benzoates in the presence of Oxone® and in ethanol as solvent. 5H-Selenophene[3,2- c]isochromen-5-ones were obtained via intramolecular electrophilic cyclization. The electrophilic selenium species were generated in situ by the oxidative cleavage of the Se–Se bond in dialkyl diselenides by Oxone®. Thus, through the protocol developed, it was possible to synthesize twelve examples of 5H- selenophene[3,2-c]isochromen-5-ones in a satisfactory manner (40-86%) in ethanol as solvent under reflux, in open flask and at short reaction times (1.0-3.0 h). The used diselenides were diethyl, dibutyl and dioctyl diselenide and the methyl 2-(oganoylbuta-1,3-diyn-1-yl)benzoates had the substituents: C6H5, 4- CH3OC6H4, 2-CH3OC6H4, 4-CH3C6H4, 2-CH3C6H4, 4-ClC6H4, C4H9 and naphthyl.