Chemistry Proceedings

Organocalcogenides, in particular, organoselenium compounds, have been widely studied due to their large number of synthetic and biological applications. Among organoselenium compounds, a class of bis-selenide-alkene derivatives has attracted attention. Recently, some studies have been developed for the synthesis of vinyl chalcogen derivatives, since these are also highly valuable intermediates in several synthetic applications. However, the methodologies developed so far have extensive reaction times, and use toxic solvents as well as heavy metals. Therefore, there is an emerging need to develop protocols for the synthesis of these molecules that are in accordance with the principles of green chemistry. In this work, we developed an alternative synthesis of bis-selenium-alkene derivatives, through an environmentally appropriate methodology. Reaction optimization was evaluated from the diphenylacetylene and diphenyl diselenide, using I₂/DMSO as a catalytic system under microwave irradiation or conventional heating. The variations of these conditions were carried out through different equivalences between the reagents, the amount of catalyst (I₂), temperature, DMSO and the reaction process (Microwave or conventional). Even now, it was found that the best established condition was using diphenylacetylene, diphenyl diselenide, 30 mol% I₂ in DMSO, under microwave irradiation at 100 °C for 10 min. In this condition, the product was obtained in 82% yield and its characterization was performed using 1H and 13C NMR spectroscopy. Therefore, the methodology that is being developed, in addition to perfectly attending to the principles of green chemistry, will allow to evaluate the reaction scope using different alkenes and diselenides or even disulfides and ditellurides. Full article