Electrochemical Flow α-Selenylation of 1,3-Dicarbonyl Compounds with Diselenides

Organoselenium compounds have attracted sustained interest because of their distinctive chemical reactivity and broad biological relevance. Selenium-mediated functionalization of carbonyls provides direct access to valuable selenium-containing building blocks. Herein, we report a simple electrochemical flow protocol for the α-selenylation of β-ketoesters using readily available diselenides. The reaction was developed in a commercially available undivided electrochemical flow cell using graphite electrodes and lithium perchlorate as supporting electrolyte. Systematic investigation of current, charge, flow rate, diselenide stoichiometry, and substrate concentration identified optimal conditions with a residence time of 4 min. Under these conditions, a range of paraand meta-substituted β-ketoesters underwent efficient αselenylation, providing the corresponding α-seleno derivatives in 60-85% yield. The method provides rapid access to synthetically useful αselenylated building blocks and highlights the potential of electrochemical flow technology for the preparation and subsequent telescoped synthesis of selenium-containing heterocycles.