Crystalline potassium boryl dithiolate and diselenolate

Both the B-S and S-S bonds of 1,2,4,3,5-trithiadiborolane 1 could be cleaved by potassium graphite (KC 8 ) to give the first isolable boryl dithiolate DmpB(SK) 2 3 , whereas the reduction of 1,2,4-triselena-3,5-diborolane 2 with KC 8 afforded the boryl diselenolate DmpB(SeK)(SeSeK) 4 , showcasing the unprecedented structural authentication of ligand substituted diselenolate. Reduction of 1,2,4-trichalcogena-3,5-diborolanes with KC 8 afforded the first isolable examples of boryl dithiolate and diselenolate.