Potassium ethyl xanthate Potassium ethyl xanthate Potassium ethyl xanthate (KEX) is an organosulfur compound with the chemical formula CHCHOCSK. It is a pale yellow powder that is used in the mining industry for the separation of ores. Unlike the related sodium ethyl xanthate, the potassium salt exists as an anhydrous salt. Xanthate salts are prepared by the action of alkoxides on carbon disulfide. The alkoxide is often generated in situ from potassium hydroxide: Potassium ethyl xanthate is a pale yellow powder that is stable at high pH but rapidly hydrolyses at pH <9 at 25 °C. Unlike the sodium derivative, potassium xanthate crystallizes
Ethyl acetoacetate a bidentate ligand. For example, it forms purple coordination complexes with iron(III) salts: Ethyl acetoacetate can also be reduced to ethyl 3-hydroxybutyrate. Ethyl acetoacetate, when heated alone (uncatalyzed) with benzyl alcohol, forms synthetically useful benzyl acetoacetate (benzyl groups being easily removed later by catalytic hydrogenolysis over Pd/C under neutral conditions), via a mechanism involving acetylketene. Ethyl (and other) acetoacetates nitrosate readily with equimolar sodium nitrite in acetic acid, to afford the corresponding oximinoacetoacetate esters. A dissolving-zinc reduction of these in acetic acid in the presence of ketoesters or beta-diketones constitute the Knorr synthesis of pyrroles, useful for porphyrin synthesis. Ethyl