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
2-Ethyl-2-oxazoline one-pot reaction propionic acid is converted first with 2-aminoethanol to 2-hydroxyethylamide, than reacted with boric acid at 130 °C yielding a boric acid ester which is finally thermolyzed at 280 °C in 92% yield to 2-ethyl-2-oxazoline. From propionic acid and thionyl chloride can be obtained propanoyl chloride, which reacts with ethanolamine in the presence of an acid scavenger (for example pyridine) to N-propionyl-2-aminoethanol. With further thionyl chloride this reacts further to 2-chloroethylamide. With the chloride ion as a better leaving group, this intermediate is cyclized by simple heating to the oxazoline. Water must be excluded du to the tendency of