Ethyl cyanohydroxyiminoacetate Ethyl cyanohydroxyiminoacetate Ethyl cyanohydroxyiminoacetate (oxyma) is the oxime of ethyl cyanoacetate and finds use as an additive for carbodiimides, such as dicyclohexylcarbodiimide (DCC) in peptide synthesis. It acts as a neutralizing reagent for the basicity or nucleophilicity of the DCC due to its pronounced acidity (pKa 4.60) and suppresses base catalyzed side reactions, in particular racemization. Ethyl cyanohydroxyiminoacetate is obtained in the reaction of ethyl cyanoacetate and nitrous acid (from sodium nitrite and acetic acid) in 87% yield. Because of the rapid hydrolysis of the ester, the reaction should be carried out at pH 4.5, in buffered phosphoric acid the
Ethyl nitrate formed by natural processes. Ethyl nitrate has been prepared by bubbling gaseous nitryl fluoride through ethanol at −10 °C. The reaction was subsequently studied in detail. Ethyl nitrate can be prepared by nitrating ethanol with fuming nitric acid or a mixture of concentrated sulfuric and nitric acids. Further purifying by distillation carries a risk of explosion. Ethyl nitrate Ethyl nitrate is the ethyl ester of nitric acid and has the chemical formula . It is a colourless, volatile, highly flammable liquid. It is used in organic synthesis and as an intermediate in the preparation of some drugs, dyes, and perfumes.