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
2-Ethyl-1-butanol its presence helps reduce viscosity and lower freezing points. 2-Ethyl-1-butanol 2-Ethyl-1-butanol (IUPAC name: 2-ethylbutan-1-ol) is an organic chemical compound. It can be used to facilitate the separation of ethanol from water, which form an azeotrope that otherwise limits the maximum ethanol concentration. 2-Ethyl-1-butanol is manufactured industrially by the aldol condensation of acetaldehyde and butyraldehyde, followed by hydrogenation. It may also be prepared by the Guerbet reaction. The branching in 2-ethyl-1-butanol makes it harder to crystalize due to packing disruption, which results in a very low freezing point. Esters of 2-ethyl-1-butanol are similarly effected and it therefore finds application as a