Process for the preparation of diazocyano acids by reacting keto-acids with cyanogen compounds

摘要

A process for the preparation of a diazocyano acid, which comprises reacting a keto-acid or its sodium salt with a cyanogen compound such as sodium cyanide or hydrogen cyanide and a hydrazine in water to form a concentrated aqueous solution of a hydrazo compound, adding acetone and/water to the concentrated aqueous solution to form a solution of the hydrazo compounds, adding chlorine gas to the solution to oxidize the hydrazo compound and form a diazocyano acid, adding acetone to the obtained reaction mixture during or after the oxidation if necessary, and separating and recovering the supernatant layer of the acetone-water solution containing the diazocyano acid from the mixture.