Patent ID: 8222445
Filing Date: 2012-07-17
Classification: C07C

Abstract:
1. Process for preparing alkali metal or alkaline earth metal tricyanomethanides in a purity of at least 99% by weight, comprising the steps of a) reacting malononitrile, which has been deprotonated in the presence of an alkali metal base or alkaline earth metal base, with a cyanogen halide in an aqueous solvent mixture comprising at least one organic solvent and water at not more than 35° C.; b) separating precipitated alkali metal or alkaline earth metal halide; and c) distilling the aqueous solvent mixture so that the alkali metal or alkaline earth metal tricyanomethanide precipitates; wherein the alkali metal or alkaline earth metal base is selected from the group consisting of lithium, sodium, potassium, calcium, magnesium and barium bases.