PREPARATION OF SALT OF DIMERCAPTOMALEONITRILE

PURPOSE:To obtain the titled compound useful as a raw material for a germicide under mild conditions industrially advantageously, by dimerizing cyanodithioformate prepared from a salt of hydrogen cyanide and CS2 in a solvent under specific conditions at a specified temperature. CONSTITUTION:NaCN is used as a salt of hydrogen cyanide and reacted with CS2 according to the reaction formula, to give cyanodithioformate shown by the formula I . It is then dimerized in >=10 times as much a halogenated hydrocarbon (e.g., CHCl3, C6H5Cl, etc.) as it by weight at 60-120 deg.C, to give a salt of dimercaptomaleonitrile shown by the formula II. In the reaction, the amount of the solvent such as CHCl3, etc. is preferably 10-100 times, preferably 15- 30 times the compound shown by the formula I by weight.