Hydrocyanation catalysts comprising aqueous solutions of at least
one water-soluble phosphine and nickel values, well suited for the hydrocyanation
of ethylenically unsaturated organic compounds such as diolefins, olefinic nitrites
and monolefins, are produced by (a) admixing an aqueous solution of such at least
one water-soluble phosphine with a nickel hydroxide, (b) adding hydrogen cyanide
or a compound which generates hydrogen cyanide to the mixture thus formed, (c)
stirring the resulting mixture until the nickel values have at least partially
dissolved, and (d) reducing at least a portion of said nickel values having an
oxidation state of greater than zero to the zero oxidation state.
