Spectrophotometric determination of nickel with cyclohexylidine-ammonium 2-aminocyclohexylidene-1-cyclohexene-1-dithiocarboxylate

An (extraction)-spectrophotometric method is reported for the determination of nickel(II) with cyclohexylidineammonium 2-aminocyclohexylidene-l-cyclohexene-l-dithiocarboxylate. The violet 1:2 chelate is soluble in aqueous ethanolic or acetonic media at pH 6–9, or can be extracted into methyl isobutyl ketone. The molar absorptivity of the complex is about 2.5 × 10⁴ l mol^?1 cm^?1 at 550 nm.