Emerald-green crystals; orthorhombic structure; density 1.455 g/cm3 at 17°C; melts at 230°C; soluble in water, alcohol, chloroform, benzene and toluene; insoluble in ether.
Nickel acetylacetonate is prepared by the reaction of acetylacetone with nickel chloride hexahydrate or nickel hydroxide, followed by crystallization:
2CH3C(=O)CH2C(=O)CH3 + Ni(OH)2 → Ni(CH3C(=O)CHC(=O)CH3)2 + 2H2O
light green powder
Nickel acetylacetonate is used as a catalyst in hydrogenation and other organic reactions.
Wash the green solid with H2O, dry it in a vacuum desiccator and recrystallise it from MeOH. [Charles & Pawlikowski J Phys Chem 62 440 1958.] The complex can be conveniently dehydrated by azeotropic distillation with toluene, and the crystals may be isolated by concentrating the toluene solution. [Wilkinson et al. J Am Chem Soc 76 1970 1954, Beilstein 1 IV 3677.]