PREPARATION AND PROPERTIES OF SOME ALKANE-SOLUBLE LIQUID TRANSITION-METAL COMPLEXES

A series of nickel(II) compounds have been prepared which are derivatives of reported β-diketonates, N,N-dithiocarbamates, or O,O′-dithiophosphates. The transition metal ton complexes reported here are unusual in that they are liquids or low melting waxes that are very soluble in hydrocarbon solvents such at pentane and squalane. Because of their properties, techniques used for the isolation and subsequent purifftcation of the complexes are different than those employed for the lighter homologues. The ligand substituents profoundly affect the propertim of the compounds. In contrast to the reported complexes, the ntckel(II) bis-β-diketonates prepared in this study undergo the monomer-trimer transition close to room temperature. For example, in the compound in which the methyl groups of nickel(II) acetylacetone are replaced by n-heptyl groups, the transition from diamagnetic purple solid monomer to paramagnetic green liquid trimer occurs at about 17°C. It occurs at 42°C for the n-nonyl derivative. The t-nonyl (1,1-dimethylheptyl) derivative melts at +2°C since the bulky groups adjacent to the carbonyls prevent trimer formation and hinder crystallization. © 1979.