Nickel complexes absolute configuration

Werner resolved the tris oxalate using strychninium ion in 1912. Other effective resolving agents for the tris complex include (+ )-tris(l,10-phenanthroline)nickel(II), ( + )- or (- )-tris(ethylenediamine)cobalt(III) and (- )-tris(ethylenediamine)rhodium(III). The (- )-[Co(ox)3] ion has been studied by single-crystal methods and has the d configuration. It has been related to (-i-)-[Cr(ox)3] by X-ray powder photography, so its absolute configuration is also established as d by the more exact form of the rule of least-soluble diastereoisomers. ... 

A recent interesting application of solvent effects has been the use of optically-active solvents in the determination of the optical purity and the absolute configuration of solutes. Work so far has centred on resonances and organic solutes, covering various alcohols, amines, sulphoxides, a-hydroxy- and a-amino-acids, and epoxides (the solvent here being an optically active nematic phase ). There are also reports on disymmetric nickel(II) complexes, and the use of resonances. ... 

Other Metals. Complexes of Pt(II), Pt(IV), Ni(II), and Co-balt(III) have been surveyed. Results appear in Table V. In the cases of Pt and Co compounds, examples of differential lethality are observed. In the case of the two nickel compounds, no activity is observed despite the fact that both are relatively inert to ligand substitution. In the case of the cobalt(III) complexes, the absolute configuration of the complex affected the differential lethality, with the (-)tris(ethylenediamine)cobalt(III) cations considerably less active than the (+) complex. 

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