Optically active co-ordination compounds. Part V. The method of less-soluble diastereoisomers and relative configurations

Abstract

The solubilities of diastereoisomeric salts of complexes of cobalt(III) of the type [Co en₂XY]ⁿ⁺ with optically active anions are investigated. The resolutions of the ions bisamminebisethylenediaminecobalt(III) and bromoaquobis-ethylenediaminecobalt(III) have been achieved using (+)-antimonyl tartrate salts. The application of the method of less-soluble diastereoisomers in relating optical configurations is discussed, and Jaeger's rule is adopted, that only isomorphous diastereoisomers should be compared; an extension is made to complexes containing optically active ligands. Previous applications are discussed critically. A number of reliable correlations are given, between complexes of cobalt(III) and those of other tervalent metals.