Potassium trioxalatocobaltate

Cobalt(III) trisacetylacetonate (in benzene) Potassium trioxalatocobaltate(III) Tricarbonatocobalt(III) nitrate... 

One gram (0.0012 mol) of i-tris(l,10-phenanthroline)-nickel(II) perchlorate 3-hydrate (synthesis 59) is dissolved in 18 ml. of a freshly prepared 1 1 by volume acetone-water mixture. The pink solution is cooled in an ice bath to 10° (not below) and added to an ice-cold solution of 1.10 g. (0.0023 mol) of potassium di-trioxalatocobaltate(III) 3-hydrate and 1 g. of potassium acetate in 20 ml. of water. The mixture is allowed to stand in an ice bath for 6 minutes with occasional stirring. Scratching the walls of the beaker may facilitate precipitation. The green diastereoisomer which precipitates is collected on a 5-cm. 

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