Tris amine, with cobalt compounds

The tris(Ar-hydroxethyIethylenediamine)cobalt(III) chloride that was used in these reactions was reported to be an orange crystalline solid (111). In a subsequent investigation (69), attempts to prepare this compound by the air oxidation of a mixture of cobalt (II) and the amine failed. The compound was, however, prepared by the displacement of ammonia from [Co(NH3)e]Cl3 by iV-hydroxyethylethylenediamine and a dark red compound was obtained. Attempts to react the hydroxy groups in this red complex with a variety of reagents (nitric acid, thionyl chloride, benzoyl chloride, and acetyl chloride) were as unsuccessful as the previously reported attempts to react the hydroxy groups in the orange cobalt complex. 

In mixed oximesarcophaginate [Co(tamox)]Cl(C104)2-H20 and [Co(tamox-H)]Cl2-3H20 semiclathrochelates whose symmetry resembles a TAP ( 52°), the Co-N(oxime) and Co-N(amine) distances are substantially different (co 1.90-1.91 and ca 1.97-1.98A, respectively). The observed N-0 distance (co 1.90A) in these compounds is appreciably greater than that of clathrochelate cobalt(III) tris-dioximates (ca 1.83A). This may account for unsuccessful attempts to prepare the corresponding clathrochelate complexes via cross-linking with boric and phenylboronic acids [182]. 

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