Diaquabis ethylenediamine cobalt III Bromide

Twenty grams (0.0535 mole) of crude cir-aquabis(ethylene-diamine)hydroxocobalt(III) dithionate (preparation F) is dissolved in 60 ml. of ice-cold (0-5°C.) 1 M hydrobromic acid. To the 

To prevent substitution by bromide, the sample is kept in a refrigerator at —15°C. At this temperature it is stable for some months. The above crude product of the bromide salt is contaminated with a negligible amount of cts-aquabromobis-(ethylenediamine)cobalt(III) bromide, which is not removed by reprecipitation. However, the bromide salt has a purity suitable for further synthetic work, e.g., preparation of cis-aquabis(ethylene-diamine)hydroxocobalt(III) bromide.12 

The visible absorption spectrum in acidic solution differs slightly from the spectrum of the pure as-diaqua complex.t Found in 0.12 M perchloric acid (76.3, 492), (60.8, 358)  

Submitted by ROBERT D. HARGENS, WOONZA MIN, and ROBERT C. HENNEY Checked by T. M. BROWNf and A. GALLIARTf 

Disodium cw-bis(ethylenediamine)disuIfitocobaltate(III) nitrate and also the perchlorate have not been reported before and are recommended as sources of the cfs-bis(ethylenediamine)disulfito-cobaltate(III) ion, which has been prepared by Baldwin1 by proceeding through a difficult series of complex salts. The m-azidobis(ethylenediamine)sulfitocobalt(III) is also newly reported it can be converted into a relatively pure sodium ran.y-bis(ethylenediamine)disulfitocobaltate(III), which has previously been made from dichlorobis(ethylenediamine)cobalt(III) chloride1 and tetraammine(carbonato)cobalt(III) chloride.2 

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