1223 
dodecamine-hewol-tetra-cobaltibromide*), whieh salt has the same type 
as the triethylenediamine-cobalti-salts, but no longer possesses one 
single carbon-atom. 
$ 4. As suitable objects for this investigation 1 have chosen the 
luteo-triethylenediamine-cobalti-salts of the type: {Co (Aein),} X,, in 
which X was varied in several ways, for the purpose of elucidating 
as well as possible the mere influence of the complex cation. | 
prepared these salts, starting from the already obtained optically 
active components of the corresponding bromide, and by making 
them react in aqueous solution with the silversalts of nitric acid, 
chloric acid, perchloric acid, ete., or by double decomposition with 
the potassium-, or sodiumsalts of hydrojodie or rhodanie acid. The 
optically active bromides themselves were obtained from the racemic 
salt by means of the corresponding bromotartrates, whose dextro- 
gyratory form is also described in the next paper. The great stability 
of the active components, even when heated in aqueous solution, 
was of preponderant importance in these experiments; an autorace- 
misation does not occur in any appreciable degree. 
The racemic salt was prepared by two different methods: 1. 
bv starting from  praseo-diethylenediamine-dichloro-cobalti-chloride : 
Co (Aein), 
Cl, 
and 2. by starting from  purpureo-pentamine-chloro-cobaltichloride : 
Co oe Cl, and transforming it by boiling it, for a longer 
time with ethylenediamine. This last method of preparation, described 
by Prremrer’), was also followed, because the description of the 
obtained salt by this author differs in some particulars from that, 
given with respect to the salt obtained in the first mentioned method. 
However by a more detailed comparison of the two products it was 
clearly pointed out, that notwithstanding slight differences in the 
external habitus of the racemic salt in the two cases, the optically active 
products were perfectly identical; and that tie preparations obtained 
by the two methods, must undoubtedly be considered as quite the 
same. (Vid. publication II). 
With respect to the isomerism ie, this can in all cases be illu- 
strated for the complex cation by means of the following perspective 
drawings, (fig. 1), which can be constructed immediately, starting 
| Cl, and heating with a 10 °/,-solution of ethylenediamine ; 
1) A. WERNER. loco cit., 3093 (1914). 
2) Preirer, Ann. der Chem. 346, 59, (1906). 
