Mesotomisat.ion of Diainm)no-dinitro-oxalr-coh)alt Complex. 9 



The mode of proceedure was quite the same as before; but in view 

 of the fact that the solubility of strychinine sulphate is considerably 

 less than that of brucine sulphate a slight modification was in- 

 troduced in taking a less concentrated solution of the barium salt 

 of the complex and in keeping its temperature at about 50°C, 

 instead of at 40''. The filtrate from the precipitated barium 

 sulphate soon yielded a quantity of pale brown needles, showing 

 that the strychinine salt of the complex is likewise much less 

 soluble than the corresponding brucine salt. 



An analysis of these crystals gave the following numbers: 



calc. for 

 obs. [Co(NH,)2 (NO.,),CA]-H-(C2iH,2NAVH2Ü 



Co = 9-60% Co=9-4:\% . 



H20=H.62 •• H20 = 2.88 " 



In the course of the fractionations of the strychinine salt of 

 the complex, it was observed that the least soluble fraction, which 

 contained ^strychinine-^diammine-dinitro-oxalo-cobalt complex, 

 was, in the state of a solution, even more unstable than the cor- 

 responding brucine salt; consequently, an accurate measurement 

 of its rotatory power in a dilute solution could not be made. The 

 strychinine salt after two recrystallisations was, therefore, converted 

 into the potassium salt in the manner already described, and the 

 specific rotation of the potassium diammine-dinitro-oxalo-cobaltiate 

 thus obtained was determined with the following result: 

 [a]g»=_104*' (0-\%, 10 cm) 



Due perhaps to the small solubility of the strychinine salt the 

 c^-variety of the complex could not be separated even by repeated 

 fractionations. 



4) Mesolomisalion of Diammine-dinitro-oxalo-cobalt 

 Complex as Cinchonine Salt. 



As the alkaloids used in the two preceeding cases were them- 

 selves laevorotatory, the optically active cobalt complex obtained 

 as the first fraction by using a salt of these alkaloids was also, in 

 each case, found to be laevorotatory. With the view, therefore, 



