217 



of cinchonine itself: the observed rotations appeared to be practi- 

 cally identical with those of the CLnchonine-l-rhodliuurmalonate, so 

 that evidently the influence of the three luolecnles of cinchonine 

 far ontweighs that of the laevogirate rhodiuni-malonate-ion itself. 



The last fractions of the crjstallisation-series of the cinc/tojiine-sa.\t 

 finally gave pnre cinchonine, a small amonnt of the dextrogyrate 

 salt and a certain qnantity of the racemic salt remaining in the last 

 mother-liquids. Evidently also here the repeated evaporation on (he 

 waterbath, just as in the case of the coiresponding o.valate, seemn to 

 cause a partial hydrolysis. Analysis taught us that the cinchonine- 

 d-rhodiuni-malonate crystallises with 3 //,(); the corresponding 

 cinchoni7ie-l-rJiodiwn-malonate with 7a H^O. This last mentioned salt 

 could not be heated above 100° C, being less stable than the right- 

 handed salt, it is rapidly decomposed with formation of a dirty 

 brown powder. 



For the rotation-dispersion of the cinchouine-ssdts we found the 

 following values: 



The solution investigated contained 0,3070 grams of the hydrated 

 salt in 100 grams of the liquid. 



The results obtained are plotted in the figure 1. It shows us, that 

 both curves are situated abot^e that of pure cinchonine, notwithstanding 

 the fact, that one of them contains the strongly negatively rotating 

 complex rhodium-malonate-ion ; of a simple superposition of the 

 optical activities there is therefore no question. 



The transformation of the ci?ichonine-SR\ts into the corresponding 

 potass ium-saUs was carried out in the following way. The pure 



