BY MEANS OF CATALYSTS. CREIGHTON. 25 



Synthetic camphor, the weak dextrio-rotation of which was 

 compensated with the necessary amount of 1- camphor, was 

 used to prepare a hromcampJior-car'boxyUc acid which was 

 completely inactive. This acid was used for the following 

 activation experiments. 



1. With, ciuinine. Since with this alkaloid the 1- acid 

 decomposes more rapidly than the d- acid, one should expect 

 that the undeoomposed acid on the one hand would be laevo- 

 rotatary, and on the other the bromcamphor, which is formed 

 by the reaction, would be dextro-rotatary. 



From the decomposition curve it is found that the mo&t 

 favourable moment for stopping the reaction is at the end of 

 68 minutes. Two parallel experiments were made. 5.0000 

 grams of inactive bromcamphor-carboxylic acid were dissolved 

 in 50 ccm. of acetophenone and mixed with 5 ccm. of aceto- 

 phenone which contained 0.1000 gram of quinine. The mixture 

 was jDlaced in a .thermostat and kept at 40° for 68 minutes, at 

 the end of which time it was mixed with 10 ccm. of a dilute 

 solution of hydrochloric acid and buried in a freezing mixture 

 of salt and ice. The hydrochloric acid was previously saturated 

 with common salt so as to cause the layer of the acid solution 

 to separate from the acetophenone solu-tion moie ouickly. The 

 addition of the hj^lrochloric acid solution served the double 

 l^urpose lof stopping the reaction and removing the quinine 

 The optical rotation of the hydrochloric acid solution, after 

 separation from the acetophenone layer, was measured is a 

 1 dcm. tube and found to be: — 1°99. The acteophenone 

 solution was shaken up twice again with 10 ccm. of the 

 hydrochloric acid. The second HCl extract when polarised 

 in a 1 dcm. tube was found to give a rotation of ^ — 0°.02 ; while 

 the third extract gave a rotation of: 0°.00. 0.1000 gram of 

 quinine was dissolved in 10 ccm. of the above HCl solution 

 that was used for extracting the quinine from the 

 reaction mixture ; this when polarised in a 1 dcm. 

 tube and was found to give a rotation of — 1°.96, thus 

 showing that one shaking with 10 ccm. of the HCl solution 



