213 



l-tuftrate crystallises first, being less soluble than the corresponding 

 d-turtrate. If qninicinc be used, the right tartrate crystallises first. 

 iv that time numerous fissions of racemic acids by im ;ui^ of 

 optically active bases have been made: the bases used were chi< fly 

 natural alcaloids, as: strychnine, brucine, morphine, quinine, cincho- 

 line, cinchonicine 1 ), etc., and more recently bases such as : ot-phenyl- 

 ethyl-amine 2 ), hydroxy-hydrindamine 3 ), etc. On the other hand, 

 many racemic bases are resolved by means of optically active 

 acids: d-tartaric acid, l-malic acid, and since 1898, when Pope 

 and Peachy 4 ) introduced some strongly optically active camphor- 

 derivatives for that purpose, especially by means of the camphor- 

 sulphonic, and the chloro-, resp. bromo-camphor-sulphonic acids. 



Thus lactic acid'. CH 3 CH(OH)COOH, was separated by Jung- 

 fleisch 8 ) by means of quinicine, and by Purdie and Walker 6 ) 

 by means of strychnine. 



Love'n *) separated oi-phenyl-ethyl-amine by means of l-malic 

 acid, while Pope and Read 8 ) made this fission by condensation 

 with d-oxymethylene-camphor. Ladenburg 9 ) in his famous syn- 

 thesis of coniine, was able to separate the obtained inactive base 

 into its optically active components by means of d-tartaric acid, 

 while Pope and Read 10 ) resolved hydroxy-hydrindamine by means 

 of the active a-bromo-camphor-Tr-sulphonic acid. The tri-ethylene- 

 diamine-cobalti-bromide : 



{Co(Eine) 3 } Br 3 + 3 H Z 0, 

 was resolved into its optically active components by Werner 11 ) 

 by means of its d-bromo-tartrate , and the same method can be used 



1) L. Pasteur, Jahresber. f. Chem. (1860), p. 250. 



2) W. J. Pope and J. Read, Journ. Chem. Soc. London 95. 172. (1909); 108. 

 451. (1913); J. M. Loven, Ber. d. d. Chem. Ges. 29. 2313. (1896); W. Marck- 

 wald and R. Meth, ibid. 38. 801. (1905). 



3) W. J. Pope and J. Read, Journ. Chem. Soc. 99. 2071. (1911); 101. 758. 

 (1912); 103. 447. (1913). 



*) W. J. Pope and S. J. Peachy, Journ. Chem. Soc. 78. 893. (1898); F. S. 

 Kipping and W. J. Pope, ibid. 63. 548. (1893). 



5) E. Jungfleisch, Compt. rend. 189. 56. (1904). 



) T. Purdie and J. W. Walker, Journ. Chem. Soc. London 61.754. (1892). 



7) J. M. Lov6n, Journ. f. prakt. Chemie (2). 72. 307. (1905). 



8) W. J. Pope and J. Read, Journ. Chem. Soc. 108. 451. (1913). 



9) A. Ladenburg, Ann. der Chemie 247. 85. (1886). 



10) W. J. Pope and J. Read, Journ. Chem. Soc. London 101. 758. (1912). 



11) A. Werner, Ber. d. d. Chem. Ges. 45. 121. (1911); F. M. Jaeger, Proceed. 

 Kon. Akad. van Wet. Amsterdam, 17. 1271. (1915). 



