Ammonium Salts by means of Tartaric Acid. 377 
made to apply other acids to the resolution of this salt, resulting 
in success with tartaric acid. 
Meanwhile Wedekind (Ber. 190G, xxxix. 4437) had come to 
the conclusion that the camphor-sulphonate had only been partially 
resolved and had reinvestigated the question. The rZ-brom- 
camphor-sulphonate was prepared but could not be resolved. The 
(Z-camphor-sulphonate was then submitted to a long series of 
fractional precipitations from chloroform solution by the addition 
of ether. Large quantities of material were used which rapidly 
diminished as the process was repeated. After thirteen pre- 
cipitations the value of [M] D for the salt was +116°; hence the 
basic ion has [M] D = G4°, the iodide in alcohol gave [M] D = 138 - 8° 
and 189° in chloroform. It is evident, however, that complete 
resolution in this way will be difficult. 
The acid cZ-tartrate was made in aqueous solution by mixing 
molecular proportions in the ammonium hydroxide (prepared from 
the iodide by the action of moist silver oxide) and tartaric acid 
and evaporating nearly to dryness at 100° C. The salt is then 
obtained as a sticky mass which soon crystallises on standing, it is 
sparingly soluble in ordinary organic solvents, but much more 
soluble in water, from which it could be recrystallised easily ; it is 
also easily recrystallised from hot rectified spirit. 
Recrystallisation from water did not effect resolution, but 
recrystallisation from rectified spirit heated to about 60° C. soon 
gave a salt which was lae vo-rotatory in aqueous solution and from 
which a laevo-rotatory iodide was precipitated. Finally, after about 
20 recrystallisations the salt appeared to be completely resolved as 
its specific rotatory power in aqueous solution remained constant 
at about — 59°. 
The salt on analysis was found to have a composition corre- 
sponding to C 6 H 5 . CH 3 . C 2 H 5 . C 7 H 7 . NC 4 H 5 0 6 + 2H 2 0 and melted 
at 90° to 93° C. 
The value of [M] D is therefore about — 240°, taking the value 
of [M] d for the acid tartrate ion as + 42° we get the value of 
[M] d for the basic ion = — 282°. 
This is still lower than that of the corresponding « -propyl ion, 
299°. 
The iodide was easily recovered from the aqueous solution of 
the tartrate by the addition of sodium iodide solution. It melted 
at 149° to 150° C. and had [M] D = — 312° in alcohol and —385° 
in chloroform. In chloroform the iodide gradually became inactive 
as all these iodides do. 
These results cannot yet be regarded as final, and the experi- 
ments are being repeated on larger quantities of the salt. The 
corresponding ally 1 compound has also been resolved by means of 
tartaric acid. 
