IV. 



CONTRIBUTIONS FROM THE CHEMICAL LABORATORY OF 

 HARVARD COLLEGE. 



THE ACTION OF FLUORIDE OF SILICON ON 

 ORGANIC BASES. 



By Arthur M. Comey and C. Loring Jackson. 



Presented June 15, 1887. 



The research described in the following paper was undertaken in the 

 hope of obtaining from the amines products similar to the compound 

 which ammonia gives with fluoride of silicon, (NH„) 2 SiF 4 , discovered 

 by Gay-Lussac and Thenard,* and three years later prepared and 

 studied by J. Davy.f We have been able to find only two previous 

 papers on this subject, one published by Laurent and Delbos,$ in 

 1848, in which the action of fluoride of silicon on aniline is described, 

 the product being a nearly white mass, which they washed with ether, 

 boiled with alcohol, and sublimed to purify it for analysis ; their analy- 

 ses, however, led only to a very complex formula containing oxygen, 

 which they advance " with much reserve," although it was confirmed 

 by the proportions § in which its factors combined. The substance 

 when treated with water gave a gelatinous precipitate of silicic acid, 

 and when boiled with alcohol was converted into small white lustrous 

 scales.|| The second paper was published by W. Knop,** in 1858, and 

 had for its primary object the study of the solution of fluoride of sili- 

 con in absolute alcohol, which gave with urea and aniline the fluosili- 

 cates of these bases, both of which Knop sublimed, and obtained from 



* Mem. d'Arcueil, ii. 317. 



t Phil. Transact., 1812, p. 352. 



$ Ann. Chim. Phys., ser. 3, xxii. 101. 



§ These proportions agree tolerably with the formula worked out by us for 

 this substance, but their analytical results do not, and are entitled to no con- 

 sideration, on account of the difficulties in the analysis, which Laurent and 

 Delbos did not succeed in overcoming. 



|| Aniline fluosilicate. 



** Chem. Centralblatt, 1858, p. 388. 



