^1oHg\ 



Quanti valence of Oxygen. 413 



cordance with the preset 



N (a) H 



be written, in accordance with the present suggestion, as 

 follows : — 



l>N.C 6 H 5 



08) 



H 



(a) 



C 10 H 6 <|>N.C 6 H 5 

 N OS) 



I. 



II. 



I. Produced by the action of diazobenzene salts on /3-naphthol. 

 II. Produced by the action of phenylhydrazine on /3-naphtha- 

 quinone. 



The proposed formulas account for the formation of a-amido- 

 /3-naphthol and /3-amido-a-naphthol respectively on reduction. 

 The insolubility in alkali appears from the fact that the H-atoin 

 is not hydrod'ylic, but attached to an oxygen atom which forms 

 part of a closed chain. This explains also why the /3-azo- 

 compounds are more stable, and are so much less readily alky- 

 lated or acetylated than the a-derivatives. 



The views which I have here advanced may be extended 

 to all amidoazo- and oxyazo-compounds of the ortho-series. 

 Thus the azo-/3-naphthol colouring-matters, the chrysoidines, 

 &c, may all be formulated on the types 



N N 



X"< | >N . Y X"< | >N . Y 

 N 



H' X H H 



or, in accordance with the ketonic quinone constitutional 

 formula, 



X« N.Y X« /N.Y 



H 7 X H H 



Whether these formula? are accepted or not, the present 

 discussion may serve to indicate the possibility of the existence 

 of tetravalent oxygen in organic compounds, a possibility for 

 which chemists have already been prepared from the inorganic 

 side of their science. It remains to submit these views more 

 fully to the test of experiment, and investigations in the direc- 

 tion indicated have for some time been in progress. I may 

 point out, in conclusion, that the question is not without prac- 

 tical interest in addition to its scientific importance, since the 

 majority of the azo-dves now so largely used in the tinctorial 

 industries belong to the /3-series of naphthalene azo-derivatives. 



Phil. Mag. S. 5. Vol. 26. No. 162. Nov. 1888. 2 F 



