Quantivalence of Oxygen. 407 



In the next place Zincke and Lawson * isolated the diazo- 

 salts of benzeneazo-/3-naphthylamine, and showed that these 

 were decomposed quite normally by water into benzeneazo-/3- 

 naphthol. Lastly, the author and F. J. East f showed that 

 para- and meta-nitrobenzene-azo-/3-naphthylamine could be 

 converted by means of nitrous acid in the presence of acetic 

 acid into the corresponding /3-naphthyl-acetates, i. e., 



CioH 

 into 



/N, . C 6 H 4 . N0 2 (p. or m.) 

 6X NH 2 (/3) 



N 2 .C 6 H 4 .N0 2 (p.orm.) 

 6x O.C 2 H 3 0(/3) 



Such facts as these point distinctly to the presence of a 

 diazotizable XH 2 -group; nevertheless the difficulty with which 

 these compounds are diazotized and the instability of the diazo- 

 salts as compared with the a-naphthylamine diazo-derivatives 

 must be allowed due weight as evidence of a different consti- 

 tution, a conclusion which is borne out by the formation of 

 oxidation-products of the azimido-type. 



The evidence with respect to the absence of hydroxyl in the 

 /3-naphtholazo-derivatives has also of late been much weakened, 

 if not altogether destroyed, by the results of Weinberg, Ja- 

 cobson, and others. If the foregoing evidence of the presence 

 of amidogen in the /3-naphthylamine-azo-derivatives is consi- 

 dered conclusive, analogy leads to the conclusion that hydroxyl 

 is present in the p-naphthol derivatives. The two groups of 

 compounds are perfectly analogous and the latter can, as 

 already stated, be obtained directly from the former by the 

 replacement of KH 2 by HO by the diazo-reaction. The 

 presence of a replaceable hydrogen atom in benzeneazo-/3- 

 naphthol is shown by the fact that this compound can be 

 ethylated by sodium ethylate and ethyl iodide J as well as by 

 the tact that the said compound can be acetylated§. The 

 mere fact of a replaceable hydrogen atom being present does 

 not. however, give a decision in favour of either formula; the 

 ethyl-derivative, for example, might be : — 



* Ber. 1887, p. 2896. 

 t Journ. Chem. Soc, Trans. 1888, p. 464. 



X Weinberg, Ber. 1887, p. 3171. A quantity of this ethyl derivative 

 has been placed at the disposal of the author by Dr. Weinberg, and its 



Jiroducts of reduction are being investigated in the laboratory of the 

 unsbury Technical Col!' \ 

 § Meldola and East, loc. eit. p. 4(i»i. 



