SYNTHESES IN THE CINCHONA SERIES. III. AZO DYES DERIVED FROM HYDROCUPREINE AND HYDROCUPREIDINE
Journal of the American Chemical Society
Compounds of Cupreine, Hydrocupreine and their Methyl and Ethyl Ethers," in which the idea of azo-cinchona compounds is elaborated, although only one of the substances describ6d in the present paper (p-sulfo-phenylazo-hydrocupreine) was studied. The work which we now report has been in progress fpr over two years and represents but a portion of the studies which we are making in the field of the cinchona alkaloids2 Among our objects in studying the azo derivatives of the hydroxy alkaloids was
... oxy alkaloids was the reduction of suitable members to the amino alkaloids, which we now see has also been accomplished by the German workers. As far as 3-aminohydrocupreine is concerned, we, too, prepared this interesting compound almost two years ago, and since our work with it and analogous substances is still in progress, we shall reserve our discussion of the amino alkaloids for a future paper. We have found that hydrocupreine and hydrocupreidine behave in a normal manner as phenolic compounds and yield well-defined azo dyes with diazotized aromatic amines. We have assumed from the first that position 5 (una) in the quinoline nucleus is the place of entranck of the azo group CH N since this is the only availablg position which would satisfy the usual rules of substitution for a 6-hydroxy-quinoline derivative, a conclusion also arrived at by Giemsa and Halberkann. 1 Ber., 52, go6 (1919). 2 For Paper I of this series, see THIS JOURNAL, 41, 818 (19x9).