1956 年 76 巻 6 号 p. 729-732
Mercuration of 5-nitrosalicylic acid (range of color change, pH 3-4.4) and 3, 5-dinitrosalicylic acid with mercury acetate, with heating, results in decarboxylation and the former gives the 2, 6-dimercuri compound of 4-nitrophenol at pH 2.8-7, while the latter forms the 6-mercuri compound of 2, 4-dinitrophenol at pH 3.2-7, both resisting ring mercurization in the alkaline side. The mercuration of 5-nitrosalicylic acid at room temperature results in the formation of a mercury salt (formula I) in the acid range, and an intramolecular mercury comlex, assumed to take the structure shown (formula II), in the alkaline range.
From the results of experiments carried out to date, the nitrophenols and allied compounds with the hydroxyl and nitro or carboxyl group in the ortho-positions are liable to form a mercury complex in a pH range where such compounds take the aci form and this is assumed to be due to the fact that such intramolecular complexes take a stable six-membered ring structure.
Mercuration of 5-nitro-8-hydroxyquinoline (range of color change, pH 3-5.2) at pH 3 and 5.2 afforded a compound assumed to be an intramolecular mercury complex, whose analytical values suggested it to be of structure shown by formula (IV) or (V). The same reaction at pH 7 resulted in the recovery of a majority of the starting materials, with a small amount of the 7-mercuri compound (VI), while mercury compound was not obtained at all at pH 9.