チヤニン色素合成に関する研究 (第20報)

König型Neocyanine類似トリメチン三核色素の合成

抄録

It was found that the respective application of thionyl chloride to quinaldine ethiodide, lepidine ethiodide, and 2-methylbenzothiazole ethiodide yielded 2-trichloromethylquinoline ethochloride (I), 4-trichloromethylquinoline ethochloride (II), and 2-trichloromethylbenzothiazole ethochloride (III). Reaction of (I) with 2 moles of quinaldine ethiodide in acetic anhydride, in the presence of potassium acetate, yielded 1, 1′, 1″-triethyl-10-(2″-quinolyl)-2, 2′-trimethinequinocyanine diiodide (IV) with λ_max 5850 Å. Similar reactions of (II) and lepidine ethiodide and of (III) and 2-methylbenzothiazole ethiodide respectively yielded 1, 1′, 1″-triethyl-10-(4″-quinolyl)-4, 4′-trimethinequinocyanine diiodide (VI) with λ_max 6700 and 5950 Å and 1, 1′, 1″-triethyl-meso-(2″-benzothiazolyl)-2, 2′-trimethinethiocyanine diiodide (VIII) with λ_max 5450 Å. The reaction of (I) and quinaldine ethiodide in xylene, with cadmium carbonate as the addition agent, gave hydriodide or iodide of (IV) with the same absorption maximum as that of (IV), and the same reaction of (II) and lepidine ethiodide gave the hydriodide or iodide of (VI) with λ_max 7100 and 5950 Å, and of (III) and 2-methylbenzothiazole ethiodide, dihydriodide or diiodide of (VIII) with λ_max 5750 Å, all in comparatively good yield. The dehalogenation of these with ammonia respectively gave (IV), (VI), and (VIII).