Abstract:

Naphtholic naphthalene sulfonate containing tertiary amine group and its derivatives can be used to synthesize universal dyes, cationic dyes and acid dyes. According to the literatures, it can be obtained by condensation of 7-acetamide-4-hydroxy-2-naphthalenesulfonyl chloride with N, N-dimethylethylenediamine, followed by esterfication of the hydroxyl group using excessive sulfonyl chloride in -N, N-dimethylformamide (DMF) in the presence of pyridine. In this paper, an inexpensive synthesis method for naphtholic naphthalene sulfonate is described, the required operations in which are also more convenient as compared with the former methods. Naphtholic naphthalene sulfonate were prepared by treating-N, N-dimethylethylenediamine with 7-acetamide-4-hydroxy-2-naphthalenesulfonyl chloride in acetonitrile in the presence of K₂CO₃. The structure of the compound was elucidated by 1D ¹H and ¹³C NMR and two-dimensional NMR spectroscopy including gCOSY, TOCSY, gHMBC and gHSQC. The complete ¹H and ¹³Cchemical shifts and the ¹H-¹H coupling constants were obtained.

Key words: Naphtholic naphthalene sulfonate, Two-dimensional NMR spectroscopy, chemical shift assignment