Synthesis and Structural Analysis of Some New Sulfanyl Amino 1,4-Naphthoquinone Derivatives

Abstract

In this study, some new sulfanyl substituted amino 1,4-naphthoquinone derivatives which possess two electron donating groups in the amino fragment were synthesized and their structures were analyzed by spectroscopic techniques. First, 2-chloro-3-[(2,4-dimethoxy phenyl)amino]naphthalene-1,4-dione (3a) and 2-chloro-3-[(3,5-dimethoxy phenyl)amino]naphthalene-1,4-dione (3b) were obtained from the reactions of dichloro 1,4-naphthoquinone (1) with 2,4-dimethoxy phenyl amine and 3,5-dimethoxy phenyl amine. Then the compounds 3a,b were reacted with aliphatic nucleophiles; ethyl-, propyl- and pentyl mercaptan. S-Nucleophiles attacked to the carbon atom of 1,4-naphthoquinone core and displaced with the chlorine atom to create target molecules; 2-aryl amino-3-(ethyl thio)naphthalene-1,4-dione (5a,b), 2-aryl amino-3-(propyl thio)naphthalene-1,4-dione (5c,d), 2-aryl amino-3-(pentyl thio)naphthalene-1,4-dione (5e,f) derivatives. The structures of synthesized compounds were proved by utilizing 1D and 2D NMR techniques and also mass spectra and FTIR data.