Synthesis of N-(1-((1H-perimidin-2-yl)amino)-2,2,2-trichloroethyl)carboxamides based on N-(2,2,2-trichloro-1-isothiocyanatoethyl)carboxamides

Here we report the development of a concise and efficient synthetic protocol for the preparation of 1H-perimidin-2-amine derivatives that contain an N-(2,2,2-trichloroethyl)carboxamide substituent near the amino group. These compounds’ synthesis method is based on the interaction of naphthalene-1,8-diamine with N-(2,2,2-trichloro-1-isothiocyanatoethyl)carboxamides under reflux in acetonitrile medium for 15 minutes. This transformation is likely to pass through the stage of formation of the intermediate thiourea, which further eliminates hydrogen sulfide, which is accompanied by the closure of the perimidine cycle. Using the developed protocol, we synthesized nine new 1H-perimidin-2-amine derivatives. The yield of synthesized compounds was 67-82%. IR,¹H NMR,¹³C NMR, ¹H-¹H COSY, ¹H-¹³C HSQC, and ¹H-¹³C HMBC spectroscopy data proved their structures.