The synthesis of novel chromotropic dyes with surface activity and a regulable color transition point derived from phenolsul-fonphthalein

Abstract

Three novel compounds called 3’,3”-dodecyl-2-sulfonyl phthalein (DSP), 3’, 3”-myristyl-2-sulfonyl phthalein (MSP) and 3’,3”-dodecyl-5’,5’’-nitro-2-sulfonyl phthalein (DNSP) were synthesized to play as functional dyes in both chemical and biological areas. The as-synthesized chromotropic dyes were characterized by NMR, elemental analysis and pH value tester also the allochroic behaviors and surface activity of the new compounds were tested and performed in details mainly with the optical contact angle measurement and UV-Vis spectrophotometer. The introduction of the long chain alkyl groups into the skeleton is aiming to increase the surface activity of those dyes while that of the nitro group was focused on the regulation of the color transition point (CTP). The results indicated that the target dyes showed satisfying properties in not only the chromogenic performance but also the surface activity. Therefore, it may be an effective and durable functional dye with further potential applications in the field of pH sensors, probe and coating materials.