Novel 1,2-3,4-bridged and 1,3-bridged calix[4]arene based on large s-triazine conjugate systems: Synthesis and complexation for dyes

摘要

Two novel 1,2-3,4-bridged and 1,3-bridged calix[4]arenes 6 and 9 based on large s-triazine conjugate systems were designed and synthesized in high yields. The liquid-liquid extraction experiment showed that they possessed excellent extraction abilities towards one cationic and three anionic dyes [Orange I (OI), Methylene blue (MB), Neutral red (NR), Brilliant green (BG)]. The highest extraction percentage of compound 9 was 91.2% for BG. The complexation UV-Vis spectra of compounds 6 and 9 with four dyes indicated the existence of complexation action between hosts and guests with 1:1 ratio of complexation in DMSO solution. The association constants suggested that the 1,2-3,4-bridging structure was more favorable for producing excellent complexation abilities than 1,3-bridging structure. The association constant of compound 9 with BG was as high as 4.5 × 10~6 M~(-1).