Fine Synthesis Of Calixarene Oligomeric Sulfonates

Calixarenes were synthetic macrocycles derived from the condensation of p-substituted phenyl and formaldehyde. Calixarenes taken as the third generation of supramolecular compounds had received particular interest of numerous chemists in the past two decades, and all kinds of calixarene derivatives might be obtained considering the molecular"platform"based calixarene skeletons. In this paper, a series of water-soluble calix[4]arene alkyl-ether sulfonates were synthesized from p-tert-butylphenol, formaldehyde, phenol, sulfuric acid, and bromoalkane via five-step process, involving polycondensation reaction, anti-alkylation, sulfonation and etherification reaction. The affection of the reaction conditions were investigated by mang experiments, and the optimum conditions of the reaction were obtained. The calix[4]arene alkyl-ether sulfonates were qualitatively identified to be anionic surfactants by dye method. The structures of intermediates and final products were confirmed to be correct by IR and 1H NMR.The surface tensions of dilute aqueous solutions of products were measured at 25℃by drop-volume method. The surface tensions of 1-C₄, 1-C₆, 1-C₈, 1-C₁₀ were 32.06 mN/m, 34.96 mN/m, 42.35 mN/m, 45.35 mN/m; the cmc of the aboved oligomeric surfactants were 1.26×10^-3mol/L, 0.32×10^-3mol/L, 1.78×10^-3mol/L, 1.2×10^-3mol/L. The interfacial performance of the surfactants were also investigated, and the nmin of 1-C₄, 1-C₆, 1-C₈, 1-C₁₀ were measured.