Calix[6] pyrroles capped with 1,3,5-trisubstituted benzene

One side of the calix[6] pyrrole, capped with 1,3,5-trisubstituted benzene, have been synthesized for the first time and fully characterized. The synthesis of the target systems were accomplished by acid-catalyzed cyclization of ester/ether-functionalized tripodal dipyrromethanes. The solution state binding studies of the capped calix[6] pyrroles revealed a slow complexation/decomplexation kinetics for fluoride anion and chloride anion. The results indicated that fluoride anion binds inside the cavity with 1/1 binding stoichiometry. On the other hand, only four pyrrolic N-Hs participate in chloride anion binding.