X-ray Structure and Alkyl Ammonium Recognition of Quadruply Bridged Calix[6]arene:A Selective Inclusion of Primary Alkyl Ammonium with Calix[6]arene

摘要: Numerous attempts have been made to design new host systems which can selectively interact the target guest and perform intriguing molecular recognition processes. The selective of many important biogenic amines is one fundamental research interests in field biomimetic chemistry. Particularly, binding organic ammonium guests attracts an interest due application biological systems, results developing sophisticated systems. Calixarenes present attractive possibilities hostguest chemistry as frameworks for preparation conformationally preorganized polyfunctional derivatives, whose convergent ligating groups act cooperatively bind ions or neutral molecules. Especially, architecture calixarenes such that they also possess hydrophobic cavities generated by aromatic walls phenol residues, are potentially useful inclusion alkyl ions. Whereas calix[4]arene cavity cone conformation too narrow accommodate even small amine salts, calix[6]arene large enough include medium-sized parent calix[6]arenes, however, mobile. most effective approach make them immobile build a bridge at lower upper rim. Ever since Gutsche created rim-bridged 1993, several rim-multibridged calix[6]arenes reported. Also calix[6](aza)cryptand has tripodal poly-aza cap on rim efficient was reported U. Darbost et al. quadruply bridged had our group, known having well-defined capable incorporating various cations. Here we report X-ray structure (3) properties alkylammonium picrates H NMR analysis. Binding were analyzed from NOE study.