title: Synthesis and Characterization of Macrocyclic Polyether N,N'-Diallyl-7,16-diaza-1,4,10,13-tetraoxa-dibenzo-18-crown-6.
abstract: In this study an efficient and direct production procedure for a macrocyclic polyether N,N'-diallyl-7,16-diaza-1,4,10,13-tetraoxa-dibenzo-18-crown-6 from the reaction of catechol and N,N-bis(2-chloroethyl)prop-2-en-1-amine in n-butanol in the presence of a strong base is reported. The synthesis involves a two-step addition of sodium hydroxide to enhance the cyclization process, and at the end of the reaction, the reaction mixture is neutralized and the solvent replaced with water in-situ through distillation to afford a relatively pure precipitate that is easily recrystallized from acetone. The yield of the macrocycle was 36%-45% and could be scaled-up to one-mole quantities. The structure and purity of this compound was verified on the basis of elemental analysis, IR, UV-Vis, ¹H-, (13)C-NMR, 2D-NMR, mass spectroscopy, and thermal analysis. The white crystalline compound has a sharp melting point of 124 °C and a crystallization temperature of 81.4 °C determined by differential scanning calorimetry. Our motivation behind the synthesis of the bibracchial lariat azacrown polyether ligand was to examine its possible applications in ion-selective polymer-supported materials.
authors: Freiburg Materials Research Center, Stefan-Meier-Straße 21, 79104 Freiburg, Germany. ratumo.toeri@biomat.uni-freiburg.de.|Chair of Forest Biomaterials, University of Freiburg, Werthmanstr. 6, 79085 Freiburg, Germany. ratumo.toeri@biomat.uni-freiburg.de.
authors: Julius
authors: J
authors: Toeri
authors: Freiburg Materials Research Center, Stefan-Meier-Straße 21, 79104 Freiburg, Germany. marie-pierre.laborie@biomat.uni-freiburg.de.|Chair of Forest Biomaterials, University of Freiburg, Werthmanstr. 6, 79085 Freiburg, Germany. marie-pierre.laborie@biomat.uni-freiburg.de.
authors: Marie-Pierre
authors: MP
authors: Laborie
mesh_terms: D043844:Crown Ethers / Q000138:chemical synthesis* / Q000737:chemistry; D003460:Crystallization; D003500:Cyclization; D044366:Transition Temperature
chemical_list: D043844:Crown Ethers
keywords: 4,16-diaza-18-crown-6; N-substituted azacrown polyether; lariat azacrown ether; molecular recognition; synthesis