title: Resorcarenes in the boat conformation as building blocks for hydrogen-bonded assemblies including two ammonium cations.
abstract: Crystal structures are reported for various co-crystals of rccc-resorcarenes with triethylammonium chloride. Usually, two molecules of a C2v-symmetric tetraester 2 in the boat conformation are linked through four hydrogen-bonded chloride anions to give dimeric assemblies. Two of the chloride anions may be replaced by four hydrogen-bonded ethanol molecules in an otherwise similar structure. These assemblies, which consist of six or eight components, posses voluminous, negatively charged chambers in which two triethylammionium cations, 3+, are included as guests by strong electrostatic and hydrogen-bonding interactions. The host-guest N-H...Cl hydrogen bonds were clearly detected at 173 K. These are the first examples of hydrogen-bonded, solid-state capsules trapping two ions of the same charge in close proximity. In the 1:2 complex with 3+ Cl-, the molecule of the parent resorcarene 1 also adopts a boat conformation whose cavity is considerably extended by four hydrogen-bonded chloride anions. The pocket formed in this way again includes two 3+ ions as a result of electrostatic and hydrogen bonding host-guest interactions. All these structures show that the boat conformers of resorcarenes can be used as a novel motif for the construction of hydrogen-bonded assemblies capable of molecular inclusion and encapsulation.
authors.affiliation: Department of Chemistry, University of Jyväskylä, Finland. shivan@jyu.fi
authors.forename: A
authors.initials: A
authors.lastname: Shivanyuk
authors.forename: E F
authors.initials: EF
authors.lastname: Paulus
authors.forename: K
authors.initials: K
authors.lastname: Rissanen
authors.forename: E
authors.initials: E
authors.lastname: Kolehmainen
authors.forename: V
authors.initials: V
authors.lastname: Böhmer