prepared from 3,4-dialkoxyphenylbromides 2. Complexation with metal salts MX (M = Na, Cs) afforded the corresponding derivatives MX5. The uncomplexed crown ethers 5 h and 5 i, with dodecyloxy and tetradecyloxy side chains, respectively, exhibit liquid crystalline properties. In the series of complexed crown ethers, liquid crystal properties appeared as early as NaI5 f with C9H19 side chains. Whereas the
The synthesis of some aromatic crown ether derivatives and their ion-selective electrode properties
作者:Elżbleta Luboch、Andrzej Cygan、Jan F. lernat
DOI:10.1016/s0040-4020(01)82027-5
日期:1990.1
The synthesis of alkyl, nitro and halogeno derivatives of benzo-15-crown-5, benzo- 18-crown-6 and naphtho-15-crown-5 has been reported. Also some novel ester type bis(crown ether)s have been prepared. Some of the compounds have been characterized as electroactive substances in PVC membrane Ion-selective electrodes.
Synthesis and aggregation behavior of hosts containing phthalocyanine and crown ether subunits
作者:Ot E. Sielcken、Marcus M. Van Tilborg、Maarten F. M. Roks、Ron Hendriks、Wiendelt Drenth、Reoland J. M. Nolte
DOI:10.1021/ja00248a021
日期:1987.7
coordinate to the crowns. Cations with diameters that match the diameters of the crownether rings form 4:4 host-guest complexes with the new hosts. Complexes with 8:4 host-guest stoichiometry are formed when the diameters of the cations exceed that of the crownether rings. Binding free energies of the copper phthalocyanine hosts are presented and compared to those of benzo crownethers. The binding profiles
Unsymmetrical crown ether derivatives 7 and 12 with one lateral o-terphenyl unit bearing different ester substituents were synthesized starting from methoxymethyl (MOM) protected bromobenzenes 3 and 8 by conversion into the respective borolanes 4 and 9, twofold Suzuki coupling with dibromobenzo[15]crown-5, acidic deprotection and finally esterification either with various alkanoic chlorides or gallic acids. Reaction with NaI provided the complexes [NaI·(7a–g)] and [NaI·(12a–d)], respectively. Uncomplexed crown ethers as well as their complexes [NaI·7a–c] and [NaI·12a–d] are non-mesogenic. In the case of [NaI·(7d–g)], however, the complexation induced a mesophase formation. As exemplarily shown for [NaI·7d], different textures were observed upon cooling, a fan-shaped texture, which is typical for a columnar hexagonal mesophase, and a striped fan-shaped texture, indicating a second mesophase Colx at low-temperature. From the SAXS diffraction pattern this mesophase was assigned to be columnar rectangular. For [NaI·7g] a different diffraction pattern was found, from which the low-temperature mesophase might be attributed to a soft crystal or a highly ordered columnar mesophase with orthorhombic symmetry.
Rigid polyalicyclic nanostructures with extended and U-shaped geometry and functionalised with 15-crown-5 rings have been prepared from molrac mono or bisalkenes and new crown ether isobenzofurans; substituents in the 1,3-position of the isobenzofuran are used to modify stereospecifities in the cycloaddition process thereby acting as geometrical control agents in the construction process.