{"id":{"repo_id":"aachen","oai_identifier":"oai:publications.rwth-aachen.de:61638"},"canonical_url":"https://search.dev.ndltd.org/etd/aachen/oai:publications.rwth-aachen.de:61638","repository":{"repo_id":"aachen","name":"RWTH Aachen University","base_url":"https://publications.rwth-aachen.de/oai2d"},"display":{"title":"Enantiomerenreine beta-Diketonate für lumineszierende helicat-artige Komplexe","abstract":"The work bases on ß-diketonates which all bear a chiral spacer and the following complexations lead to enantiomerically pure helicates. All ligands were synthesised by a Claisen-type condensation reaction . During the work a huge number of optimisation attempts of the coupling reaction, as well as alternative synthesis routes, like Knoevenagel-, Fries- or Cupratreactions have been carried out. The formation of helicates base on the self-assembling process. Studies with regard to her origin offer the possibility to examine basic processes of the supramoleculare chemistry, like self-organization, noncovalent interactions, templateffects and stereochemistry, thoroughly. This lead again to a better understanding of complicated biological systems which likewise originate from the aggregation of smaller components by noncovalent interactions. Furthermore important knowledge about the \"host-guest-principle\", that plays an essential role in biological systems and processes and was put up by Fischer, can be won. One supposes that the formation of helicates runs off under strict self-organization as we have observed for complexes of iron (III) and gallium (III) with ligands suitable for the formation of helicates. Similar complexations with gallium (III) and inappropriate ligands led not to the generation of helicates, but to a cluster which exists of four dinuclear doublestranded helicale units. These are possible intermediate stages within the formation process of helicates. Beside the ligand structure the metal also plays a determining role as could be pointed out by complexes with nickel (II). According to the stoichiometry the helicat as well as a trinuclear doublestranded complex could be synthesised. Circulardichroism and fluorescence measurements of both complexes confirm the structural differences. The doublestarnded complex is less symmetrical, that result in a more complex CD-spectrum. After irradiation with light of the wavelength 345 nm one receives a fluorescence signal at 445 nm; in contrast to the highly symmetrical triplestranded helicat which shows no fluorescence activity. The most different functions can be introduced to helicates by choice of suitable metals. Special attention is dedicated in the present work to lanthanides. Using trivalent lanthanides lead to luminescent helicate-type complexes which can be exploited to generate OLEDs. Other applications in medical (fluoroimmunoessays, contrast medium) and everyday areas (luminescent tissue) are absolutely conceivable. The ß-diketonate described on top have turned out to be efficient \"antennae\" systems which cause an excellent energy transfer. To examine the influence of the number and the structure of the ligands, double-, triple- and quadrupelstranded europium complexes with different ß diketonate ligands were synthesised. Fluorescence measurements in solid state shows after irradiation with ultraviolet light of the wavelength 340 nm the characteristically emission signal of the 5D0 -> 7F2 transfer in the europium(III) with 610 nm. The fluorescence measurements were carried out at roomtemperature as well as at deep temperatures. The resultant fine splitting of the emission signals give first signs with regard to the symmetry of the complexes and the coordination surrounding of the europium(III). All complexes are less symmetric and only one coordination polyhedron at the europium can be distinguished. However, a statement about the influence of the ligands on the intensity of the luminescence is possible only by determine the quantum yields. These results are not up to the current time yet. Trivalent lanthanide complexes show catalytic activity on account of their Lewis acidity. Therefore the synthesised lanthanide complexes should be used as catalysts in a Diels-Alder reaction. The first attempts showed weak catalytic activity for an europium(III) complex as well as for an ytterbium(III) complex. Furthermore complexes with nickel (II), iron (III) or vanadium (IV) have been synthesised and been examined with regard to their catalytic qualities. The use of enantiomerically pure helicates is especially interesting in view of enantioselective catalysis. Beside catalytic activity the possibility of chiral induction should be studied during the reaction as well. Unfortunately no enantioselectivity could be observed.","abstract_html":"The work bases on ß-diketonates which all bear a chiral spacer and the following complexations lead to enantiomerically pure helicates. All ligands were synthesised by a Claisen-type condensation reaction . During the work a huge number of optimisation attempts of the coupling reaction, as well as alternative synthesis routes, like Knoevenagel-, Fries- or Cupratreactions have been carried out. The formation of helicates base on the self-assembling process. Studies with regard to her origin offer the possibility to examine basic processes of the supramoleculare chemistry, like self-organization, noncovalent interactions, templateffects and stereochemistry, thoroughly. This lead again to a better understanding of complicated biological systems which likewise originate from the aggregation of smaller components by noncovalent interactions. Furthermore important knowledge about the "host-guest-principle", that plays an essential role in biological systems and processes and was put up by Fischer, can be won. One supposes that the formation of helicates runs off under strict self-organization as we have observed for complexes of iron (III) and gallium (III) with ligands suitable for the formation of helicates. Similar complexations with gallium (III) and inappropriate ligands led not to the generation of helicates, but to a cluster which exists of four dinuclear doublestranded helicale units. These are possible intermediate stages within the formation process of helicates. Beside the ligand structure the metal also plays a determining role as could be pointed out by complexes with nickel (II). According to the stoichiometry the helicat as well as a trinuclear doublestranded complex could be synthesised. Circulardichroism and fluorescence measurements of both complexes confirm the structural differences. The doublestarnded complex is less symmetrical, that result in a more complex CD-spectrum. After irradiation with light of the wavelength 345 nm one receives a fluorescence signal at 445 nm; in contrast to the highly symmetrical triplestranded helicat which shows no fluorescence activity. The most different functions can be introduced to helicates by choice of suitable metals. Special attention is dedicated in the present work to lanthanides. Using trivalent lanthanides lead to luminescent helicate-type complexes which can be exploited to generate OLEDs. Other applications in medical (fluoroimmunoessays, contrast medium) and everyday areas (luminescent tissue) are absolutely conceivable. The ß-diketonate described on top have turned out to be efficient "antennae" systems which cause an excellent energy transfer. To examine the influence of the number and the structure of the ligands, double-, triple- and quadrupelstranded europium complexes with different ß diketonate ligands were synthesised. Fluorescence measurements in solid state shows after irradiation with ultraviolet light of the wavelength 340 nm the characteristically emission signal of the 5D0 -> 7F2 transfer in the europium(III) with 610 nm. The fluorescence measurements were carried out at roomtemperature as well as at deep temperatures. The resultant fine splitting of the emission signals give first signs with regard to the symmetry of the complexes and the coordination surrounding of the europium(III). All complexes are less symmetric and only one coordination polyhedron at the europium can be distinguished. However, a statement about the influence of the ligands on the intensity of the luminescence is possible only by determine the quantum yields. These results are not up to the current time yet. Trivalent lanthanide complexes show catalytic activity on account of their Lewis acidity. Therefore the synthesised lanthanide complexes should be used as catalysts in a Diels-Alder reaction. The first attempts showed weak catalytic activity for an europium(III) complex as well as for an ytterbium(III) complex. Furthermore complexes with nickel (II), iron (III) or vanadium (IV) have been synthesised and been examined with regard to their catalytic qualities. The use of enantiomerically pure helicates is especially interesting in view of enantioselective catalysis. Beside catalytic activity the possibility of chiral induction should be studied during the reaction as well. Unfortunately no enantioselectivity could be observed.","abstract_has_math":false,"creators":["Dehn, Sabrina"],"institution":"Publikationsserver der RWTH Aachen University","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Albrecht, Markus"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2007,"date_issued":"2007","date_published":"2007","updated_at":"2026-07-30T19:43:10Z","subjects":["info:eu-repo/classification/ddc/540","Chemie","Supramolekulare Chemie","Helicate","Lanthanoide","Lumineszenz","Selbstorganisation","ß-Diketonate, enantiomerenrein","ß-diketonates","enantiomerically pure"],"languages":["ger"],"rights":["info:eu-repo/semantics/openAccess"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-123279%22"],"render_values":[{"text":"https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-123279%22","href":"https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-123279%22","code":true}]}]},"links":{"outbound_url":"https://publications.rwth-aachen.de/record/61638","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Albrecht, Markus"]},{"key":"dc:creator","label":"Author","values":["Dehn, Sabrina"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:coverage","label":"Dc Coverage","values":["DE"]},{"key":"dc:date","label":"Dc Date","values":["2007"]},{"key":"dc:publisher","label":"Institution","values":["Publikationsserver der RWTH Aachen University"]},{"key":"dc:relation","label":"Dc Relation","values":["info:eu-repo/semantics/altIdentifier/urn/urn:nbn:de:hbz:82-opus-18115"]},{"key":"dc:type","label":"Dc Type","values":["info:eu-repo/semantics/doctoralThesis","info:eu-repo/semantics/publishedVersion"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["info:eu-repo/classification/ddc/540","Chemie","Supramolekulare Chemie","Helicate","Lanthanoide","Lumineszenz","Selbstorganisation","ß-Diketonate, enantiomerenrein","ß-diketonates","enantiomerically pure"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["ger"]},{"key":"dc:rights","label":"Dc Rights","values":["info:eu-repo/semantics/openAccess"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://publications.rwth-aachen.de/record/61638","https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-123279%22"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["The work bases on ß-diketonates which all bear a chiral spacer and the following complexations lead to enantiomerically pure helicates. All ligands were synthesised by a Claisen-type condensation reaction . During the work a huge number of optimisation attempts of the coupling reaction, as well as alternative synthesis routes, like Knoevenagel-, Fries- or Cupratreactions have been carried out. The formation of helicates base on the self-assembling process. Studies with regard to her origin offer the possibility to examine basic processes of the supramoleculare chemistry, like self-organization, noncovalent interactions, templateffects and stereochemistry, thoroughly. This lead again to a better understanding of complicated biological systems which likewise originate from the aggregation of smaller components by noncovalent interactions. Furthermore important knowledge about the \"host-guest-principle\", that plays an essential role in biological systems and processes and was put up by Fischer, can be won. One supposes that the formation of helicates runs off under strict self-organization as we have observed for complexes of iron (III) and gallium (III) with ligands suitable for the formation of helicates. Similar complexations with gallium (III) and inappropriate ligands led not to the generation of helicates, but to a cluster which exists of four dinuclear doublestranded helicale units. These are possible intermediate stages within the formation process of helicates. Beside the ligand structure the metal also plays a determining role as could be pointed out by complexes with nickel (II). According to the stoichiometry the helicat as well as a trinuclear doublestranded complex could be synthesised. Circulardichroism and fluorescence measurements of both complexes confirm the structural differences. The doublestarnded complex is less symmetrical, that result in a more complex CD-spectrum. After irradiation with light of the wavelength 345 nm one receives a fluorescence signal at 445 nm; in contrast to the highly symmetrical triplestranded helicat which shows no fluorescence activity. The most different functions can be introduced to helicates by choice of suitable metals. Special attention is dedicated in the present work to lanthanides. Using trivalent lanthanides lead to luminescent helicate-type complexes which can be exploited to generate OLEDs. Other applications in medical (fluoroimmunoessays, contrast medium) and everyday areas (luminescent tissue) are absolutely conceivable. The ß-diketonate described on top have turned out to be efficient \"antennae\" systems which cause an excellent energy transfer. To examine the influence of the number and the structure of the ligands, double-, triple- and quadrupelstranded europium complexes with different ß diketonate ligands were synthesised. Fluorescence measurements in solid state shows after irradiation with ultraviolet light of the wavelength 340 nm the characteristically emission signal of the 5D0 -> 7F2 transfer in the europium(III) with 610 nm. The fluorescence measurements were carried out at roomtemperature as well as at deep temperatures. The resultant fine splitting of the emission signals give first signs with regard to the symmetry of the complexes and the coordination surrounding of the europium(III). All complexes are less symmetric and only one coordination polyhedron at the europium can be distinguished. However, a statement about the influence of the ligands on the intensity of the luminescence is possible only by determine the quantum yields. These results are not up to the current time yet. Trivalent lanthanide complexes show catalytic activity on account of their Lewis acidity. Therefore the synthesised lanthanide complexes should be used as catalysts in a Diels-Alder reaction. The first attempts showed weak catalytic activity for an europium(III) complex as well as for an ytterbium(III) complex. Furthermore complexes with nickel (II), iron (III) or vanadium (IV) have been synthesised and been examined with regard to their catalytic qualities. The use of enantiomerically pure helicates is especially interesting in view of enantioselective catalysis. Beside catalytic activity the possibility of chiral induction should be studied during the reaction as well. Unfortunately no enantioselectivity could be observed."]},{"key":"dc:source","label":"Dc Source","values":["Aachen : Publikationsserver der RWTH Aachen University 204 S. : Ill., graph. Darst. (2007). = Aachen, Techn. Hochsch., Diss., 2007"]},{"key":"dc:title","label":"Title","values":["Enantiomerenreine beta-Diketonate für lumineszierende helicat-artige Komplexe"]}]}],"canonical_facts":{"dc:contributor":["Albrecht, Markus"],"dc:coverage":["DE"],"dc:creator":["Dehn, Sabrina"],"dc:date":["2007"],"dc:description":["The work bases on ß-diketonates which all bear a chiral spacer and the following complexations lead to enantiomerically pure helicates. All ligands were synthesised by a Claisen-type condensation reaction . During the work a huge number of optimisation attempts of the coupling reaction, as well as alternative synthesis routes, like Knoevenagel-, Fries- or Cupratreactions have been carried out. The formation of helicates base on the self-assembling process. Studies with regard to her origin offer the possibility to examine basic processes of the supramoleculare chemistry, like self-organization, noncovalent interactions, templateffects and stereochemistry, thoroughly. This lead again to a better understanding of complicated biological systems which likewise originate from the aggregation of smaller components by noncovalent interactions. Furthermore important knowledge about the \"host-guest-principle\", that plays an essential role in biological systems and processes and was put up by Fischer, can be won. One supposes that the formation of helicates runs off under strict self-organization as we have observed for complexes of iron (III) and gallium (III) with ligands suitable for the formation of helicates. Similar complexations with gallium (III) and inappropriate ligands led not to the generation of helicates, but to a cluster which exists of four dinuclear doublestranded helicale units. These are possible intermediate stages within the formation process of helicates. Beside the ligand structure the metal also plays a determining role as could be pointed out by complexes with nickel (II). According to the stoichiometry the helicat as well as a trinuclear doublestranded complex could be synthesised. Circulardichroism and fluorescence measurements of both complexes confirm the structural differences. The doublestarnded complex is less symmetrical, that result in a more complex CD-spectrum. After irradiation with light of the wavelength 345 nm one receives a fluorescence signal at 445 nm; in contrast to the highly symmetrical triplestranded helicat which shows no fluorescence activity. The most different functions can be introduced to helicates by choice of suitable metals. Special attention is dedicated in the present work to lanthanides. Using trivalent lanthanides lead to luminescent helicate-type complexes which can be exploited to generate OLEDs. Other applications in medical (fluoroimmunoessays, contrast medium) and everyday areas (luminescent tissue) are absolutely conceivable. The ß-diketonate described on top have turned out to be efficient \"antennae\" systems which cause an excellent energy transfer. To examine the influence of the number and the structure of the ligands, double-, triple- and quadrupelstranded europium complexes with different ß diketonate ligands were synthesised. Fluorescence measurements in solid state shows after irradiation with ultraviolet light of the wavelength 340 nm the characteristically emission signal of the 5D0 -> 7F2 transfer in the europium(III) with 610 nm. The fluorescence measurements were carried out at roomtemperature as well as at deep temperatures. The resultant fine splitting of the emission signals give first signs with regard to the symmetry of the complexes and the coordination surrounding of the europium(III). All complexes are less symmetric and only one coordination polyhedron at the europium can be distinguished. However, a statement about the influence of the ligands on the intensity of the luminescence is possible only by determine the quantum yields. These results are not up to the current time yet. Trivalent lanthanide complexes show catalytic activity on account of their Lewis acidity. Therefore the synthesised lanthanide complexes should be used as catalysts in a Diels-Alder reaction. The first attempts showed weak catalytic activity for an europium(III) complex as well as for an ytterbium(III) complex. Furthermore complexes with nickel (II), iron (III) or vanadium (IV) have been synthesised and been examined with regard to their catalytic qualities. The use of enantiomerically pure helicates is especially interesting in view of enantioselective catalysis. Beside catalytic activity the possibility of chiral induction should be studied during the reaction as well. Unfortunately no enantioselectivity could be observed."],"dc:identifier":["https://publications.rwth-aachen.de/record/61638","https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-123279%22"],"dc:language":["ger"],"dc:publisher":["Publikationsserver der RWTH Aachen University"],"dc:relation":["info:eu-repo/semantics/altIdentifier/urn/urn:nbn:de:hbz:82-opus-18115"],"dc:rights":["info:eu-repo/semantics/openAccess"],"dc:source":["Aachen : Publikationsserver der RWTH Aachen University 204 S. : Ill., graph. Darst. (2007). = Aachen, Techn. Hochsch., Diss., 2007"],"dc:subject":["info:eu-repo/classification/ddc/540","Chemie","Supramolekulare Chemie","Helicate","Lanthanoide","Lumineszenz","Selbstorganisation","ß-Diketonate, enantiomerenrein","ß-diketonates","enantiomerically pure"],"dc:title":["Enantiomerenreine beta-Diketonate für lumineszierende helicat-artige Komplexe"],"dc:type":["info:eu-repo/semantics/doctoralThesis","info:eu-repo/semantics/publishedVersion"]},"updated_at":"2026-07-30T19:43:10Z"}