{"id":{"repo_id":"whiterose","oai_identifier":"oai:etheses.whiterose.ac.uk:824"},"canonical_url":"https://search.dev.ndltd.org/etd/whiterose/oai:etheses.whiterose.ac.uk:824","repository":{"repo_id":"whiterose","name":"White Rose University Consortium","base_url":"https://etheses.whiterose.ac.uk/cgi/oai2"},"display":{"title":"Hydrogen Bonded Liquid Crystals from Fluorophenols and Alkoxystilbazoles","abstract":"Hydrogen-bonded complexes between 4-alkoxy-4’-stilbazoles and phenols with different degrees of fluorine substitution were prepared. In contrast to the components, the complexes were observed to exhibit nematic and smectic A phases by polarised optical microscopy, and nematic tendency was found to decrease with increasing alkoxy chain length. A correlation between mesophase stability and the fluorine substitution positions for a given number of fluorine substituents in the phenol was also observed. The mesomorphism of the fluorophenol complexes prepared are compared with similar complexes formed between stilbazoles and 2-, 3- and 4-cyanophenol, as well as between stilbazoles and 3- and 4-nitrophenol. Nine X-ray crystallographic structures of the 4-octyoxy-4’-stilbazole complexed with fluorophenols were also obtained. Eight of the complexes crystallised in the space group, with a back-to-back dimer motif, while the complex of 4-fluorophenol crystallised in the Pbca space group and formed head-to-tail, zig-zagged chains. A linear relationship between the N•••H separation and the pKa value of the corresponding fluorophenol was discovered. Comparisons are made with the analogous halogen-bonded 4-(N,N-dimethylamino)pyridine and iodofluorobenzene complexes, in addition to with the crystal packing of the pure fluorophenols.","abstract_html":"Hydrogen-bonded complexes between 4-alkoxy-4’-stilbazoles and phenols with different degrees of fluorine substitution were prepared. In contrast to the components, the complexes were observed to exhibit nematic and smectic A phases by polarised optical microscopy, and nematic tendency was found to decrease with increasing alkoxy chain length. A correlation between mesophase stability and the fluorine substitution positions for a given number of fluorine substituents in the phenol was also observed. The mesomorphism of the fluorophenol complexes prepared are compared with similar complexes formed between stilbazoles and 2-, 3- and 4-cyanophenol, as well as between stilbazoles and 3- and 4-nitrophenol. Nine X-ray crystallographic structures of the 4-octyoxy-4’-stilbazole complexed with fluorophenols were also obtained. Eight of the complexes crystallised in the space group, with a back-to-back dimer motif, while the complex of 4-fluorophenol crystallised in the Pbca space group and formed head-to-tail, zig-zagged chains. A linear relationship between the N•••H separation and the pKa value of the corresponding fluorophenol was discovered. Comparisons are made with the analogous halogen-bonded 4-(N,N-dimethylamino)pyridine and iodofluorobenzene complexes, in addition to with the crystal packing of the pure fluorophenols.","abstract_has_math":false,"creators":["Wong, Joanna PW"],"institution":"University of York","degree_name":"M.Sc by research","degree_level":"masters","degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Bruce, Duncan","Saez, Isabel"],"committee_chairs":[],"committee_members":[],"year":2009,"date_issued":"2009-12","date_published":"2009-12","updated_at":"2026-07-24T06:03:42Z","subjects":[],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":null,"outbound_label":null,"outbound_source":null},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Bruce, Duncan","Saez, Isabel"]},{"key":"dc:creator","label":"Author","values":["Wong, Joanna PW"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2009-12"]},{"key":"dc:date.issued","label":"Date","values":["2009-12"]},{"key":"dc:publisher.commercial","label":"Dc Publisher Commercial","values":["University of York"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["Chemistry (York)"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of York"]},{"key":"dc:relation.isreferencedby","label":"Dc Relation Isreferencedby","values":["https://etheses.whiterose.ac.uk/id/eprint/824/"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["masters"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["M.Sc by research"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://etheses.whiterose.ac.uk/id/eprint/824/1/Joanna%27s_Thesis_-_Final.pdf"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Hydrogen-bonded complexes between 4-alkoxy-4’-stilbazoles and phenols with different degrees of fluorine substitution were prepared. In contrast to the components, the complexes were observed to exhibit nematic and smectic A phases by polarised optical microscopy, and nematic tendency was found to decrease with increasing alkoxy chain length. A correlation between mesophase stability and the fluorine substitution positions for a given number of fluorine substituents in the phenol was also observed. The mesomorphism of the fluorophenol complexes prepared are compared with similar complexes formed between stilbazoles and 2-, 3- and 4-cyanophenol, as well as between stilbazoles and 3- and 4-nitrophenol. Nine X-ray crystallographic structures of the 4-octyoxy-4’-stilbazole complexed with fluorophenols were also obtained. Eight of the complexes crystallised in the space group, with a back-to-back dimer motif, while the complex of 4-fluorophenol crystallised in the Pbca space group and formed head-to-tail, zig-zagged chains. A linear relationship between the N•••H separation and the pKa value of the corresponding fluorophenol was discovered. Comparisons are made with the analogous halogen-bonded 4-(N,N-dimethylamino)pyridine and iodofluorobenzene complexes, in addition to with the crystal packing of the pure fluorophenols."]},{"key":"dc:format","label":"Dc Format","values":["other"]},{"key":"dc:title","label":"Title","values":["Hydrogen Bonded Liquid Crystals from Fluorophenols and Alkoxystilbazoles"]}]}],"canonical_facts":{"dc:contributor.advisor":["Bruce, Duncan","Saez, Isabel"],"dc:creator":["Wong, Joanna PW"],"dc:date":["2009-12"],"dc:date.issued":["2009-12"],"dc:description.abstract":["Hydrogen-bonded complexes between 4-alkoxy-4’-stilbazoles and phenols with different degrees of fluorine substitution were prepared. In contrast to the components, the complexes were observed to exhibit nematic and smectic A phases by polarised optical microscopy, and nematic tendency was found to decrease with increasing alkoxy chain length. A correlation between mesophase stability and the fluorine substitution positions for a given number of fluorine substituents in the phenol was also observed. The mesomorphism of the fluorophenol complexes prepared are compared with similar complexes formed between stilbazoles and 2-, 3- and 4-cyanophenol, as well as between stilbazoles and 3- and 4-nitrophenol. Nine X-ray crystallographic structures of the 4-octyoxy-4’-stilbazole complexed with fluorophenols were also obtained. Eight of the complexes crystallised in the space group, with a back-to-back dimer motif, while the complex of 4-fluorophenol crystallised in the Pbca space group and formed head-to-tail, zig-zagged chains. A linear relationship between the N•••H separation and the pKa value of the corresponding fluorophenol was discovered. Comparisons are made with the analogous halogen-bonded 4-(N,N-dimethylamino)pyridine and iodofluorobenzene complexes, in addition to with the crystal packing of the pure fluorophenols."],"dc:format":["other"],"dc:identifier.uri":["https://etheses.whiterose.ac.uk/id/eprint/824/1/Joanna%27s_Thesis_-_Final.pdf"],"dc:publisher.commercial":["University of York"],"dc:publisher.department":["Chemistry (York)"],"dc:publisher.institution":["University of York"],"dc:relation.isreferencedby":["https://etheses.whiterose.ac.uk/id/eprint/824/"],"dc:title":["Hydrogen Bonded Liquid Crystals from Fluorophenols and Alkoxystilbazoles"],"dc:type":["Thesis"],"dc:type.qualificationlevel":["masters"],"dc:type.qualificationname":["M.Sc by research"]},"updated_at":"2026-07-24T06:03:42Z"}