%0 Journal Article %T Novel Luminescent Diazafluorenone Liquid Crystals %+ Universität Stuttgart [Stuttgart] %+ Institut des Sciences Chimiques de Rennes (ISCR) %A Bader, Korinna %A Baro, Angelika %A Ehni, Philipp %A Frey, Wolfgang %A Guendemir, Rafet %A Laschat, Sabine %A Molard, Yann %Z Deutsche Forschungsgemeinschaft [HBFG INST 41/815-1 FUGG] %Z Deutsche Akademische Austauschdienst (PPP Procope program PLISE) %Z Fonds der Chemischen Industrie %Z Bundesministerium fiir Bildung und Forschung [01 R105177] %Z Carl-Schneider Stiftung Aalen %Z Ministerium fiir Wissenschaft, Forschung und Kunst des Landes Baden-Wurttemberg %< avec comité de lecture %@ 1528-7483 %J Crystal Growth & Design %I American Chemical Society %V 19 %N 8 %P 4436-4452 %8 2019 %D 2019 %R 10.1021/acs.cgd.9b00211 %K fluorenone %K luminescence %K crystal structure %K mesophases %K nematic %K smectic %K columnar %K X-ray diffraction %Z Chemical Sciences/Organic chemistry %Z Chemical Sciences/CristallographyJournal articles %X In this work, the synthesis, X-ray crystal structure analysis, studies on meso-morphism and luminescence spectroscopy of 2,7-diphenyl-4,5-diazafluorenones carrying 2, 4 or 6 peripheral alkoxy side chains of different lengths in the mesogenic unit are reported. The latter was attached to starting 2,7-dibromo-4,5-diazafluoren-9-one via Suzuki cross coupling of the respective 2-(alkoxyphenyl)-tetramethyl-1,2,3-borolane. The liquid crystalline properties were found to depend on both the number of side chains and their lengths. Derivatives with two short alkoxy chains (C6-C8) in the periphery formed nematic (N) and smectic C (SmC) mesophases while for the higher homologues only SmC mesophases were observed. Compounds carrying six alkoxy side chains with a minimum length of C8 assembled into columnar hexagonal phases. Homologues with C14 and C16 chain length displayed additionally two columnar rectangular mesophases. Four peripheral alkoxy chains, however, led to the loss of mesomorphism. Crystal structure data of a series of rod-shaped diazafluorenones helped to rationalize their liquid crystalline self-assembly and to understand geometry and thermal stability. Temperature-dependent luminescence spectra of diazafluorenone with two C12 chains revealed aggregation-induced emission (AIE) depending on the supramolecular order of the bulk phase. These studies suggested that AIE requires a lower degree of aggregation as compared to mesophase formation. %G English %2 https://univ-rennes.hal.science/hal-02278403/document %2 https://univ-rennes.hal.science/hal-02278403/file/Bader%20et%20al-2019-Novel%20Luminescent%20Diazafluorenone%20Liquid%20Crystals.pdf %L hal-02278403 %U https://univ-rennes.hal.science/hal-02278403 %~ UNIV-RENNES1 %~ CNRS %~ INSA-RENNES %~ ENSC-RENNES %~ ISCR %~ ISCR-CSM %~ STATS-UR1 %~ UR1-SPM %~ INC-CNRS %~ UR1-UFR-SPM %~ UR1-HAL %~ UR1-SDLM %~ TEST-UR-CSS %~ UNIV-RENNES %~ INSA-GROUPE %~ TEST-HALCNRS %~ UR1-MMS %~ TEST2-HALCNRS %~ TEST3-HALCNRS