Fluorene/fluorenone

S. Panozzo, J.-C. Vial, Y. Kervela, and O. Stephan, Fluorene-fluorenone copolymer stable end efficient yellow-emitting material for electroluminescent devices, J. Appl. Phys., 92 3495-3502, 2002. 

Phthalic anhydride 9-Fluorenol, see Fluorene Fluorenone, see Fluorene... 

Oxidation of alcohols or methylene groups. In the presence of PCC or pyr-idinium fluorochromate (PFC)2 as catalyst, t-BuOOH can oxidize alcohols in good yield. This combination also effects oxidation of a benzylic or a propargylic methylene group to a keto group in moderate yield for example indane — 1-indanone, 46-63% yield fluorene — fluorenone, 53% yield. 

The central ring systems found to yield antiviral compounds have included fluorene (fluorenone), dibenzofuran, dibenzothiophene, fluoranthene, anthraquinone, acenaphthene, xanthene, thioxanthene, phenothiazine, carbazole, phenanthrene and others. The side chains were represented by basic ethers, basic ketones, basic esters plus carboxamides, sulphonamides, alkanols, methylene and others attached to the various ring systems. The amine function was usually substituted to the tertiary amine with various alkyl substituents although a few ring types (e.g., pyrrole or piperidino) were synthesized. 

TCBTs are relatively persistent and non-flammable (and therefore useful in hydraulic oils). Pyrolysis in a closed system for two days in the presence of hydrogen peroxide at 300 °C produced as main components chlorinated benzo-phenones, fluorenes, fluorenones, xanthenes, and xanthones. Polychlorodiben-zofurans (PCDF) and polychlorodibenzo-p-dioxins (PCDD) were formed in much lower concentrations than from PCB product Pyralene T1 under identical conditions [84]. In pyrolysis at 450-700 °C with excess oxygen TCBTs produce more PCDFs and PCDDs. In parallel with the behavior of PCBs, PCDFs are formed in significantly higher amounts than PCDDs from PCBTs [86],... 

Fig. 18 Two fluorene-fluorenone co-oligomers and an additional model compound at an intermediate stage of oxidation...

Fig. 12 Normalized fluorescence emission spectra of PFO (black line), 9-fluorenone (red line) and the fluorene-fluorenone copolymer with 25% 9-fluorenone units (PF/FL0.25) (blue line)...

Fig. 13 Fluorescence emission spectra of fluorene-fluorenone copolymers with different 9-fluorenone fractions...

Time-resolved fluorescence studies of fluorene-fluorenone copolymers in dilute toluene solution, enable us to identify different time regimes in the photoluminescence (PL) decay. Figure 18 shows the results of a maximum entropy method (MEM) analysis of the PL decays of fluorene-fluorenone copolymers [58] collected at the fluorene emission wavelength [66]. The different time regimes of the PL decay are associated with different kinetic species which migrate to the defects, most typically these are the CTS defects... 

To support their argument, Walsh performed liquid phase spectroscopic studies of the solutes and cosolvents in liquid acetone, as an analog to supercritical carbon dioxide, and in liquid hexane, as an analog to supercritical ethane. The spectra from the phenanthrene, fluorene, fluorenone, and dibenzofuran solutes dissolved in acetone with 1 mol% methanol clearly show no complex formation. But the spectra also clearly show that acridine forms a complex with methanol. To interpret the Schmitt and Reid study, Walsh and coworkers used hexane as the liquid analog to supercritical ethane. They found... 

In this experiment, fluorene and fluorenone will be separated by column chromatography using alumina as the adsorbent. Because fluorenone is more polar than fluorene, fluorenone will be absorbed to the alumina more strongly. Fluorene will elute off the column with a nonpolar solvent hexane, whereas fluorenone will not come off until a more polar solvent (30% acetone-70% hexane) is put on the column. The purities of the two separated compounds will be tested by TLC and melting points. 

Fig. 14. Correlation between the retention factors forfluorene (y-axis) and the separation factors for fluorene/fluorenone (x-axis) for details, see text.

Ferroelectric liquid crystals having a heterocyclic pyrimidine, pyrazine, or pyridazine ring have been developed. Phenylpyrimidine systems show a characteristic low rotational viscosity, and fused aromatics, such as fluorene, fluorenone, or naphthalene, have been discussed from the viewpoint of dipole moment, spontaneous polarization, and orientability. 

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