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Fluorenone

About: Fluorenone is a research topic. Over the lifetime, 1067 publications have been published within this topic receiving 17162 citations. The topic is also known as: Diphenylene ketone & 9-Oxofluorene.


Papers
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Journal ArticleDOI
TL;DR: In this article, non-enolizable carbonyl compounds were found to undergo intriguing reaction upon heating with hexamethylphosphoric triamide; benzophenone gave 1,1,2,2-tetraphenylethane and benz-phenone methylimine, while fluorenone afforded 9-methylfluorene, 9-dimethylamin-of-fluorene and fluorene.
Abstract: Non-enolizable carbonyl compounds were found to undergo intriguing reaction upon heating with hexamethylphosphoric triamide; benzophenone gave 1,1,2,2-tetraphenylethane and benzophenone methylimine, while fluorenone afforded 9-methylfluorene, 9-dimethylaminofluorene, and fluorene. In contrast, anthrone, an enolizable compound, was completely recovered unchanged under the the same reaction conditions.

4 citations

Journal ArticleDOI
TL;DR: In this paper, the effect of nitrogen atoms on the triplet excited state reactivity of 1,4-diaza-9-fluorenone (1) and 1, 4-daza- 9-benz[b] (2) in acetonitrile was investigated employing the nanosecond laser flash photolysis technique.
Abstract: The effect of the introduction of nitrogen atoms upon the triplet excited state reactivity of 1,4-diaza-9-fluorenone (1) and 1,4-diaza-9-benz[b]fluorenone (2), in acetonitrile, was investigated employing the nanosecond laser flash photolysis technique. The intersystem crossing quantum yield (Φces) for 1 and 2 was determined using 9-fluorenone as a secondary standard (Φces= 0.48, in acetonitrile) and for both diazafluorenones a value of Φces= 0.28 was found. Quenching rate constants ranged from 8.17x104 L mol-1 s-1 (2-propanol) to 1.02x1010 L mol-1 s-1 (DABCO) for 1,4-diaza-9-fluorenone and from 6.95x105 L mol-1 s-1 (2-propanol) to 5.94x109 L mol-1 s-1 (DABCO) for 1,4-diaza-9-benz[b]fluorenone, depending if the quenching process involves energy, hydrogen or electron transfer. A comparison between quenching rate constants for both diazaflurenones and the parent compound, i.e. 9-fluorenone, a ketone with lowest triple state of ππ* configuration, lead to the conclusion that the reactive triplet excited state for 1,4-diaza-9-fluorenone and 1,4-diaza-9-benz[b]fluorenone has ππ* configuration.

4 citations

Journal ArticleDOI
TL;DR: In this article, photophysical characterization of pure oligo(fluorene)s and of the same oligomers containing just one fluorenone (keto-defect) group is reviewed.
Abstract: Chain length dependence of the photoemission (fluorescence, phosphorescence, delayed fluorescence) and the respective life times of poly conjugated macromolecules is subject of controversy since long. An underlying question concerns coherence and extension/localization of the photoexcited states. Energy transfer within and between macromolecules as well as between sensitizers and macromolecules are relevant processes in systems to be used for displays or solar energy harvesting. In this context our recent work on photophysical characterization of pure oligo(fluorene)s and of the same oligomers containing just one fluorenone (keto-defect) group is reviewed. Energy transfer between poly(fluorene)s and metal porphyrins is also covered. Triplet- triplet-annihilation opens a route to efficient non-coherent energy upconversion at ultralow excitation intensity (ca 1 Wcm -2 ). Light from the red region (635-700 nm) of terrestrial sun-light is converted into the green region with AE > 0.5 eV.

4 citations

Patent
28 Mar 2012
TL;DR: In this paper, a method for the preparation of 9-fluorenone is described. But the method is not suitable for the use of industrial fluorene, benzene series solvent, sodium hydroxide and quaternary ammonium salt, and the solvent is toluene or dimethylbenzene.
Abstract: The invention relates to the technical field of production of an aromatic compound 9-fluorenone, in particular to a preparation method of the 9-fluorenone. The preparation method includes the steps as follows: 1) taking industrial fluorene, benzene series solvent, sodium hydroxide and quaternary ammonium salt, and adding the four components in a four-mouth bottle; 2) stirring the mixture in normal pressure, increasing the temperature to above 90 DEG C, reacting, and introducing air for oxidization; 3) conducting reduced-pressure distillation and allowing concentrate to crystallize, thus obtaining yellow fluorenone crystals; and 4) washing the fluorenone crystals for one time and then drying the fluorenone crystals, thus obtaining the 9-fluorenone product. The benzene series solvent is toluene or dimethylbenzene. Compared with the prior art, the preparation method has the benefits as follows: 1) the reaction temperature is low, the operation is simple and convenient and the reaction conditions are moderate; 2) the cheap sodium hydroxide is taken as a catalyst, so the cost is low; 3) the benzene series solvent can be recycled by reduced-pressure distillation, washing water is little in quantity, treatment is easy and pollution to environment is small; and 4) the gas chromatographic purity of the product is higher than 99.2%, the yield is higher than 86.7% and the production requirements are met.

4 citations

Journal ArticleDOI
TL;DR: In this paper, the condensation of some thienyl carbonyl compounds with dimethyl methylsuccinate in presence of potassium t-butoxide or sodium hydride gave predominantly the (E)-half-esters11a-d, which were cyclised to benzothiophene derivatives 2a−d.
Abstract: The condensation of some thienyl carbonyl compounds with dimethyl methylsuccinate in presence of potassium t-butoxide or sodium hydride gave predominantly the (E)-half-esters11a–d, which were cyclised to benzothiophene derivatives 2a–d. The (E)-dibasic acids 6a–d were converted to the corresponding anhydrides 7a–d, which upon methanolysis produced the isomeric half-esters 8a–d. Treatment of 6d with concentrated sulphuric acid gave the cyclic ketonic lactone 9 together with the fluorenone derivative 10.

4 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202311
202221
202124
202026
201928
201822