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.

Complexes containing redox-active fluorenone-based ligands linked to redox-active tris(pyrazolyl)boratomolybdenum fragments: assignment of ligand-centred and metal-centred redox processes by EPR and UV/VIS/NIR spectroelectrochemistry †

Abstract: The dinuclear complex [{Mo(TpMe,Me)(NO)Cl}2(µ-L2)] 2 [L2 is the new bridging ligand 2,7-bis{2-(4-pyridyl)ethen-1-yl}fluorenone] contains two redox-active molybdenum(I) centres linked by a bridging ligand which is itself redox-active by virtue of the fluorenone spacer unit. The complex undergoes four one-electron reductions of which two are metal-centred Mo(0)/Mo(I) couples and two are reductions of the fluorenone unit. Also studied were the mononuclear analogue [Mo(TpMe,Me)(NO)Cl(L1)] [L1 is 2-bromo-7-{2-(4-pyridyl)ethen-1-yl}fluorenone], and the dinuclear complex [{Mo(TpMe,Me)(NO)Cl}2(µ-L3)] 3 [L3 is the bridging ligand 2,7-bis{2-(4-pyridyl)ethen-1-yl}fluorene] which lacks the ligand-centred redox activity. A combination of EPR and UV/VIS/NIR spectroelectrochemical techniques was used and showed how the separate metal-centred and ligand-centred reduction processes lead to quite distinct and characteristic spectroscopic signatures, such that it was possible to assign the sequence of reduction sites as ligand–metal–metal–ligand. The initial reduction of the bridging ligand in 2 results in a much larger separation between the two Mo(0)/Mo(I) couples (240 mV) than occurs in complexes where the bridging ligand is not redox-active.

The STOBBE Condensation with Thienyl Ketones – a synthesis of benzothiophene derivatives

Abstract: The condensation of methyl-2-thienyl-, and phenyl-2-thienyl-ketones with dimethyl succinate in the presence of potassium t-butoxide or sodium hydride gave predominantly the (E)-half-esters11a and 1d, which were cyclised to benzothiophene derivatives 2a and 2e, respectively. Methanolysis of the derived anhydrides 3a and 3 b led to the formation of the half-esters 1c and 1f. The (E)-dibasic acids 1b and 1e were converted by concentrated sulphuric acid to the lactones 4a and 4b. The methoxy-acid 2h gave upon such treatment the fluorenone derivative 5.

Process for making fluorenones

Abstract: A process for the oxidation of a fluorene compound to a corresponding fluorenone compound comprises treating the fluorene compound with an oxidizing gas in the presence of a solid alkali metal or alkaline earth metal oxide or hydroxide or a concentrated aqueous solution thereof in a reaction mixture containing a non-aqueous heterocyclic nitrogenous solvent, wherein the reaction mixture is free of a phase transfer agent, for a time sufficient and at a temperature sufficient to convert the fluorene compound to the fluorenone compound

Green light-emitting region-regular poly(9,9-dihexylfluorene-co-fluorenone) prepared from solvent-free oxidative coupling polymerization

Abstract: Soluble green light-emitting poly(9,9-dihexylfluorene-co-fluorenone) was synthesized by solvent-free oxidative coupling polymerization of 9,9-dihexylfluorene in a facile one-step reaction. The polymers were characterized by FT-IR, 1H NMR, 13C NMR, UV-Vis and fluorescence spectroscopy. The region-regular structure of the polymer linking at 2, 7′-position on the fluorene moieties was obtained. The FT-IR spectra of the polymers showed fluorenone vibration. The fluorescence spectra of the solid thin film of the polymers displayed green light-emitting, which was emitted from fluorenone moieties produced in the polymerization process.