1530-12-7Relevant articles and documents
Stabilization of Carbanions by Polarization of Alkyl Groups on Nonadjacent Atoms
Bordwell, Frederick G.,Drucker, George E.,McCollum, Gregory J.
, p. 2504 - 2510 (1982)
Equilibrium acidities in dimethyl sulfoxide solution have been found to increase along the series Me, Et, i-Pr, t-Bu for 9-substituted fluorenes when the alkyl group, R, is separated from the fluorene ring by a CH2, S, or SO2 moiety.This is a reversal of
A Kinetic Study on Reduction of 9,9'-Bifluorenylidene by Sodium Isopropoxide
Kajigaeshi, Shoji,Fujisaki, Shizuo,Nakashige, Yasuhiko,Murakami, Sadaaki
, p. 833 - 837 (1982)
The kinetics and mechanism of reduction of 9,9'-bifluorenylidene (1) by sodium isopropoxide (2) in isopropyl alcohol to yield 9,9'-bifluorenyl (3) were investigated spectrophotometrically.The kinetic data suggest that the reduction proceeds autocatalytically, the reduction product 3 acting as the catalyst.It was found that (1) (2) Reactions 1 and 2 are of the first order with respect to 1, but that the former is of the third order with respect to 2, whereas the latter is of the first.The fourth- and third-order rate constants, k1 and k2 for Reactions 1 and 2 were determined to be 3.0 * 10-5 dm9 mol-3 s-1 and 1.1 * 103 dm6 mol-2 s-1, respectively, at 130 deg C.Probable mechanisms for Reactions 1 and 2 have been offered on the basis of the reaction order for each molecular species involved.
PHOTOCHEMICAL GENERATION OF RADICAL ANIONS. AN ACCESS TO NOVEL STRUCTURES
Huber, W.
, p. 181 - 184 (1985)
The preparation of the radical anions of tetrabenzocyclooctatetraene (TBCOT) and fluorene (FLH) by photochemical methods leads to the observation of novel structures.
Fluorenylidene: Kinetics and Mechanism
Griller, D.,Hadel, L.,Nazran, A. S.,Platz, M. S.,Wong, P. C.,et al.
, p. 2227 - 2235 (1984)
Laser irradiation of 9-diazafluorene in solution leads to the formation of a transient species with λmax=470 nm that has been characterized as the triplet carbene and is believed to be in thermal equilibrium with the singlet state, which lies within a few kcal/mol.The singlet carbene is frequently more reactive and tends to dominate the chemistry.For example, in hydrogen donors, the triplet state abstracts hydrogen leading to the 9-fluorenyl radical, which is the only species detected in the flash experiments.However, product studies demonstrate that the predominant reaction path is the insertion of the singlet into C-H bonds (e.g., in cyclohexane), a process that is transparent to the technique of nanosecond laser photolysis.Irradiation of 9-diazofluorene in nitrile solvents results in carbene addition to the nitrile function, leading to nitrile ylides that react rapidly with electron-deficient olefins and present a characteristic absorption band at ca. 400 nm.The singlet carbene has a lifetime of =5 ns and obeys the Skell-Woodworth rules.
Catalytic reductive homocoupling of 9-bromofluorene
Sridevi, Venugopal Shanmugham,Leong, Weng Kee
, p. 6669 - 6670 (2007)
A number of organometallic compounds and inorganic salts, including the group 8 metal carbonyls M3(CO)12 and salts MCl3 (M = Fe, Ru, Os), were tested for their catalytic activity in the reductive coupling of 9-bromofluorene. Among them, FeCl3 was found to show excellent activity (TOF = 1960). The reaction is believed to proceed via a radical mechanism.
Ion Pair Acidities of 9,9'-Bifluorenyl in THF: pK2 Is Lower than pK1
Stratakis, Manolis,Streitwieser, Andrew
, p. 1989 - 1990 (1993)
The second pK's in THF for lithium and cesium salts of 9,9'-bifluorenyl are 0.4 and 2.0 pK units, respectively, lower than the first pK's.
A facile synthesis of dithieno[3,2-b:6,7-b]fluorenes via a tandem annulation-reduction
Xiong, Xiaoli,Liu, Qiancai,Zhang, Jun,Zhu, Min,Wang, Yanmei,Deng, Shiming
, p. 17707 - 17711 (2013)
A concise and facile synthesis of 2,8-disubstituted dithieno[3,2-b:6,7-b] fluorenes starting from 2,7-dihydroxyfluorenone is reported. The key step involved is the tandem annulation-reduction of a 3,6-dichloro-2,7-di(alkynyl) fluorenone using Na2S·9H2O as a sulfur surrogate and reductant. The final dithiophene-fused fluorenes are obtained in reasonable yields (23-43%). The Royal Society of Chemistry.
Preparation of bifluorenes via the synthesis and thermal decomposition of fluorenyltitanium(IV) trichlorides. Molecular and crystal structure of 9,9'-bis(trimethylsilyl)-bi-9,9'-fluorene
Knjazhanski, Sergei Ya,Moreno, Guillermo,Cadenas, Gregorio,Belsky, Vitalii K.,Bulychev, Boris M.
, p. 1639 - 1646 (1999)
The reaction of 9-substituted trimethyltinfluorenes with TiCl4 in hexanes at -40°C leads to unstable fluorenyltitanium(IV) trichlorides which thermal radical decomposition gives quantitatively TiCl3 and corresponding bifluorenes: (C13H9)2 (3a), (9-EtC13H8)2 (3b) and (9- SiMe3C13H8)2 (3c). Crystals of 3c are monoclinic (space group P 21/n), a = 15.059 A, b = 10.254 A, c = 18.172 A, β = 109.20 deg. IIIc dissociates at 100°C to give two radicals which initiate effectively radical polymerizations of methyl methacrylate and styrene.
CHEMICAL AND ELECTROCHEMICAL REDUCTION OF DISELENIDE DICATION SALT, 1,5-DISELENONIABICYCLOOCTANE BIS(HEXAFLUOROPHOSPHATE)
Fujihara, Hisashi,Akaishi, Ryouichi,Nakamura, Akiko,Furukawa, Naomichi
, p. 6375 - 6378 (1990)
The reaction of the diselenide dication salt, 1,5-diselenoniabicyclooctane bis(hexafluorophosphate) (1) with 1,5-diselenacyclooctane (2) gave the corresponding cation radical by single-electron transfer.The dication salt 1 was reduced upon treatment with fluorenyl-lithium, Na2S, NaBH4; it did not deprotonate.The cyclic voltammetry of 1 shows the reversible reduction peak at remarkably low reduction potential.
4a-Methyl-4aH-fluorenes
Neuhaus, David,Rees, Charles W.
, p. 318 - 320 (1983)
The monobenzo derivative (1) of 3a-methyl-3aH-indene and its methyl derivative (3) have been synthesised; although isolable they are reactive, undergoing autoxidation, dimerisation, and other cycloadditions, thermal and acid catalysed aromatisation to fluorenes, and photochemical rearrangement to naphthalenes.
