Nitro fluorenes

Die Reaktion lauft wahrscheinlich iiber das Oxim so wird z. B. aus Kalium-9-ari-nitro-fluoren in 39%iger Ausbeute Fluorenon-oxim1 erhalten. 

Facial selectivities of spiro[cyclopentane-l,9 -fluorene]-2-ones 30a-30e were studied by Ohwada [96, 97]. The carbonyl tz orbital can interact with the aromatic % orbital of the fluorene in a similar manner to spiro conjugation [98-102]. The ketones 30 were reduced to alcohols by the action of sodium borohydride in methanol at -43 °C. The anti-alcohol, i.e., the syn addition product of the reducing reagent with respect to the substituent, is favored in all cases, irrespective of the substituent at C-2 or C-4 of the fluorene ring (2-nitro 30b syn anti = 68 32), 4-nitro... 

Epoxidation of substituted spiro[cyclopentane-l,9 -fluorene]-2-enes 68 with a peroxidic reagent was studied [98], The spiro olefins react with m-chloroperbenzoic acid (mCPBA) in chloroform at 3 °C to give a mixture of the epoxides. In all cases (2-nitro (68b), 4-nitro (68c), 2-fluoro (68d) and 2-methoxyl (68e) groups), the iyn-epoxides, i.e., the syn addition of the peroxidic reagent with respect to the substituent, is favored. For example, for 6 nsyn anti = 63 31 for 68c syn anti = 65 35. Thus, a similar bias is observed in both the reduction of the carbonyl derivatives of 30 and the epoxidation of the derivatives of 68. 

Charge-transfer adducts are formed with the gold(I) trimers [Au3(MeN=COR)3] (R = Me, Et), which act as electron donors, and organic electron acceptors as nitro-9-fluorenes. The structures of these adducts involve mixed stacks in which the gold trimers and the planar nitro-fluorenes are interleaved.3130 No luminescence has been observed from these solid charge-transfer adducts, which is not surprising since the luminescence of [Au3(MeN=COR)3] is a property that is associated with the supramolecular organization in the solid. 

Nitropolycyclic aromatic hydrocarbons have recently been identified in various foods. In smoked sausages, 1-nitropyrene, 2-nitronaphthalene, and 2-nitro-fluorene have been found in concentrations of about 4.2, 8.4, and 19.6 ng per g, respectively this is comparable with the levels found in roasted coffee beans (2.4, 4.0, and 30.1 ng per g). 

DC056 Tang, X., and R. Edenharder. Inhibitions of mutagenicity of 2-nitro-fluorene, 3-nitrofluaranthene and 1 -nitropyrene by vitamins, porphyrins and related compounds, and vegetable and fruit juices and solvent extract. 

Products (and their mutagenicities) of the gas-phase reactions of these and other 2- to 4-ring PAHs (fluorene, naphthalene, etc.) carried out under simulated atmospheric conditions should be consistent with the nitroarenes and nitro-PACs that have been identified in ambient air. This criterion has been well established over the years in environmental chamber studies conducted in several laboratories (e.g., see reviews by Atkinson and Arey, 1994 and Arey, 1998a articles by Kamens et al., 1994 Fan et al., 1995 Feilberg et al., 1999a and references therein). 

So erhalt man beispielsweise bei der Nitrierung von Fluoren, Fluoranthen, Binaphthyl oder Triphenylen mit Distickstofftetroxid in Dichlormethan in Gegenwart von Methan-sulfonsaure in 0,5 bis 2 h die entsprechenden Nitro-arene in ausgezeichneter Ausbeute3,4 z.B. ... 

Triphenylmethane derivatives, rhodamines, and nitro derivatives of 9-dicyanomethylene fluorene are characterized by -type photoconductivity. 

Thermochemical data are available (Ref 2) on the heats of combustion and formation for all five isomers, on the heats of nitration from various Dinitrotoluenes for the 23,4-, 2,4,5-, and 2,3,6-isomers, and on the heats of crystn for the 2,3,4- and 2,4,5-isomers. Data are also available (Ref 1) on the shock sensitivities of all of the isomers except 2,3,6-, and on the rates of decompn at 140° of the 23,4-, 2,4,5-, and 23,5-isomers. The detonation pressure and the temp coefficient of decompn between 140 and 180° have been measured for the 2,4,5-isomer 2,3,4- and 2,4,5-TNT form addition compds ( 7r-complexes ) at 1 1 molar ratio with several polycyclic aromatic hydrocarbons (naphthalene, acenaphthene, fluorene, phenanthrene and anthracene) (Ref 2). 2,4,5-TNT forms complexes with 4-aminozaobenzene, 4-aminoacetophenone, bis (2 hydroxy ethyl) amine, and tris (2-hydroxy-ethyl) amine (Ref 1). The first two have a 1 1 molar ratio, the third 1 2, and the fourth 2 1. Upon heating, the two 4-amino compds react with replacement of the 5-nitro group, as discussed below... 

Ethyltbio-ethen- -0-ethylester-0-(4-nitro-phe-nylester) XII/1, 567 -fluorid-bydrazid E2, 436 -fluorid-isocyanat E2, 436 Fluoren-9- -0,0-diethylester XII/1, 569 Furan-2- -0,0-diethylester E2, 442 Furan-2- -O.O-dimethylester E2, 442... 

It is the interaction of the above requirements that has made the search for acceptor molecules difficult. To achieve the desired reduction potential, it is necessaiy to attach electron-withdrawing substituents, such as nitro and dicyanomethylene, on a parent aromatic ring system such as fluorene (Kuder et al, 1978). Unfortunately, many of these compounds show severe electron trapping and are highly polar. Also, the introduction of electron-withdrawing substituents frequently reduces the solubility such that amorphous layers with high acceptor concentrations cannot be prepared. 

Fluoren 2,7-Dichlor-9-hydroximino-4-nitro- E14b, 309 (aus Keton)... 

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