2.5- Dinitro-9-fluorenone

Another interesting characteristic of the trinuclear [Au3(CH3N = COR)3] (R = Me, Et) complexes is that they can act as electron donors with organic acceptor molecules such as nitro-9-fluorenones [46]. Thus, they form adducts with 2,4,7-trinitro-9-fluorenone (deep yellow and red R=Me, Et, respectively), 2,4,5,7-tetranitro-9-fluorenone (red R = Me), 2,7-dinitro-9-fluorenone (red R = Et). The solid state structures of the complexes formed with [Au3(CH3N = COMe)3] and 2,4,7-trinitro-9-fluorenone or 2,4,5,7-tetranitro-9-fluorenone consist of planar gold(I) trimers interleaved with the nitro-9-fluorenones to form columns in the crystal. The distances between the faces of both portions indicate that interactions occur between the gold atoms, rich in electronic density, and the nitroaromatic portion of the electron acceptor. The difference between them stems from the greater complexity of the... 

Similarly, chemical modification of Au MeN = COMe)3 also destroys its luminescent behavior. For example none of the oxidation products, Au3Xn(MeN = COMe)3 (n = 2, 4, or 6), shown in Scheme 3 are luminescent [45]. AuT3(MeN = COMe)3 and Au MeN = COMe)3 form several crystalline charge transfer complexes deep yellow Au MeN = COMe 2,4,7-trinitro-9-fluorenone, red AuI3(MeN = COMe)3 - 2,4,5,7-tetra-nitro-9-fluorenone, red Au MeN = COEt)3 2- 2,7-dinitro-9-fluorenone and red Au MeN = COEt)3 2- 2,4,7-trinitro-9-fluorenone [46]. The... 

Standard solutions w-dinitrobenzene, fluorenone, acetone-2,4-dinitro-phenyl-hydrazine, benzylidene acetone and azobenzene (all 1% (w/v) in toluene). 

The synthesis of 2-monosubstituted or 2,2 -disubstituted precursor compounds can be achieved by two different routes direct electrophilic aromatic substitution or the use of substituted derivatives of 9-fluorenone. hi many cases, the first route is complicated due to the fact that the two fluorene moieties in spirobifluorene react chemically independently of each other. The formation of products monosubstituted in the 2-position is therefore often accompanied by the formation of byproducts (Fig. 6). A good example is the nitration of spirobifluorene, which was investigated by Weisburger and coworkers [23]. They discovered that a careful control of reaction times and conditions allowed for the formation of 2-nitro-9,9 -spirobifluorene or 2,2 -dinitro-9,9 -spirobifluorene as the main product. Especially in the case of 2-nitro-9,9 -spirobifluorene, however, the conversions are low because the reaction must be quenched before a suitable amoimt of the dinitro compound is formed. 

The nitration of fluorene with HNO3 in glacial AcOH at 55-85 °C gives 2-nitrofluorene in excellent yield. Excess of HNO3 leads mainly to the 2,7-dinitro-compound, with smaller amounts of the 2,5-isomer. Conventional nitration of fluorenone shows poor selectivity, but nitration with Cu(N03)2 ACOH-AC2O for 90 minutes at 40 °C gives only 2-nitrofluorenone, in good yields. ... 

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