4-amino-9-fluorenone

Amino-fluorenon 14, 113, II68. 4-Amino-fluorenon 14, 113, II69. 

The Balz-Schiemann synthesis can be applied not only to substituted anilines but also to aminobiphcnyls1,131 or amino-substituted fused polyaromatic compounds, such as naphthalene,1114,119,129 anthracene,136 phenanthrene,1135 acenaphthene,133 fluorene,1,131,134 benzanthracene,130 136 pyrene,136 chrysene,136 fluoranthene,131 fluorenone,1,131 anthra-quinone,1,137,139,140 benzanthrone,1,117,118 phenanthraquinone,138 or xanthone.132 Fluorinated pyridines,1,141"146 methylpyridincs,126,147 149 pyridinecarboxylic acids,150 quinolines,1,151 isoquinolines,152 quinazolone,1 thiazoles,153,154 isothiazoles,156 benzothiazoles,157 thiadiazoles,155 and thiophenes154 can also be obtained from the corresponding aminated heterocycles. Modified Balz-Schiemann methods are recommended for amino nitrogen-containing heterocycles, the diazonium salts of which are rather water-soluble and unstable (a violent explosion was reported for pyridine-3-diazonium tetrafluoroborate).159 These new techniques have also been specially adapted for pyrazol-, imidazol-, or triazolamines which fail to react under classical conditions.158... 

The quadrupole mass spectrometer which was used for these initial studies could provide only limited insight into the formation or structures of these unusual ions from fluorene and amino PAH. Experiments using substituted fluorenes, such as 1-, 2-, and 9-methylfluorene, 9-phenylfluorene, and carbazole, revealed that the (M + 14) ion did not form if the C-9 position was blocked. Knowing that the (M + 14) ion was formed by a reaction at the C-9 carbon, two possible structures could be drawn for this anion. One possibility would be 9-methylfluorene (structure I), which could arise from the addition of CH2 to fluorene. Similar formation of adducts from methane buffer gas under NICI conditions has been reported (7, 8). Alternatively, fluorene could lose the two hydrogens at the 9-position and add oxygen to form 9-fluorenone (structure II)... 

Hydrazoic acid attacks the carbonyl and carboxy groups of fluorenone-l-carboxylic acid simultaneously giving mainly 4-amino-phenanthridone together with some acidic material, presumably phenanthridone-4-carboxylic acid.89 The latter is best prepared by prior protection of the carboxy group with pyrrolidine.106 112 The increase in strain associated with the conversion of 4,5-dimethyl-fluorenone into 1,10-dimethylphenanthridone is reflected in the relatively low yield (50%) obtained under Schmidt conditions.22... 

Halogenated and amino functional benzophenones Fluorenone derivatives Anthraquinone derivatives... 

A The initial reaction produces the diazonium salt from the amino group of the substituted benzophenone. In the presence of Ciu warming results in the loss of nitrogen and the generation of an aryl radical. Intramolecular attack at the ortfw position of the adjacent phenyl ring yields the tricyclic molecule fluorenone (Scheme 8,21),... 

A halo acid, p-(/S-bromoethyl)-benzoic acid (87%), a hydroxy acid, yS-hydroxyisovaleric acid (9%), and an acetylated amino acid, p-(/3-acetyl-aminoethyl)4>enzoic acid (78%), have been made by this method. Attempts to prepare 3-nitro- and 4-hydroxy-benzoic acids from the corresponding acetophenones have failed. Oxidation of the methylene group of 2-acetylfluorene occurs during the reaction to give fluorenone-2-car-boxylic acid (60%). ... 

On the basis of the above findings, it can be concluded that grafting efficiencies and curing rates for commercial systems may be improved more easily by employing polymers having pendant amino groups rather than fluorenone moieties. 

The 9-phenyl-9-fluorenyl (PhFl, 118, Scheme 56) amino-protecting group has been proposed by Christie and RapoportF as it is significantly more stable to solvolysis in acid conditions than the trityl group because of the antiaromatic character of the fluorenyl cation. In fact, solvolysis of Trt-Cl is 6000 times faster than PhFl-Cl.f The AI -PhFl amino acid derivatives are prepared with PhFl-Br (commercially available or prepared from fluorenone and phen-yUithium and subsequent substitution with HBr) and lead nitrate, which is required to trap the bromide (Scheme 56).F f2i] lead-free alternative using nitromethane as solvent has also been reported. ... 

Analogous ring closure to give fluorenones is also possible 2-amino-4 -methyl-5-nitrobenzophenone gives 6-methyl-2-nitrofluorenone in 75% yield on diazotization and three hours warming at 50°.798 804... 

A novel procedure for the preparation of acids which ultimately contain a free amino group consists in the reduction of a nitrile with diisosbutvlalane followed by the sequential addition of the hydrogenphosphonate, and hydrolysis Normally the imines have been derived from aliphatic aldehydesor ketones ", simple benzenoid aldehy-desi3i,i33,142,146,156,16, 277-287 j g Q es including fluorenone or aldehydes based on... 

Quinine, as a jS-amino-alcohol, cannot be satisfactorily oxidized under standard Oppenauer conditions however, it can be oxidized completely at room temperature to quinidinone in dry, deoxygenated DMF, by fluorenone and sodium hydride.It is of interest that little fluorenol is obtained as a result of the hydride transfer, and virtually none (only 1%) is obtained if the oxidation is conducted at -50 C instead the major reduction product is the pinacol derived from fluorenone. This presumably arises by condensation of the carbanion, derived from fluorenol in the presence of strong base, with unchanged fluorenone. 

Ci jOaN 9-Keto-l-fluorenecarboxanude KOBr l-Amino-9-fluorenone ... 

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