Polycyclic fluorenone

Keumi et al. (1989) describe hydro-de-diazoniations of arenediazonium tetrafluo-roborates using chlorotrimethylsilane, (CH3)3SiCl), in tetrahydrofuran or tetra-hydrofuran/A A-dimethylformamide mixtures. Excellent yields were obtained with polycyclic arene derivatives such as 2-fluorene-, 2-fluorenone-, and 1-pyrenediazo-nium tetrafluoroborate and other similar diazonium salts. In a modification of this method 2-halogenofluorenones can be synthesized (see Sec. 10.6). 

Polynitro derivatives of monocychc aromatic systems (trinitrobenzene, trinitrotoluene, tetranitro-iV-methylaniline, trinitrophenol, etc.) have long been used as explosives [1]. It has been found that a series of polynitroderivatives of biphenyl, diphenylmethane and 1,2-diphenylethylene (stilbene) are explosives liable to detonate on grinding or impact [2]. The same may be true of other polynitro derivatives of polycyclic systems not normally used as explosives (e.g. polynitro-fluorenones, -carbazoles, etc. Penta- and hexa-nitrobenzophenones are also high-energy explosives [3]. The thermal stability of 33 polynitroaromatics was studied by DTA [4]. Two empirical equations relating the heat of decomposition to the heat of detonation have been developed and used to calculate the heats of detonation for 47 polynitroaryl compoimds [5]. 

In detail, several alkylated and nonalkylated polycyclic aromatic compounds (PAHs) were detected and dominated by acenaphthene with a maximum concentration of 24 pg/L in sample B. Total concentrations of methyl- and dimethylnaphthalenes reached 5.1 pg/L and 24 pg/L, respectively. Tricyclic aromatic compounds and oxygenated PAH species were detected comprising e.g. phenanthrene, 9H-fluorenone and acenaphthenone. Methylated and dimethylated benzo(b)thiophenes as well as dibenzothiophene were also present. 

Polycyclic aromatic compounds Dibenzofurane 1,-1 Dibenzophenone 1,-1 Fluorenone b)... 

Alben (1980) chlorinated a coal-tar leachate that contained many polycyclic aromatic hydrocarbons and demonstrated that many hydrocarbons were significantly reduced in concentration. Oxygenated compounds, such as dibenzofuran (17), were formed, together with low concentrations of chlorinated and brominated derivatives of naphthalene and fluorene. Chlorinated polycyclic compounds have been demonstrated to occur in drinking water samples (Shiriashi et al., 1985), including mono-and dichloro derivatives of naphthalene, fluorene, dibenzofuran, phenanthrene, fluoranthene, and fluorenone (Figure 5.3). 

Intramolecular or partially intramolecular cycloaddition reactions are extremely useful tools in the synthesis of polycyclic molecules, since they can allow the construction of several rings in a single step. Preliminary studies indicate that this general principle also holds for partially intramolecular versions of the palladium-catalyzed cocycloaddition of arynes and alkynes. For example, benzo[fc]fluorenones 144a-d, which constitute the polycyclic skeleton of the kinamycin family of antitumour antibiotics, can be obtained by [2+2+2] cy-... 

The first account of the indeno[2,l-a]fluorene core in the literature dates to 1939 when Weizmann investigated polycyclic structures and their potential carcinogenic properties [23]. Intramolecular Friedel-Crafts acylation of 3,6-diphenylphthalic anhydride (113) in refluxing CS2 afforded fluorenone carboxylic acid 114 (Scheme 33). Acid chloride formation and subsequent cyclization in concentrated sulfuric acid generated the parent indeno[2,l-a]fluorene dione 115 in 5% yield with respect to 113. This was reaffirmed by Deuschel in 1951 where 115 is obtained in 72% under the same conditions [26]. 

On the other hand, a variety of aromatic ketones have proved to be reactive. Polycyclic aromatic ketones such as anthrone, fluorenone, and xanthone all undergo successful Ru catalyzed copolymerization with 1,3-divinyltetramethyl-disiloxane [12], see Figure 8. It has also been possible to incorporate phenanthrene units, which strongly absorb in ultraviolet and fluoresce, into an fl/l(carbosilane/siloxane) by copolymerization of 2-acetylphenanthrene and 1,3-divinyltetramethyldisiloxane [13]. Initially, the molecular weight of these materials was quite low [12]. 

Larocket fl/. in 2000 developed the fluoren-9-one synthesis by the cyclocarbonyla-tion of ort/zo-halobiarys with a commercially available Pd(PCy3)2 catalyst [17] This procedure was initiated by the palladium(0) and could be utilized to the synthesis of polycyclic and heterocyclic fluorenones containing the fused isoquinoline, indole, pyrrole, thiophene, benzothiophene, and benzofuran rings (Table 15.12). 

---