Phenanthrene-9,10-quinone, reaction

Weak to moderate chemiluminescence has been reported from a large number of other Hquid-phase oxidation reactions (1,128,136). The Hst includes reactions of carbenes with oxygen (137), phenanthrene quinone with oxygen in alkaline ethanol (138), coumarin derivatives with hydrogen peroxide in acetic acid (139), nitriles with alkaline hydrogen peroxide (140), and reactions that produce electron-accepting radicals such as HO in the presence of carbonate ions (141). In the latter, exemplified by the reaction of h on(II) with H2O2 and KHCO, the carbonate radical anion is probably a key intermediate and may account for many observations of weak chemiluminescence in oxidation reactions. 

The chemical sensitization effect was 0.006 (calculated from the quantum yield of the photochemical transformation of 130 to 131, the yield of 131 obtained with the oxalate/hydrogen peroxide reaction, and the moles of oxalate employed). Higher chemical sensitization efficiencies (about 0.04) were observed when the oxalate/hydrogen-peroxide system was used in the addition of ethyl vinyl ether onto phenanthrene quinone... 

Further evaporation of the reduction mixture precipitates a second fraction whose properties are not very characteristic. This fraction is not a single compound. It gives no characteristic reaction with ferric chloride, showing the absence of a phenolic hydroxyl group, and it must be, therefore, a naphthylaminesulfonic acid or some other amino compound which gives no condensation product with phenanthrene-quinone. 

A different mode of the reaction of dimethylzinc and diethylzinc was observed in reactions with various o-quinones and benzils 122). The treatment of phenanthrene quinone with dimethylzinc gives (XLV), while diethylzinc affords (XLVI). 1,2-Naphthoquinone derivatives also give carbinol ketones with dimethylzinc, while they afford monoethyl... 

Reactions of another type involve cleavage of a carbon-carbon bond. Phenanthrene-quinone is oxidized smoothly to diphenic acid by hydrogen peroxide in warm acetic acid. Use of the reaction in structure elucidation is illustrated as follows. One of five disulfonic acids formed on sulfonation of phenanthrene was converted into the dimethoxyphenanthrene, which on oxidation afforded a dimethoxy-9,10-phenan-threnequinone. Oxidation of this quinone with HjOa-AcOH gave an acidic product... 

By using 10mol% of benzoylquinidine (BQD, la), a variety of acid chlorides reacted efficiently with o-chloranil at — 78 °C in the presence of nonnucleophilic Hiinig base (iPr2EtN, DIPEA) (Scheme 10.2). The desired lactones 2 were produced in up to 91% yield with excellent enantiopurity. On the other hand, o-bromanil and 9,10-phenanthrene quinone were also successfully applied in this cycloaddition reaction. 

The synthetic procedure described is based on that reported earlier for the synthesis on a smaller scale of anthracene, benz[a]anthracene, chrysene, dibenz[a,c]anthracene, and phenanthrene in excellent yields from the corresponding quinones. Although reduction of quinones with HI and phosphorus was described in the older literature, relatively drastic conditions were employed and mixtures of polyhydrogenated derivatives were the principal products. The relatively milder experimental procedure employed herein appears generally applicable to the reduction of both ortho- and para-quinones directly to the fully aromatic polycyclic arenes. The method is apparently inapplicable to quinones having an olefinic bond, such as o-naphthoquinone, since an analogous reaction of the latter provides a product of undetermined structure (unpublished result). As shown previously, phenols and hydro-quinones, implicated as intermediates in the reduction of quinones by HI, can also be smoothly deoxygenated to fully aromatic polycyclic arenes under conditions similar to those described herein. 

Djerassi and Engle showed that stoich. RuOyCCl oxidised phenanthrene to 9,10-phenanthrenequinone (Table 3.5) [239], The first catalytic reaction involving RuO was that of pyrene with RuO /aq. Na(IO )/acetone, giving a mixture of pyrene-4,5-quinone, pyrene-1,6-quinone, the lactol of 4-form-ylphenanthrene-5-carboxylic acid (OsOyH O /acetone was more specific, giving pyrene-4,5-quinone) [240],... 

Only a few qui nones react with sulfur tetrafluoride in the normal way by replacing each carbonyl group by two fluorine atoms. The examples are 9,10-anthraquinone (l),41 phenanthrene-9,10-quinone (2),100 and acenaphthoquinone and its substituted derivatives 3.101102 The reactions proceed at 150-300 C, preferably in the presence of anhydrous hydrogen fluoride. 

Nitration of arenes. Reaction of 1-naphthol with CAN in acetic acid results in 2,4- and 4,6-dinitro derivatives. The reaction with CAN absorbed on silica gel results in 2-nitro- and 4-nitro-l-naphthol in 42 and 38% yield, respectively. Polynuclear arenes are not oxidized to quinones by CAN supported on silica but are converted mainly into mononitro derivatives. Thus phenanthrene is converted into 2-nitrophenanthrene (45% yield) and 3-nitrophenanthrene (28% yield).1... 

With K-region oxides, sodium salts of phenol or cresols also produce addition products. Thus heating a mixture of 1 and sodium phenoxide in dimethylformamide at 100°C under a nitrogen atmosphere produced 9,10-dihydro-frans-9-hydroxy-10-phenoxyphenanthrene (248, 19%), 9-phenoxy-phenanthrene (249, 68%), and traces of 9-phenanthrol and phenanthrene-9,10-quinone. When the reaction was carried in the presence of air, a significant amount of 9-hydroxy-10-phenoxyphenanthrene (250) was formed instead of 248 and 249.150... 

The direct oxidation of arenes to quinones is a reaction with a limited scope [41], Only substrates that form stable quinones give good yields. For example, oxidation of anthracene to stable 9,10-anthraquinone with chromic acid is practiced on industrial scale. Such oxidations are believed to proceed through a series of one-electron oxidation/solvolysis steps. Yields and selectivity may be improved by using a strong one-electron oxidant such as cerium ammonium nitrate (CAN), as in the oxidation of phenanthrene to phenanthrenequinones (Eq. 9) [42]. 

Anthracene and phenanthrene are even less resistant toward oxidation or reduction than naphthalene. Both hydrocarbons are oxidized to the 9,10-quinones and reduced to the 9,10-dihydro compounds. Both the orientation of these reactions and the comparative ease with which they take place are understandable on the basis of the structures involved. Attack at the 9- and 10-positions leaves two... 

Therefore, the method described allows a novel economic as well as ecologically sound synthesis of quinone derivatives. Higher condensed arenes, e.g., anthracene, are converted to the quinones or cleaved to dicarboxylic acids, as in the case of phenanthrene (yield ca. 50 %). Besides MTO, in principle all alkyl- and to some extent also aryl-substituted trioxorhenium compounds, e.g., cyclopropylrhenium trioxide or cyclopentadienylrhenium trioxide, can be used as active catalysts. However, until now MTO apparently constitutes the most active and easy-to-handle catalyst (see Figure 1, p. 439). The solvent of choice for the reaction and the workup procedure, is concentrated acetic acid, also used to dilute the H2O2 (85 wt.%), yielding a water-poor reaction medium which is advantageous for the catalyst lifetime. 

Anthracene was oxidized to anthraquinone by warming a mixture of 90 g. of finely powdered hydrocarbon, 0.5 g. of vanadium pentoxide, 76 g. of sodium chlorate, 1 1. of acetic acid, and 200 ml. of 2% sulfuric acid under reflux until a vigorous reaction set in. After eventual brief refluxing, anthraquinone was obtained in 88-91% yield. The method is not suitable for the oxidation of hydrocarbons of the naphthalene or phenanthrene series to the quinones or for oxidation of acenaphthene or fluorene. 

Heterocyclic Synthesis. - The reactions of phosphorus ylides with phenan-threne-9,10-quinone (113) have been used to prepare phenanthrene [9,10-x]-fused compounds with four, five, and six membered heterocyclic rings. (E)-4-carbethoxymethylene-l,2,3,4-tetrahydro-2-quinolones 114 have been obtained from the stereoselective reaction of 3-hydroxy-1,2,3,4-tetrahydroquinoline-2,4-diones and ethyl(triphenylphosphoranylidene)acetate. A -trifluoroacetylanilines 115 react with Ph3P=C02Et producing enamine derivatives 116 as a mixture of (E)- and (Z)-isomers. Enamines 116 are useful precursors for the synthesis of indoles and quinolones. 

Rat liver microsomes also catalyzed benzo[a]pyrene metabolism in cumene hydroperoxide (CHP)-dependent reactions which ultimately produced 3-hydroxybenzo[a]pyrene and benzo[a]pyrene-quinones (Cavalieri et al. 1987). At low CHP concentrations, 3-hydroxybenzo[a]pyrene was the major metabolite. As CHP concentrations increased, levels of quinones increased and levels of 3- hydroxybenzo[a]pyrene decreased. This effect of varying CHP levels was reversed by preincubating with pyrene. Pyrene inhibited quinone production and increased 3-hydroxybenzo[a]pyrene production. Pretreatment with other PAHs like naphthalene, phenanthrene, and benz[a]anthracene nonspecifically inhibited the overall metabolism. The binding of benzo[a]pyrene to microsomal proteins correlated with quinone formation. This suggested that a reactive intermediate was a common precursor. The effects of pyrene on benzo[a]pyrene metabolism indicated that two distinct microsomal binding sites were responsible for the formation of 3-hydroxybenzo[a]pyrene and benzo[a]pyrene-quinone (Cavalieri et al. 1987). 

Except for biacetyl, hexafluorobiacetyl, and benzil, photoreactions of o-quinones and a-diketones have been investigated in solution. Some of these reactions are elegantly clean and quantitative as illustrated in Fig. 1 for the irradiation (4358 A) of a degassed solution of phenanthren-equinone in dioxane where four isosbestic points are observed (a fifth isosbestic point appears at 316 nm). 

In this original and imaginitive approach, a rapid assembly of the phenanthrene core of morphine, containing a novel non-aromatic A ring, was achieved in an intermolecular Diels-Alder reaction between quinone 173 (prepared from 3-methoxy-2-hydroxy benzaldehyde in 7 steps and an overall yield of 35%) and diene 174 (from 1,4-cyclohexanedione monoethylene ketal in 2 steps with an overall yield of 30%), Scheme 20. In one of several unsuccesful attempts to aromatize ring A, an unexpected tandem... 

It should be noted that NBS can cause nuclear bromination when that reaction occurs readily. In the absence of a catalyst it can brominate the nucleus of condensed aromatic compounds such as naphthalene, anthracene, and phenanthrene,399 veratrole, the dimethyl ethers of resorcinol and hydro-quinone,389 and pyrogallol trimethyl ether.390 Pyrocatechol and 2 moles of NBS afford 4,5-dibromopyrocatechol resorcinol and 3 moles of NBS afford 2,4,6-tribromoresorcinol 391,392 and anthranilic or o- or/ -hydroxybenzoic acid with 2 moles of NBS afford the 4,5- or 3,5-dibromo derivatives.391-393 However, nuclear bromination of benzene and toluene is effected by NBS only if equimolar amounts of A1C13, ZnCl2, FeCl3, or H2S04 are added. 

Some aromatic compounds can also react with ozone, although most simple aromatic rings such as benzene derivatives and naphthalene do not. Anthracene reacts with ozone to give anthraquinone in 73% yield after an oxidative workup. Indeed, quinone formation is a more typical example of the reaction of ozone with aromatic compounds (for other oxidative cleavage reactions see sec. 3.8 and for oxidation to phenols and quinones see sec. 3.3). Only a reactive n bond, such as the 9,10 bond of phenanthrene, will oxidatively cleave, and phenanthrene (361) was oxidized to dialdehyde 362 upon treatment with ozone in methanol followed by a workup with potassium iodide in acetic acid. ... 

Certain polycyclic aromatic hydrocarbons can be converted to their epoxides, as typified by the reaction of phenanthrene with DDO (eq 9). Aromatic heterocycles like furans and benzofurans also give epoxides, although these products are quite susceptible to rearrangement, even at subambient temperatures (eq 10). The oxidation of heavily substituted phenols by DDO leads to quinones, as shown in eq 11, which illustrates the formation of an orthoquinone. 7 The corresponding hydroquinones are intermediates in these reactions, but undergo ready oxidation to the quinones. 

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