Oxidation of phenanthrene

Diphenic acid. Phenanthrene upon oxidation in acetic acid solution at 85° with 30 per cent, hydrogen peroxide gives diphenic acid (diphenyl-2 2 -di-carboxyHc acid) no phenanthraquinone is formed under these experimental conditions. The reaction is essentially an oxidation of phenanthrene with peracetic acid. (For another method of preparation, see Section I V,74.)... 

Barbas JT, ME Sigman, R Dabestani (1996) Photochemical oxidation of phenanthrene sorbed on silica gel. Environ Sci Technol 30 1776-1780. 

Region Arene Oxides of Phenanthrene. Comparative Solvolytic Rate Constants of K-Re-gion and Non-K-Region Arene Oxides , J. Am. Chem. Soc. 1976, 98, 2965 - 2973. 

Of the various routes to diphenic acid, the present method and the peracetic acid oxidation of phenanthrene 7 seem to be the simplest. The yields are equally good. 

Ghosh, D. K. Mishra, A. K. (1983). Oxidation of phenanthrene by a strain of Micrococcus Evidence of protocatechuate pathway. Current Microbiology, 9, 219-24. 

Rusyanova [25] describe the oxidation of phenanthrene to various products (using the V2Os catalyst above) by power rate equations according to a parallel reaction scheme... 

Phenanthrene is oxidized more easily than benzene or naphthalene. Chromic acid oxidation of phenanthrene forms a substance known as phenanthraquinone. Which structure, A, B, or C, would you expect to be formed most readily by oxidation of phenanthrene Expiain. 

Diphenic acid has been prepared by the reduction of diazotized anthranilic acid with cuprous ion,6 Ullman coupling of potassium o-bromobenzoate,6 and oxidation of phenanthrene or phen-anthrenequinone with various oxidizing agents.7 The latter methods have been reviewed recently.7 The ozonolysis method has also been carried out in solvents 8 that do not react with the zwitterion intermediate. ... 

Naphthalene 1,2-oxide (136), a non-K-region epoxide, shows low thermal stability. Anthracene 1,2-oxide, on the other hand, is stable at ambient temperatures for several weeks. Preparation of (+ )-(lR,2S)-anthracene 1,2-oxide (137), using the above method, constitutes the first example of preparation of an optically pure arene oxide. However, the non-K-region oxides of phenanthrene, namely, its 1,2- and 3,4-oxides (47 and 48), obtained from chiral precursors, racemize fast.66 Perturbational molecular orbital calculations indicate that epoxide-oxepin valence tautomerism is possible. However, the oxepin could not be detected by NMR. 

Diphenic acid (Expt 6.151) is obtained when phenanthrene is oxidised with 30 per cent hydrogen peroxide in glacial acetic acid solution at 85 °C. No phenanthraquinone is formed under these conditions (compare the oxidation of phenanthrene with acid dichromate, Expt 6.128) the reaction is essentially an oxidation by peracetic acid of the reactive 9,10-positions in phenanthrene. 

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]. 

Several approaches to dibenzo[b,c/]pyranones have been reported. The simplest, with a 45% yield, is the TiCVphotocatalysed oxidation of phenanthrene <06CC2804>. 

Arene oxides. The acetone-oxone system (11, 442) converts several polycyelic aromatic hydrocarbons into the K-region oxide, often in synthetically useful yield. Thus the 9,10-oxide of phenanthrene is formed with this system in 60% yield. 

Diphenic acid itself can be prepared without isolation of phenanthrenequinone by direct oxidation of phenanthrene with hydrogen peroxide in refluxing acetic acid. ... 

Preparation. By oxidation of phenanthrene with CrOs in acetic acid or with KrCrOjindil. H3SO4. -"... 

Olefins, see also Catalytic method (p. 989). Djerassi and Engle report one experiment on the oxidation of phenanthrene with ruthenium tetroxide in carbon tetrachloride the reaction mixture contained considerable starting material and a small amount of phenanthrenequinone. Berkowitz and Rylander oxidized cyclohexene in the same way and obtained adipaldehyde in low yield as the only isolated product they regard the method as unsatisfactory for the production of aldehydes and acids because these substances are strongly adsorbed on the ruthenium dioxide formed. 

S Bohmer, K Messner, E Srebotnik. Oxidation of phenanthrene by a fungal laccase in the presence of 1-hydroxybenzotriazole and unsaturated lipids. Biochem. Biophys. Res. Commun. 244(1 ) 233-238, 1998. 

The oxidation of the unsaturated compound II gives, in addition to the acid HI already mentioned, a small amount of a monobasic acid, C17H14O7 (m.p. 304° methyl ester, m.p. 252°), which is regarded as 2,3,8-trimethoxy-xanthone-5-carboxylic acid (VI). Its formation was considered to be analogous to the formation of fluorenone in the oxidation of phenanthrene... 

Figure 4.12. Proposed mechanism of wet air oxidation of phenanthrene. Compounds in brackets are postulated intermediates. Reprinted with permission from Water Research, Vol. 22, Larson et al. Some intermediates in the wet air oxidation of phenanthrene adsorbed on powdered activated carbon. Copyright 1988 Pergamon Press PLC.

Many studies of wet air oxidation have claimed highly efficient conversion of DOC to low molecular weight polar species such as short-chain organic acids and diacids. Not much is known about the mechanisms of the reactions taking place in wet oxidation. Hydroxyl radicals have been suggested as intermediates, but very little information of a mechanistic nature is available to prove or disprove this hypothesis. In a study of wet air oxidation of phenanthrene (Larson et al., 1988), the structures of the partial oxidation products identified suggested a radical mechanism that could have been initiated by -OH (Figure 4.12). 

The epoxides of several polycyclic aromatic hydrocarbons have been prepared by the use of a large excess of oxidant in a bipha-sic Oxone-ketone system under neutral conditions, as shown for the oxidation of phenanthrene (eq 11). However, the use of isolated dioxirane solutions is more efficient for the synthesis of reactive epoxides, since hydrolysis of the product is avoided. A number of unstable epoxides of various types have been produced in a similar manner, as discussed for Dimethyldioxirane and Methyl(trifluoromethyl)dioxirane. 

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