Phenanthrenequinone, reactions

Phenanthrenequinones. Reaction of benzil with C K in THF results in cyclization to phenanthrenequinone (equation I). A similar reaction of p,p -dimethylbenzil gives 3,6-dimethylphenanthrenequinone (72% yield). 

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],... 

The solid state photochemical reaction of indole with 1,4-naphthoquinone yielded 5H-dinaphtho(2,3-a 2, 3 -c)carbazole-6,ll,12,17-tetrone in addition to 2-(3-indolyl)-1,4-naphthoquinone which was also the only product in the solution photoreaction. Solventless thermochemical reactions of indole with phenanthrenequinone in the presence or absence of zinc chloride gave 10-(lH-indol-3-yl)-9-phenanthrenol and 9,10-dihydro-9-(lH-indol-3-yl)-10-(3H-indol-3-ylidene)-9-phenanthrenol or 10,10-di-lH-indol-3-yl-9(10H)-phenanthrenone, respectively. All of these products were only obtained in trace amounts in corresponding solution reactions, and are different from the adduct 10-hydroxy-10-(lH-indol-3-yl)-9(10H)-phenanthrenone obtained in the solution photoreaction (Wang et al., 1998). 

Biphenyldicarboxylicacids.1 Phenanthrenequinone (1) isoxidized by oxygen in the presence of CuCl in pyridine to 2,2 -biphenyldicarboxylic acid (2) in high yield. Under the same conditions the monoimine 3, prepared in situ, is oxidized to 4. Amino and hydroxyl substituents interfere with this reaction, but alkyl, nitro, and halo groups are well-tolerated. 

Peterson reaction, 303, 331, 424 Phase-transfer catalysts, 403-407 Phenanthrenequinone, 140, 141 Phenanthrenes, 307 Phenanthro[l,2,3]thiadiazole, 55 Se-Phenyl benzeneselenosulfonate, 407-408 2-Phenylbenzofurane, 218 Phenylboronic acid, 408-410, 513, 514... 

As an extension of the successful Strecker reaction under high pressure [83], a heterocyclic version of this reaction was investigated by us but met with very limited success. For example, 1 equivalent of 1,2-diacetylbenzene (152) with 1,2-diaminobenzene (153) and TMSCN (2.4 equivalents) afforded 5,6,11,12-tetrahydro-6,11 -dimethyldibenzo[b,f][ 1,4]diazo-cine-6,ll-dicarbonitrile (154), albeit only in 17% yield in one step. A similar reaction of cyclohexane-1,2-dione (155) with 153 produced 1,2,3,4,5,10-hexahydrophenazine-4a,10a-dicarbonitrile (156) in 13% yield along with the aromatized product, 1,2,3,4-tetrahydrophenazine (157) (Scheme 42). However, similar attempts with other diketones, such as 2,5-hexanedione, 2,3-butadiene, and 9,10-phenanthrenequinone, met with failure, either giving a complex mixture of products or well known and commercially available product possessing a pyrazine skeleton [100]. 

Molecular electrostatic potentials have been used to explain the regioselectivity exhibited in the Diels-Alder cycloaddition reactions between 1-trimethylsilyloxy-butadiene and the quinones 5-formyl-8-methyl-1,4-naphthoquinone, 5-methoxy-7-methyl-1,4-phenanthrenequinone, and 5,6,7-trimethyl-1,4-phenanthrenequinone.128 The intramolecular Diels-Alder reaction of masked o-benzoquinones (123) with a variety of dienes provides adducts (124) which rearrange to functionalized ris-decal ins (125) with complete stereocontrol of up to five stereocentres. This methodology ... 

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]. 

Phenanthrenequinone from benzoin. The photocyclization of stilbene to phenanthrene requires a trans to cis isomerization. This step can be circumvented by reaction of benzoin with phenylboric acid to form the 1,3-dioxoborole 2. This adduct can be converted to phenanthrenequinone by photocyclization in the presence of diphenyl diselenide as the oxidant. 

Sitlani A, Long EC, Pyle AM, Barton JK. DNA Photocleavage by phenanthrenequinone diimine complexes of rhodium(III) shape-selective recognition and reaction. / Am Chem Soc 1992 114 2303-12. 

Estimates of the triplet energy level of a molecule may be made by observing whether it can accept or transfer energy to several other molecules. Hammond and co-workers42 have shown that ds-trans interconversions of piperylene, 2-pentene, and 1 2 dichloroethylene may be affected by many photosensitizers. The stationary states of the sensitized ds-trans ratios of piperylene with various donors were found to form a coherent pattern if triplet energy transfer was assumed as the key step in the photochemical reaction. From these results they were able to infer the presence and the energies of the triplet states of acetone, phenanthrenequinone, and fluorenone, for which phosphorescence data are not available. The triplet levels were estimated as >70, 65, and 62 kcal./mole, respectively. 

Transition metal complexes containing catecholate and semiquinone ligands have been reviewed by Pierpont and Buchanan.336 The syntheses of catecholate adducts of platinum group metals by oxidative addition of benzoquinone (BQ) have been reported (reaction 92).337 The coordinated catechol can then be oxidized to the semiquinone with silver ion (reaction 93). In reactions (92) and (93), L M = lr(Cl)(CO)(PPh3)2] and the benzoquinones (BQ) are shown in (146). The oxidative addition of phenanthrenequinone to [Ir(Cl)(CO)(PPh3)2] has also been cited.338... 

Tamarkin, D., Rabinovitz, M. Hyper-acyloin condensation from simple aromatic esters to phenanthrenequinones a new reaction of CsK. J. 

Phenylcyclone. Mol. wt. 382. 43, m.p. 273°, dark green. The reagent is prepared in 90% yield by the condensation of phenanthrenequinone with dibenzyl ketone. Mackenzie found it more reactive than tetraphenylcyclopentadienone in Diels-Alder reactions. 

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. 

Maruyama, K., Otsuki, T., Naruta, Y., Photochemical Reaction of 9,10 Phenanthrenequinone with Hydrogen Donors Behavior of Radicals in Solution as Studied by CIDNP, Bull. Chem. Soc. Jpn. 1976, 49, 791 795. 

Another complicating factor is the role played by oxygen. In some cases oxygen appears to retard reaction and in others to accelerate. In many cases the overall course of reaction is dependent on the presence or absence of oxygen. This is illustrated in Fig. 2 for the reaction of phenanthrenequinone with ethyl acetate. In degassed solution, the spectra determined after various periods of irradiation presented an appearance very similar to Fig. 1 and the quantum yield was unity 132>. When degassing was omitted, results such as illustrated in Fig. 2 were obtained and quantum yields were variable and less than unity. 

Hammond and collaborators as part of their extensive studies on photosensitized reactions. Examples include (a) cis-trans isomerization of olefins sensitized by biacetyl 42,64,65,176 2,3-pentanedione 64>65>, benzil 64,65,89)> a. and /3-naphil 64>, and phenanthrenequinone 30-65> (b) diene and anthracene dimerizations sensitized by biacetyl 9>45>94>, 2,3-pentanedione 4,162)j camphorquinone 04>, benzil 84,162) and / -naphthil 94>, and (c) the quadricyclene-norbomadiene interconversion sensitized 66> by benzil. 

Phosphines undergo cycloaddition with diones in the dark 120>. Recently, a report appeared 77> describing irradiation of phenanthrenequinone in wet benzene containing triphenylphosphine. The product was considered to be a hydrate of a species such as 27 intermediacy of 28 was also considered possible. No reaction was observed in the absence of water. 

Reexamination of these reactions beginning in 1965, mainly using 9,10-phenanthrenequinone (PQ), has shown that 1,4-dioxenes are only one of several possible types of products and jure not obtained at all in certain cases. All of the results reported before 1965 thus serve to delineate the scope of the reaction but do not establish structures of products and certainly provide no mechanistic insights. The more recent results are collected in Table 3. The following scheme serves as a reasonable working hypothesis in the light of these results. The essential features are excitation of the dione (direct excitation of olefin... 

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