Phenanthrene reactions

Formylation.2 Dimethylformamide and trifluoromethanesulfonic anhydride form an iminium salt (1) that is more reactive than that formed from dimethylformamide and POCl3, which is generally used for formylation (Vilsmeier reagent). Although the Vilsmeier reagent does not react with naphthalene or phenanthrene, reactions with 1 results in 1-naphthalenacarbaldehyde in 50% yield and in 3-phenanthrenecarbaldehyde in 25% yield. 

In a reaction analogous to that of stilbene, protonated azobenzene iso-merizes at room temperature under irradiation with ( )e, z = 0.27 and = 0.25. Subsequently, the dehydro-photocyclization starts from the photo-stationary E/Z mixture to give protonated benzo[c]cinnoline with a yield of (j) = 0.02. This is parallel to the stilbene-to-phenanthrene reaction, and it proceeds not in concentrated sulfuric acid where the thermal Z -> E reisomerization is fast, but best in ca. 66% acid. Protonated benzo[c]cinnoline and hydrazobenzene are formed, and the latter undergoes the benzidine rearrangement. The complexation with metal ions in azobenzene crown ethers under participation of the n-electrons of the azo group leads to an increase of the E Z quantum yield from 0.25 of the metal free compound to 0.4 to 0.6 in the Ba and Ca "" complexes. The Z E yield decreases from 0.18 to 0.13 and 0.05. If the crown is larger, the values increase to 0.35 and (pz-iE = 0.45. " ... 

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.)... 

Chapter IV. a-Chloromethylnaphthalene (IV,23) benzylamine (Gabriel synthesis) (IV,39) i r.N -dialkylanilines (from amines and trialkyl orthophosphates) (IV,42) a-naphthaldehyde (Sommelet reaction) (IV,120) a-phenyl-cinnamic acid (Perkin reaction using triethylamine) (IV,124) p-nitrostyrene (IV,129) p-bromonaphthalene and p naphthoic acid (from 2 naphthylamine-1 -sulphonic acid) (IV,62 and IV,164) diphenic acid (from phenanthrene) (IV,165). 

A further consequence of association of acylating agents with basic compounds is an increase in the bulk of the reagent, and greater resistance to attack at the more stericaHy hindered positions of aromatic compounds. Thus acylation of chrysene and phenanthrene in nitrobenzene or in carbon disulfide occurs to a considerable extent in an outer ring, whereas acylation of naphthalene leads to extensive reaction at the less reactive but stericaky less hindered 2-position. 

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 addition product, C QHgNa, called naphthalenesodium or sodium naphthalene complex, may be regarded as a resonance hybrid. The ether is more than just a solvent that promotes the reaction. StabiUty of the complex depends on the presence of the ether, and sodium can be Hberated by evaporating the ether or by dilution using an indifferent solvent, such as ethyl ether. A number of ether-type solvents are effective in complex preparation, such as methyl ethyl ether, ethylene glycol dimethyl ether, dioxane, and THF. Trimethyl amine also promotes complex formation. This reaction proceeds with all alkah metals. Other aromatic compounds, eg, diphenyl, anthracene, and phenanthrene, also form sodium complexes (16,20). 

Hydrogen and sodium do not react at room temperature, but at 200—350°C sodium hydride is formed (24,25). The reaction with bulk sodium is slow because of the limited surface available for reaction, but dispersions in hydrocarbons and high surface sodium react more rapidly (7). For the latter, reaction is further accelerated by surface-active agents such as sodium anthracene-9-carboxylate and sodium phenanthrene-9-carboxylate (26—28). 

The reaction of cinnoline 2-oxide with phenylmagnesium bromide gives phenanthrene, trans- and cfs-stilbene, 2,3-diphenyl-l,2-dihydrocinnoline and 2-styrylazobenzene in yields of 1-15%. Analogous results are also obtained from 4-methylcinnoline 2-oxide. 

A more complex reaction model was proposed from the results of a kinetic study of thermal liquefaction of subbituminous coal. Data were obtained over a temperature range of 673 to 743 K (752 to 878°F) at 13.8 MPa (2000 psia) by using two solvents, hydrogenated anthracene oil (HAO), and hydrogenated phenanthrene oil (HPO), at a coal-solvent ratio of 1 15. Results were correlated with the following model ... 

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. 

Reduction of phenanthrene-9,10-dione with HI in acetic acid afforded 9-hydroxyphenanthrene as sole product, while an analogous reaction without acetic acid furnished phenanthrene essentially quantitatively. 

Both phenanthrene and anthracene have a tendency to undergo addition reactions under the eonditions involved in eertain eleetrophilic substitutions. For example, in the nitration of anthracene in the presence of hydrochloric acid, an intermediate addition product can be isolated. This is a result of the relatively close balance in resonance stabilization to be regained by elimination (giving an anthracene ring) or addition (resulting in two benzenoid rings). 

As mentioned above, the scope of the Bucherer reaction is limited. It works with anthracenes and phenanthrenes, but only very few examples with substituted benzenes are known. Naphthylamines can be converted into the corresponding naphthols, and these can then be further converted into primary, secondary or tertiary naphthylamines (transamination). Naphthylamines are of importance for... 

The reaction of ozone with an aromatic compound is considerably slower than the reaction with an alkene. Complete ozonolysis of one mole of benzene with workup under non-oxidative conditions will yield three moles of glyoxal. The selective ozonolysis of particular bonds in appropriate aromatic compounds is used in organic synthesis, for example in the synthesis of a substituted biphenyl 8 from phenanthrene 7 ... 

Phenanthrene-9,10-dione 7 gives 1,4-diazocine 8 on reaction with biphenyl-2,2 -diamine.30... 

Cyclization reactions of unsubstituted phenanthrene-9,10-dicarbonitriles or of 2,7-di-/erf-butyl-phenanthrene-9,10-dicarbonitrile lead to phenanthrenocyanines. 

Recently, Weissman and his colleagues52 showed that the product is paramagnetic indicating that it results from an electron transfer process giving one unpaired electron to the hydrocarbon ion. Furthermore, they demonstrated30 that electron transfer reactions easily proceed in systems containing aromatic" ions and neutral aromatic hydrocarbon molecules, e.g., naphthalene" + phenathrene - naphthalene -j- phenanthrene". 

The red solution of polystyryl carbanions can be kept for days without change in color or viscosity. No changes are observed on addition of further amounts of naphthalene to the red solution. These observations raise some questions. An electron transfer, say for example, between naphthalene" and phenathrene, is a reversible process and it leads eventually to an equilibrium between naphthalene , naphthalene, phenathrene-, and phenanthrene. Is the reaction involving styrene irreversible Now, the initial process of electron transfer from naphthalene to styrene that produces... 

Phenanthrene Diozonide.C14H102O3. Harries and Weiss in 1905 reported that the ozonolysis of phenanthrene in chlf soln produced a crystn, expl diozonide (Refs 2 4). Subsequently, very detailed studies of the ozonolysis reaction of phenanthrene by three different groups of investigators failed to confirm the existence... 

An interesting reaction of dimsyl anion 88 is the methylation of polyaromatic compounds. Thus naphthalene, anthracene, phenanthrene, acridine, quinoline, isoquinoline and phenanthridine were regiospecifically methylated upon treatment with potassium t-butoxide and DMSO in digyme or with sodium hydride in DMSO123-125. Since ca. 50% of D was found to remain in the monomethyl derivative 93 derived from 9-deuteriophenanthrene 92, the mechanistic route shown in Scheme 2 was suggested125. 

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