Phenanthrene 9 aldehyde

Submitted by Clinton A. Dohnfeld and George H. Coleman. Checked by Robert E. Carnahan and Homer Adkins. 

A dry 5-1. three-necked flask is provided with a stirrer (Note 1), a nitrogen inlet tube, a 500-ml. Pyrex separatory funnel, and a large Allihn reflux condenser. To the upper end of the condenser are attached an outlet tube and a 1-1. separatory funnel. Both separatory funnels and the outlet tube are provided with 

The mixture is allowed to cool until refluxing ceases, and 296.4 g. (2 moles) of ethyl orthoformate (Note 5) is added from the lower separatory funnel over a period of about 30 minutes. The mixture is then refluxed gently for 6 hours. 

The reaction mixture is cooled with stirring in an ice bath, and 11. of cold 10% hydrochloric acid (Note 6) is added from the separatory funnel the acid is added dropwise at first and more rapidly after the reaction subsides. The benzene-ether layer is separated from the aqueous layer and concentrated under reduced pressure in a 5-1. round-bottomed flask on a steam bath. One liter of 25% sulfuric acid is added to the residue, and the mixture is refluxed gently for 12 hours. 

The mixture is then cooled in an ice bath, the acid is decanted, and the residue is washed twice by decantation with water. The residue is dissolved in 1 1. of benzene in the same flask, and 1.5 1. of water and 1.2 kg. of sodium bisulfite are added. The flask is fitted with a stirrer, and the mixture is stirred vigorously overnight. The mixture is filtered through an 8-in. Buchner funnel, and the bisulfite addition product is washed on the funnel with 500 ml. of benzene. 

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Phenanthrene-9-aldehyde [4707-71-5] from EtOH and sublimed at 95-98°/0.07mm. 

Phenanthrene-9-aldehyde [4707-71-5] M 206.3, m 102.2-103°/12mm. Crystd from EtOH and sublimed at 95-98°/0.07mm. " ... 

Crude bromophenanthrene prepared by the bromination of technical (90%) phenanthrene and purified by distillation only was used by the submitters in this preparation. The an-thracene-9-aldehyde, which may be formed from the anthracene present as an impurity in 90% phenanthrene, does not form a sodimn bisulfite addition product and so will not contaminate the phenanthrene-9-aldehyde. The checkers used 9-bromophe-nanthrene, m.p. 54-56° (p. 20), exclusively, but without any advantage in yield. The submitters report yields of 55-60% from pure 9-bromophenanthrene. 

Phenanthrene-9-aldehyde has been obtained by the Sonn and Muller synthesis from 9-phenanthroyl chloride, by the Rosen-mund reduction of 9-phenanthroyl chloride, by the Gatterman... 

The preparation of phenanthrene-9-aldehyde starts with crude 9-bromophenan-threne obtained by bromination of technical phenanthrene (90%) and purified only by distillation (m.p. 54-56° crystalhzation gives pure material, m.p. 65-66°). The magnesium (50.3 g.) is placed in a 5-1. flask provided with a stirrer, a 500-ml. separatory funnel, a nitrogen-inlet tube, and a large reflux condenser fitted at the top with a 1-1. separatory funnel. The crude bromophenanthrene (514 g.) is vMgBr CHlOCjHs) CHO... 

Besides the aromatic hydrocarbons the Ea of a number of aromatic carbonyl compounds have been determined using the ECD. These include substituted acetophenones, benzaldehydes, benzophenones, benzoates, phthalates, acetonaphthone, naphthaldehydes, and anthracene and phenanthrene aldehydes. Like the aromatic hydrocarbons, the majority of these compounds only undergo nondissociative... 

The chloromethylation can be generally employed in aromatic chemistry benzene, naphthaline, anthracene, phenanthrene, biphenyls and many derivatives thereof are appropriate substrates. The benzylic chlorides thus obtained can be further transformed, for example to aromatic aldehydes. Ketones like benzophe-none are not reactive enough. In contrast phenols are so reactive that polymeric products are obtained. ... 

Many polycyclic aromatic amines and aldehydes are commercially available, but their supply is very limited. Preparation of these starting materials is necessary for studying the (3-lactam formation reaction [93]. Nitro compounds are the precursors for the amines. An important task was to prepare polycyclic aromatic nitro compounds, particularly those of chrysene, phenanthrene, pyrene, and dibenzofluorene in good yield. Nitration of these hydrocarbons with concentrated nitric acid in sulfuric acid is a widely used reaction for this purpose. Our research culminated in facile synthesis of polyaromatic nitro derivative 9 starting from polyaromatic hydrocarbons (PAHs) 8 through the use of bismuth nitrate impregnated with clay (Scheme 1) ([94, 95] for some examples of bismuth nitrate-catalyzed reactions... 

Phenanthrene has also a reactive 9,10-double bond, in agreement with the Clar structure having two aromatic sextets and a C=C fixed double bond in the median ring. On co-ozonolysis with formaldehyde, acetyl cyanide, or benzoyl cyanide, phenanthrene reacted accordingly, affording an aldehydic ozonide 112, which in a separate co-ozonolysis with vinyl acetate that produced formaldehyde oxide (H2C-0-0) gave rise to a diozonide 113 (Scheme 35 and Table 14). 

In the case of pyrene, there are two sextets and two fixed double bonds similar to the phenanthrenic double bond. In agreement with this argument and with the result for phenanthrene, co-ozonolysis of pyrene with formaldehyde or acetyl cyanide afforded the expected normal ozonide 114 and the cross-ozonide 115 with an aldehydic group. In a separate co-ozonolysis of 115 with vinyl acetate, diozonides 116 were prepared. No cross-ozonide was obtained in the presence of benzoyl cyanide, which afforded only the normal mono-ozonide 114 (Scheme 36 and Table 15). 

The final polycyclic aromatic hydrocarbon that was investigated <2000EJ0335> is benzo[fixed double bond like phenanthrene. Its cross-ozonolysis with formaldehyde gave none of the normal ozonide 120, but mainly the aldehydic ozonide 117. At room temperature, a substantial amount of opening of the ozonide ring occurred with the formation of the acid aldehyde 121. Both products 117 and 121 could be stabilized by treatment with O-methylhydroxylamine, yielding products 118 and 122, respectively. The separate co-ozonolysis of compound 117 with vinyl acetate afforded the diozonide 119 (Scheme 37 and Table 16). The cross-ozonolysis with acetyl cyanide followed by treatment of the crude reaction mixture with O-methylhydroxylamine yielded the O-methyloxime of the cross-product. Cross-ozonolysis with benzoyl cyanide was not successful, and only the normal mono-ozonide 120 was formed. 

Oxadithiocines 29 are unstable, acid-sensitive compounds, obtained by photolysis of 4,8,10-trithiadibenzo-[cd,ij]-3ira ene 8-oxides 28 (see Section 14.08.8.2.5). Their additional photolysis results in the corresponding aldehydes or ketones and 4,8,9-trithiacyclopenta[rf7/]phenanthrene 30 as a major rearrangement product (Scheme 3 <1996CL655>). 

Phenanthrene synthesis. A new phenanthrene synthesis employs the nickel(O)-catalyzed condensation of the imine 1 with 2 to give, after hydrolysis, the aldehyde 3. This product was converted in several steps to the phenanthrene 4, which is a key... 

Ozonolysis of the phenanthrene alkaloid 206, easily obtained by base treatment followed by acetylation of the aporphine magnoflorine, gives dialdehyde 207 (Scheme 5). Aldehyde oxidation with silver oxide, followed by hydrolysis... 

Many completely aromatic polynuclear hydrocarbons are readily formed by cyclization of aryl-substituted aldehydes, ketones, or related compounds. The simplest case is the formation of naphthalene by refluxing (fi-styrylacetaldehyde, C HsCH = CHCH2CHO, with hydrobromic acid-acetic acid mixture. " The ring closure has found extensive use in the synthesis of 9-alkyl- and 9 aryl-anthracenes and phenanthrenes. " ... 

The reaction of ethyl orthoformate and Grignard reagents gives acetals which are hydrolyzed readily by dilute acid to aldehydes. This method has been employed extensively for the preparation of aliphatic and aromatic aldehydes. A study of the optimum conditions has been made, using the conversion of bromobenzene to benzaldehyde as a model synthesis (90%), Comparative studies of various aldehyde syntheses that employ Grignard reagents (methods 154, 166, and 167) show that this one is the most practical however, the possibility of a sudden exothermic reaction limits the size of the run. Longer reaction times at room or reflux tempjerature help overcome this difficulty. Examples of the better preparative procedures are found in those for -hexaldehyde (50%), p-tolualdehyde (TS ), " and phenanthrene-S>-aldehyde (42%)." ... 

The breakdown of the benzene ring to aldehydes is extremely rare and has been achieved only by ozone. A historical and classical example is the disintegration of o-xylene to a mixture of glyoxal, methyl glyoxal, and diacetyl (butanedione) in the predicted ratios [104]. From the preparative point of view, the conversion of phenanthrene into 0,0 -diformyl-biphenyl (diphenaldehyde) [1123] or o-formylbiphenyl-o -carboxylic (diphenaldehydic) acid [1124] is more important (equation 154). 

Pathway for Reduction. The alkaline oxidation of alcohols and glycols is thought to involve hydride transfer with the intermediate formation of the corresponding aldehydes (12, 20) (Equation 3) where Ar equals naphthalene, phenanthrene, etc. 

Under the Schmidt reaction conditions, the lactol (152) of 4-formyl-5-phenanthroic acid gives 1 -aza-pyren-2(lW)-one (153) and phenathrene-4,5-dicarboximide (154)." The compound (153) may be formed by attack of hydrazoic acid at the latent aldehyde site in preference to the carboxy site (see Section 4.4.4.2). Phenanthrene-4,5-dicarboxylic acid (155), obtained by oxidation of (152), similarly affords... 

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. 

Photocleavage of benzyl-S bonds appears to proceed neither by an electron transfer pathway nor with participation of an exciplex. A meta effect seems to operate in these reactions as evidenced by the influence of 3-methoxy and of 3-cyano substituents on the efficiency of the cleavage process. Photolysis of 1,2-bis(phenoxymethyl)-, l,2-bis(phenylthiomethyl)-, and l,2-bis(phenylseleno-methyl)benzene induces a two-photon process to give o-quinonedimethane, which in the presence of dienophiles undergoes a cycloaddition reaction, and 4,8,10-trithiadibenzo[cd,ij]azulene 8-oxides gives the corresponding aldehydes and ketones together with 4,8,9-trithiacyclopenta[def]phenanthrene. The two... 

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