Phenanthrene, 9 bromo

Peroxides, removal from isoprene, 29,59 removal from isopropyl ether, 22,3 removal from o-tetrabne, 20, 95 Pexphthauc acid, mono-, 20, 70 Petroleum ether, 23,102, 104 Phenacyl chloride, 24, 25, 26 Phenanthrene, 28, 19 purification of, 28, 19 Phenanthrene-9-ai.dehvde, 28, S3 Phenanthrene, 9-bromo-, 28,19 9-Phenanthrenecarboniteile, 28, 7, 34... 

Lund and coworkers [131] pioneered the use of aromatic anion radicals as mediators in a study of the catalytic reduction of bromobenzene by the electrogenerated anion radical of chrysene. Other early investigations involved the catalytic reduction of 1-bromo- and 1-chlorobutane by the anion radicals of trans-stilhene and anthracene [132], of 1-chlorohexane and 6-chloro-l-hexene by the naphthalene anion radical [133], and of 1-chlorooctane by the phenanthrene anion radical [134]. Simonet and coworkers [135] pointed out that a catalytically formed alkyl radical can react with an aromatic anion radical to form an alkylated aromatic hydrocarbon. Additional, comparatively recent work has centered on electron transfer between aromatic anion radicals and l,2-dichloro-l,2-diphenylethane [136], on reductive coupling of tert-butyl bromide with azobenzene, quinoxaline, and anthracene [137], and on the reactions of aromatic anion radicals with substituted benzyl chlorides [138], with... 

Cohare and co-workers reported that aristolactam BU (22) was prepared, following Kupchen s method, by Perkin condensation of 6-bromo-3,4-di-methoxy phenyl acetic acid (119) and o-nitrobenzaldehyde (120) (Scheme 14). The 2-bromo-4,5-dimethoxy-2 -nitro-ds-stilbene-a-carboxylic acid (121) was obtained. The nitro group of 121 was reduced with ferrous sulfate and ammonium hydroxide, and the resulting 2-bromo-4,5-dimethoxy-2 -amino-cw-stilbene-a-carboxylic acid (122) without purification was submitted to the Pschorr phenanthrene synthesis to yield l-bromo-3,4-dimethoxyphen-anthrene-lO-carboxylic acid (123). The phenanthrylamine 124 was prepared from 123 via a Schmidt reaction, and, by treatment with n-butyllithium and CO2, 124, afforded 22 (42). 

To enhance the formation of the 1-substituted helicene Martin 6) introduced in the meta substituted styrylbenzo[c]phenanthrene an additional ortho-bromo substituent. In good yield l-alkyl-4-bromohelicenes (30) were formed, from which the bromo substituent could be withdrawn with LiAlH4 (Scheme 8). 

In order to study the influence of a given chiral group at different positions in the precursor styrylbenzo[c]phenanthrene several carboxy styrylbenzo[c]phenanthrenes were synthesized and esterified with chiral alcohols, and the products were used to prepare hexahelicenes 76 substituted at various positions. The bromo-esters (29) were used as precursors for [6]-helicenes, substituted at position 1. 

In the presence of heptakis(6-bromo-6-deoxy-(3-CD) ((3-CD7Br), Femia and Cline Love observed the room-temperature phosphorescence of phenanthrene and other polynuclear aromatic hydrocarbons in N2-purged N,N-dimethylfol-mamide (DMF)-water mixtures [24], On the other hand, Hamai and Monobe observed room-temperature phosphorescence of 2-chloronaphthalene from a deaerated solution containing a 1 1 complex of 6-iodo-6-deoxy-(3-CD ((3-CDI) and 2-chloronaphthalene [25], This result indicates that even only one iodine atom on the (3-CD rim can accelerate the intersystem crossing rate of 2-chloronaphthalene included in the CD cavity. The room-temperature phosphorescence of 6-bromo-2-naphthol and 3-bromoquinoline was also observed for the complexes with (3-CDI [26],... 

Analytical Properties Resolution of several enantiomers of polycyclic aromatic hydrocarbons, for example, chrysene 5,6-epoxide, dibenz[a,h]anthracene 5,6-epoxide, 7-methyl benz[a]anthracene 5,6-epoxide resolution of barbiturates, mephenytoin, benzodiazepinones, and succinimides direct separation of some mono-ol and diol enantiomers of phenanthrene, benz[a]anthrene, and chrysene ionically bonded to silica gel, this phase provides resolution of enantiomers of c/s-dihydroidiols of unsubstituted and methyl- and bromo-substituted benz[a]anthracene derivatives having hydroxyl groups that adopt quasiequatorial-quasiaxial and quasiaxial-quasiequatorial conformation Reference 31-35... 

The yields obtained on dominating the following amines further illustrate the wide utilitybf hypophosphorous acid 2,4-diethyl-6-bromoaniliae (70%),89 3-nitro-4-aminophenylarsonic acid (45%),90 3-amino-6-bromo-benzoic acid (75%),13 3,3 -dimethylbenzidine (76-82%),80-81 4-amino-7-chlorohydrindone-1 (85%),91 5-methyl-8-aminoquinoline (72%) 84 o-(/3-phenylethyl)-aniline (XXII) (47%).86 In the last case, when ethanol is used dibenzyl is not obtained instead the products are 9,10-dihydro-phenanthrene (co. 50%) and o-(j8-phenylethyl)-phenol (23%).66... 

Carbon-halogen bond cleavage in aryl halides is believed to involve initial excitation into an upper singlet state that is stable with respect to cleavage, followed by intersystem crossing to an upper triplet state that is either dissociative itself or can cross to an upper dissociative (a, a ) triplet [65-67]. The two-color approach has been used to demonstrate directly that excitation to an upper triplet state results in carbon-halogen cleavage. For example, in 2-bromonaphthalene (81) and 9-bromo-phenanthrene (82) [68], promotion of Tj to an upper triplet by dye laser excitation... 

For the preparation of chlorides or bromides, the diazonium salt is decomposed with a solution of cuprous chloride or bromide in the corresponding halogen acid (Sandmeyer reaction). It is possible to prepare the aryl bromide from the diazonium chloride or sulfate. A variation Involves the use of copper powder and a mineral acid for the decomposition step (Gattermann reaction). Both procedures are illustrated by the syntheses of the isomeric bromotoluenes and chlorotoluenes. The usual conditions of the Sandmeyer reaction fail in the preparation of the chloro- and bromo-phenanthrenes. However, these compounds can be successfully obtained by the interaction of the diazonium compound with mercuric and potassium halides (Schwechten procedure). Another procedure for formation of aryl bromides involves treatment of the amine hydrobromide with nitrogen trioxide in the presence of excess 40% hydro-bromic acid. The Intermediate diazonium perbromide is then decomposed by heat. ... 

The success of the reaction depends largely on the use of finely ground aluminum chloride and freshly prepared cyanogen bromide. Aromatic hydrocarbons—benzene, toluene, anthracene, and acenaphthene—and phenolic ethers respond favorably. However, phenanthrene gives none of the anticipated nitrile. As might be expected, a by-product is the aryl bromide. Indeed, thiophene and furan are converted largely to the a-bromo derivatives. 

With azines the situation is varied. In the radical cations of pyridine and diazines the semi-occupied orbital is largely confined to the nn orbital(s) (see Scheme 2, structure 2), while the radical cation is of the n type with monoazanaphthalenes, -phenanthrenes and -anthracenes. The situation might change with substitution. As an example, alkylpyridine radical cations are of the n type, like the parent compound, whereas for the 2,5-dimethyl, 2-chloro, and 2-bromo derivatives the structure is of the n type [13]. Likewise, with benzo[c]cinnoline the parent compound and its alkyl derivatives give an n radical cation, but with some dimethoxy derivatives a n structure is found [14] and a switch from n to 7t structure occurs also in passing from 1,2,4,5-tetrazine to its 3,6-diamino derivatives [15]. 

In a study of the reaetion between alkyl halides and the electrogenerated naphthalene radical anion, Sease and Reed [297] observed that only alkyl chlorides, such as 1-chloro-hexane and 6-chloro-l-hexene, are catalytically reduced 1-chlorohexane gives only n-hex-ane, whereas 6-chloro-l-hexene affords methylcyclopentane and 1-hexene. In an earlier paper [296], the reactions of 1-bromo- and 1-chlorobutane with the electrogenerated radical anions of rmn -stilbene and anthracene in DMSO were examined. Britton and Fry [298] elucidated the kinetics of the electron-transfer reaction between 1-chlorooctane and the phenanthrene radieal anion in DMF. 

The procedure described for the preparation of 9-bromo-phenanthrene is an adaptation of that described by Henstock, who effected the bromination at various temperatures and in different solvents but gave little experimental detail. Other methods of preparation involve the formation and isolation of phenanthrene dibromide and its subsequent conversion to 9-bromophenanthrene by heating. 

The fact that both phenanthrene and phenanthrene dibromide react at the same rate in the presence of iodine and bromine to give 9-bromo-phenanthrene23 suggests that the same intermediates are involved in... 

Phenanthrene-9-carbonitrile, prepared by bromination of phenanthrene to the 9-bromo derivative54 and its transformation by cuprous cyanide in dimethylform-amidess, served as starting material for the needed phenanthrene-9-acetonitrile (86). By the same sequence of steps as when converting phenanthrene- 1-carbonitrile (72a) to (81) the 9-carbonitrile was converted to (86), giving an overall yield of 60%. The standard procedure leads very smoothly to the triphenylenes (57) ... 

One pathway to benzo(c)phenanthrene by the cyclization-elimination method has been outlined already (Section III., B. 2.) and another we will see later. A synthesis by benzannelation should start with phenanthrene-4-acetonitrile or with phenanthrene 3-acetonitrile (88) as the one component. For steric reasons the preparation of the first has only poor chances, but (88) is readily available 3-methylphenanthrene, mp. 62—63°56), obtained by hydrolysis and decarboxylation from the nitrile (72 b) (Section III., C. 3.) in an overall yield of 92% was side-chain brominated by N-bromo-succinimide in CC14, and the 3 bromomethylphenanthrene, mp. 116—117° (67%), converted to (88), mp. 82-83° (91%). 

Hofmann degradation of N-methylthebenine dimethyl ether methiodide or methomethylsulphate, which result from the complete methylation of thebenine, affords 3 4 8-trimethoxy-5-vinylphenan-threne [vn], the 4-methoxyl group of which is so readily hydrolysed that boiling with acetic acid or alcoholic hydrogen chloride results in formation of methebenol and bromination in formation of bromo-methebenol [8], 3 4 8-Trimethoxy-5-vinylphenanthrene can be reduced to 3 4 8-trimethoxy-5-ethylphenanthrene, identical with a specimen prepared from 2-nitroveratric aldehyde and 2-methoxy-5-ethylphenyl-acetic acid by the Pschorr phenanthrene synthesis [11]. 

Nitroveratric aldehyde and 3 4-dimethoxyphenylacetic acid were condensed to give the acid [xv, R = H]. Reduction and Pschorr phenanthrene ring-closure of this gave two tetramethoxyphenanthrene carboxylic acids one of these, also accessible from the bromo-acid [iv, R = Br], must be the 3 4 5 6-isomer [v] and the other the 3 4 6 7-isomer [yi]. The latter on decarboxylation afforded dimethylsinomenol [u, R = Me]. 

Diacetoxy-3-methoxyphenanthrene and triacetylisothebenine are obtained by the acetolysis of sinomenine hydrate and the 1-bromo-derivatives of these can be prepared in the same way from 1-bromosinomeninone. Catalytic reduction of both triacetylisothebenine and its 1-bromo-derivative affords triacetyl-9 10-dihydroisothebenine [55], believed by Schopf, Pfeiffer, and Hirsch [64] to be triacetylisothebenine when the same sequence of reactions was carried out on (—)-l-bromo-sinomeninone. /sothebenine is probably 4 6-dihydroxy-3-methoxy-5-(/3-methylaminoethyl)-phenanthrene [lxxxh], or the 4 7-dihydroxy-isomer [64], On heating with sodium hydroxide and methyl alcohol at 80° C., 1-bromotriacetyKsothebenine yields a compound C2oH2004NBr in 7 per cent, yield this is probably 1 -bromo-N-acetylisothebenine [55] (see also Chap. XXV). 

Methoxy-4 6-diacetoxyphenanthrene [nr] is formed when codeinone [lii] [68] and sinomenine hydrate [un] [69] axe heated with acetic anhydride and sodium acetate a second product in the degradation of [lih] is triacetyh sothebenine [liv ]. The 1-bromo-derivative can be obtained in like manner from the antipodes of 1-bromosino-meninone [69-70] and reduced catalytically to [li]. Hydrolysis of [li] affords the corresponding 4 6-dihydroxy-compound, which results from heating codeinone methiodide with ethanol at 160° C. [71] both compounds have been identified by conversion to 3 4 6-trimethoxy-phenanthrene [68],... 

One of the more common cyclization processes of phenols is the formation of the phenanthrene skeleton. These processes utilize the fission of a C—X bond to yield aryl radicals that then attack a neighbouring aryl group. Typical of this is the bromo or iodo derivative of 208 that cyclizes to afford the lactam 209 in moderate yields . The... 

Cyclopropanes containing a C-Co a bond have been obtained by treating bromocyclopropanes with sodium [bis(dimethylglyoximato)](pyridine)cobalt. The yields were very low (< 7%) when the substrates were l,l-dibromo-la,9b-dihydrocyclopropa[/]phenanthrene and a tt-l-bromo-la,9b-dihydrocyclopropa[/]phenanthrene, but when 1-bromo-l-methyl-2,2-diphenylcyclo-propane was reacted with [bis(dimethylglyoximato)](pyridine)cobalt(I), substitution predominated and [bis(dimethylglyoximato)](l-methyl-2,2-diphenylcyclopropyl)(pyridine)cobalt was formed in 60% yield. 

A more recent variation of the general procedure described in the previous section involves the use of adducts of l-bromo-2-chlorocyclopropene as substrates for the double elimination reaction.Thus, l/f-cyclopropa[6]phenanthrene (4) was obtained in 89% yield in the final step of a sequence that included cycloaddition to diene 1 followed by aromatization. ... 

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