Phenanthrene Compound

An interesting entry (1992) is the phenanthrene compound halofantrine (Halofan). Earlier clinical trials exhibited 85% or better effectiveness, including some chloroquine-resistant P. falciparum strains. Since the drug does not eliminate exoerythrocytic parasites, the likelihood of relapse in the treatment of P. vivax is significant. 

Riding et al. [39] interpret their results for the 2- and 3-substituted pyridines in terms of the negative group effect of the nitrogen atom in the ring the distance effect of the substituents is considerable. Extension to some bromonaphthalene, anthracene and phenanthrene compounds has been made [74]. The rate coefficients (at 520°K) obtained are 1-bromo-naphthalene, 5.28 x 10 2-bromonaphthalene, 1.19 x 10 9-bromo-anthracene, 2.15 x 10 9-bromophenanthrene, 4.28 x 10 cm mole sec". ... 

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.

The barrier irt phertartthrerte 215 (160 kj mol ) (X = OEt, R = Me) was 30 kJ mol higher thart irt the rtaphthalene analogue 214. Interestingly, the phenanthrene compound underwent spontaneous resolution. Lactonization resulted in racemization. Optically pure atropisomers were employed to prepare optically pure (S,S)- and (R,R)-pyrocoll derivatives 216 and 217. All these atropisomers were screened with success as catalysts in the ethylation of aldehydes by diethylzinc. 

To achieve the above-mentioned objective, the following processes have to be considered (a) formation of H+ at an oxidized anode area (decrease of pH) and OH at a reduced cathode area (increase of pH) (b) dissociation of soluble compounds within an entire length of cell (c) movement of cations and anions into respective electrodes (d) displacement of negatively charged and pH-dependent colloidal particles of clays toward the anode (e) formation of pH-dependent complexes of EDTA-metals and their transport toward the anode (f) electroos-motic transport of inert particles (phenanthrene compound) toward the cathode (g) amphoteric surfactant behavior (in the presence of a variable pH within the cell), formation of micelles, and desorption of phenanthrene (h) displacement of micelles and their transformation and (i) transport and removal of conditioning liquids. 

Phytoalexins from many different plants have been chemically characterized. The phytoalexins include isoflavanoid-derived pterocarpan compounds characteristic of the Leguminosae, sesquiterpenoid compounds characteristic of the Solanaceae, phenanthrene compounds characteristic of the Orchidaceae and acetylenic compounds characteristic of the Compositae. 

In nature, phenanthrene compounds occur in alkaloids, such as morphine. 

Compound 20 is an example of a phenanthrene discotic material that incorporates peripheral chiral units based on lactic acid. Compound 20 only exhibits ferroelectric behaviour when mixed with other chiral phenanthrene compounds. 

Compounds containing olefine links may be oxidised to 1,2-diketones, as in C4H CH CHC Hs -> C HjCO-COC H. Anthracene is readily oxidised to anthraquinone, but phenanthrene is almost unaffected. 

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. 

Fig. 14. Choleic acid inclusion chemistry (a) crystal stmcture of DCA inclusion compound with phenanthrene (b) view along a DCA inclusion helix accommodating DMSO and water guest molecules (oxygen and sulfur atoms and methyl groups are represented by open circles and large and small black...

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). 

In hplc, detection and quantitation have been limited by availabiHty of detectors. Using a uv detector set at 254 nm, the lower limit of detection is 3.5 X 10 g/mL for a compound such as phenanthrene. A fluorescence detector can increase the detectabiHty to 8 x 10 g/mL. The same order of detectabiHty can be achieved using amperometric, electron-capture, or photoioni2ation detectors. 

Among other aromatic compounds that have been tricyanovinylated are phenanthrene (23), o-alkylphenols (24), pyrrole (23), indoles (23,25), 2-meth5lfuran (26), azulenes (26,27), diazocyclopentadiene (28), and a variety of phenyUiydrazones (26). 

Benzene rings can also be fused in angular fashion, as in phenanthrene, chrysene, and picene. These compounds, while reactive toward additions in the center ring, retain most of the resonance energy per electron (REPE) stabilization of benzene and naphthalene. ... 

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 ... 

Another class of compounds is called condensed-ring or fused-ring systems. These structures contain two or more aromatic rings that share a pair of carbon atoms. Examples include naphthalene, anthracene, and phenanthrene, the latter two being isomeric structures. 

Rather similar was the paper [PolG36a] which also derives asymptotic formulae for the number of several kinds of chemical compounds, for example the alcohols and benzene and naphthalene derivatives. Unlike the paper previously mentioned, this one gives proofs of the recursion formulae from which the asymptotic results are derived. A third paper on this topic [PolG36] covers the same sort of ground but ranges more broadly over the chemical compounds. Derivatives of anthracene, pyrene, phenanthrene, and thiophene are considered as well as primary, secondary, and tertiary alcohols, esters, and ketones. In this paper Polya addresses the question of enumerating stereoisomers -- a topic to which we shall return later. 

In another type of aromatic hydrocarbon, two or more benzene rings are fused together. Naphthalene is the simplest compound of this type. Fusion of three benzene rings gives two different isomers, anthracene and phenanthrene. 

Hydrazine reacts with biphenyl-2,2 -dicarbaldehyde (3, R = H). under elimination of nitrogen, to give phenanthrene,17 most probably not via the intermediate formation of a diazocine system. With other 2,2 -diacylbiphenyl compounds the expected dibenzo[[Pg.520]

Phenanthrene, anthracene, and other polynuclear aromatic compounds. 

Photoredox systems involving carbonyl compounds and amines are used in many applications. Carbonyl compounds employed include benzophenone and derivatives, a-diketones [e.g. benzil, cainphoroquinone (85),2W 291 9,10-phenanthrene quinone], and xanthone and coumarin derivatives. The amines are tertiary and must have a-hydrogens [e.g. N,A7-dimethylani 1 ine, Michler s ketone (86)]. The radicals formed are an a-aminoalkyl radical and a ketyl radical. 

Blackley548 measured the rates of deuteration of biphenylene, fluorene, tri-phenylene, and phenanthrene relative to o-xylene as 6.15 5.85 1.08 1.32, which is in very good agreement with the values of 8.80 7.00 - 1.14 which may be deduced from the detritiation data in Table 159, obtained using anhydrous trifluoroacetic acid. Aqueous trifluoroacetic acid (with the addition in some cases of benzene to assist solubility) was used by Rice550, who found that triptycene was 0.1 times as reactive per aromatic ring as o-xylene (cf. 0.13 derivable from Table 159) whereas the compound (XXXI) was 0.9 times as reactive as o-xylene. An exactly comparable measure is not available from Table 158, but dihydroanthracene (XXXII), which is similar, was 0.51 times as reactive as o-xylene and... 

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. 

With this hypothesis, the calculated stability of the 9,10 addition compound of anthracene provides an explanation of the ease of attack of the 9,10 positions for addition. A similar calculation for phenanthrene shows that for this molecule too the 9,10 positions should be most reactive. 

Dihydrovinylphenanthrenes are more reactive than the corresponding vinyl phenanthrenes and undergo Diels-Alder reactions easily. They have been used in the synthesis of polycyclic aromatic compounds and helicenes. Examples of cycloaddition reactions of the 3,4-dihydro-1-vinylphenanthrene (70), [61] 3,4-dihydro-2-vinylphenanthrene (71) [68] and l,2-dihydro-4-vinylphenanthrene (72) [69] are reported in Equation 2.22 and Schemes 2.27 and 2.28. 

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