Phenanthrene complexes

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). 

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 ... 

Phenanthrene and anthracene both react preferentially in the center ring. This behavior is expected from simple resonance considerations. The c-complexes that result from substitution in the center ring have two intact benzene rings. The total resonance stabilization of these intermediates is larger than that of the naphthalene system that results if substitution occurs at one of the terminal rings. ... 

Rigid diphosphines have been used to enforce n-ans-geometries thus with the phenanthrene-derived diphosphine (Figure 3.49, R = Et) the complexes PdLCb and PtLCl2 have closely similar geometries (Pd-P 2.307 A, Pd-Cl 2.306 A, P-Pd-P 177.4° Pt-P 2.293 A, Pt-Cl 2.304 A, P-Pt-P 177.1°)... 

The series M(PP)C1 (PP = 2,ll-bis(diphenylphosphinomethyl)benzo[c]-phenanthrene M = Cu, Ag, Au) is interesting in showing group trends (Table 4.7) where the silver and copper complexes have trigonal coordination and the gold member is linear [50]. 

It is thought that the chlorination proceeds through a ir-com-plex between cupric chloride and anthracene, and that this complex then undergoes homolytic dissociation. Hence aromatic rings subject to attack by chlorine atoms can be chlorinated in this way. Thus one can convert pyrene to 1-chloropyrene (90% yield), but phenanthrene is not chlorinated. Analogous procedures using cupric bromide lead to 9-bromoanthracene (99% yield) and 1-bromopyrene (94% yield).7... 

The complexes precipitate immediately on mixing 1 1 complexes (n = 1) are prepared from arenes such as benzene, biphenyl, naphthalene, acenaphthalene, fluorene, phenanthrene, anthracene and m-dinitrobenzene. These complexes contain a complex Hg(I) cation with the arene v coordinated to one Hg as in III ... 

Experiments using marine sediment slurries have examined the effect of pre-exposure to various aromatic hydrocarbons on the rate of subsequent degradation of the same, or other hydrocarbons. The results clearly illustrated the complexity of the selection process for example, whereas pre-exposure to benzene, naphthalene, anthracene, or phenanthrene... 

Photochemical osmylation. The irradiation of the charge-transfer bands (Fig. 13) of the EDA complex of 0s04 with various benzenes, naphthalenes, anthracenes, and phenanthrene yields the same osmylated adducts as obtained in the thermal reactions. For example, irradiation of the purple solution of anthracene and 0s04 in dichloromethane at k > 480 nm yields the same 2 1 adduct (B) together with its syn isomer as the sole products, i.e.,... 

Theng BKG, Newman RH, Whitton JS (1998) Characterization of an alkylammonium-montmorillonite-phenanthrene intercalation complex by carbon-13 nuclear magnetic resonance spectroscopy. Clay Miner 33 221-229... 

Figure 3.49 The (ra .v-complexes of a phenanthrene-derived diphosphine ligand (M = Pd, Pt).

The complexes Cr(CO)3L, with L = phenanthrene, naphthalene, or anthracene, are more active for diene hydrogenation than with L = substituted benzenes (see also Section VIII), and this is attributed to an easier displacement of the arene by the diene substrate, the phenanthrene type being asymmetrically bonded, having two longer and more readily cleaved chromium-carbon bonds (198, 199). 

Photolysis ofbenzylchlorodiazirine (3) in the presence of tetramethylethylene (TME) is known to produce ( )- and (Z)-/l-chlorostyrene (4) and the cyclopropane (5). Plots of [5]/[4] vs [TME] are curved, consistent with the existence of two pathways for the formation of the alkenes (4). Benzylchlorocarbene (BnClC ) was generated by laser flash photolysis of the phenanthrene (6) in the presence of TME. In this case, plots of [5]/[4] vs [TME] are linear, mling out the possibility that the second pathway to the alkenes (4) involves reaction of a carbene-alkene complex. Time-resolved IR spectroscopy revealed that diazirine (3) rearranges to the corresponding diazo compound, but this process is too inefficient to account for the curvatures. It is proposed that the second pathway to alkene formation involves the excited state of the diazirine. 

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