Phenalene derivatives

A modification of these reactions is the thionation of j8-diketones and derivatives. Products are obtained by thionation (i.e. treatment with phosphorus pentasulfide) which give 1,2-dithiolylium salts (4) by reaction with acid (65LA(682)188), most successfully for aryl derivatives (70BSF1918). An interesting phenalene derivative (136) was prepared from 9-ethoxyphenalenone (135) (78JA7629). 

Fig. 5. Combined Br nsted plot including the phenalene derivatives (black squares).

Heteroeyeles structurally based on the phenalene ring system form an interesting elass, frequently possessing distinetive eolours. With nitrogen as the central atom we have the unstable 9b-azaphenalene (24), whieh has only fairly reeently been prepared and is still comparatively little studied (76JCS(Pl)34l). The cyclazine nomenclature is commonly applied to this and related compounds thus, (24) is (3.3.3)cyclazine. With further aza substitution, in positions alternant to the central atom, their stability increases the heptaazaphenalene (25) is (thermally) a very inert compound, derivatives of which, e.g. the triamine, have been known since the early days of organic chemistry (see Chapter 2.20). 

The orbital coefficients for the MO of energy a for the phenalenyl system described in Fig. 9.7 are as shown below. Predict the general appearance of the NMR spectra of the anion and cation derived from phenalene. 

In another study, the arenium ions of protonation and the two-electron oxidation dications derived from BaP and three of its nonalternant isomers, namely, azu-leno[5,6,7-c phenalene 69 (a strong carcinogen reported to be as potent as BaP), azuleno[l,2,3-cJ phenalene 70 (a strong mutagen/weak carcinogen), and... 

Figure 6. First derivative electron spin resonance spectrum of radical anion formed spontaneously from phenalene in dimethyl sulfoxide (80% )-tert-butyl...

A third way to fluoranthenes (126) should be opened by the thermal cyclization of the long-known, stable, colored enaminofulvenes of fluorenes24 e.g. (125), which are isomeric with the corresponding derivatives (104) of phenalene ... 

Also a methyl and a phenyl derivative of (168) were prepared analogously, the related l,2-dihydroazuleno(5,6,7-c,d)cyclopenta(g,h)phenalene (169)65 was also obtained in moderate yield using the l,2-dihydro-5H-cyclopenta(c,d)phenalene (115). Both hydrocarbons, (168) and (169) are strongly suspected of cancerogenity77. ... 

Jellimann. C.. Mathe-Allainmat. M.. Andrieux, J., Kloubert, S., Boutin, J.A., Nicolas, J.-P., Bennejean, C.. Delagrange, P., and Langlois. M., Synthesis of phenalene and acenaphthene derivatives as new conformationally restricted ligands for melatonin receptors, J. Med. Chem., 43, 4051, 2000. 

The H-NMR and C-NMR spectra of both the anion and cation derived from phenalene have been observed. The HMO pattern for phenalene is given below. 

The naphthocyclopropane derivative of Scheme 14.1 not only was found to give phenalene, but it underwent bridgehead double inversion upon heating. These reactions most reasonably occur via cleavage of the more substituted cyclopropane bond followed by a vicinal hydrogen shift. Subsequently, it was shown that the reactions were not affected by the presence of oxygen which indicates that the biradical is probably in its singlet state. ... 

All the phenalenones so far isolated from plants are derivatives of 9-phenyl-lH-phenalen-1-one (44). All the related compounds occurring with them may be regarded as metabolic oxidation products phenyl-naphthalides, phenylnaphthalic anhydrides, quinonemethides derived from oxa- and aza-phenalenones, derivatives of lH-naphtho[2,l,8- wia]-xanthen-l-one (45) and a phenalenone dimer. 

For = 3 it is inferred from Table 3 jjjjj (3) = 13 + 5 = 18. In addition to the smallest triple coronoid (with h = 18) derived from phenalene according to the algorithm one... 

Fig. 15.4 Plots of the initial phosphorescence of singlet oxygen at 1,270 nm as a function of laser Intensity for l//-phenalen-l-one and an oligothiophene derivative in air-saturated toluene solutions at 293 K. Reproduced with permission from Ref. [95], Copyright 2006, the American Chemical Society...

New benchrotrene derivatives have been prepared by reactions of [Cr(CO)s], etc., with oestrone and related steroids, phenalene, 2,6,15,19-tetrathia-[7.7]paracyclophane, PhjAs, and diphenic acid and related compounds. Ring-substituted derivatives of [( benzaldehyde)Cr(CO)3] have been resolved into enantiomeric forms. Reactions of carbene complexes of the type [(OQs-CrC(OMe)Ar] with alkynes have afforded derivatives of [(jy -naphthalene)-Cr(CO>3] (see Vol. 8, refs. 393, 394). 

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