Dibenzo naphthacene

Figure 5.12 Polyaromatic hydrocarbon species (1) phenanthrene, (2) anthracene, (3) pyrene, (4) benz[o]anthracene, (5) chrysene, (6) naphthacene, (7) benzo[c]phenanthrene, (8) benzo[ghi] fluoranthene, (9) dibenzo[c,g]phenanthrene, (10) benzo[g/ ]perylene, (11) triphenylene, (12) o-terphenyl, (13) m-terphenyl, (14) p-terphenyl, (15) benzo[o]pyrene, (16) tetrabenzonaphthalene, (17) phenanthro[3,4-c]phenanthrene, (18) coronene...

The structures of the radical anion of dibenzo[a,c]naphthacene (135) and the corresponding radical cation were investigated by ESR and proton-ENDOR spectroscopies. ... 

Especially good agreements between the Clar picture and ef are observed in the case of fully benzenoid systems [39]. (A benzenoid hydrocarbon is said to be fully benzenoid if it has a Clar formula without double bonds.) Two typical examples are provided by triphenylene (4) and dibenzo[fg,op]naphthacene (5). 

Figure 26. Clar aromatic sextet formula of dibenzo[/, op]naphthacene...

The reaction between Fe3(CO)i2 and naphthacene lead to a new type of binuclear complex (CieHi2)[Fe2(CO)e] for which structure (XXIII) was proposed 22). The condensed aromatics acridine, phenazine, 4-benz[c]acridine, 5-benzo[a]phenazine, and dibenzo[a,c]phenazine were shown to react with Fe3(CO)ia to give complexes in which an Fe(CO)3 moiety is bound to a terminal ring directly adjacent to the heterocycle ring 22). 

In principle, one can represent the dibenzo[a,c]naphthacene (20) as a combination of anthracene and phenanthrene (23). In the same sense, di-benzo[a,c]phenazine (15) and tribenzo[a,c,i]phenazine (12) can be considered as quinoxaline-phenanthrene and benzo[g]quinoxaline-phenanthrene, respectively (Figure 9). The XH spectra of dianions 12, 15, and 20 are shown... 

Figure 11. 1H NMR spectrum (300 MHz) of the dibenzo[a,c naphthacene dianion (20) as a disodium salt in THF-d8 at room temperature (23). S indicates a solvent signal. (Reproduced from reference 23. Copyright 1984 American...

Dibenzo[ z, i]fluorene Dibenzo [a,j] naphthacene Dibenzo[ i, r] naphthacene Dibenzo 1/, 0/ ] naphthacene Dibenzopyrene Fluoranthene Fluoranthene, 2-methyl-Fluoranthene, 3-methyl-... 

In Fig. 9.21, we show how a pair of peri-condensed benzenoid with identical numeric codes can be recovered from their perimeter codes. As an illustrative example, we selected numeric code 5 5 2 2 5 5 which is identified to belong to a pair of Kekule structures of dibenzo[, op]naphthacene. 

It should be noted that dibenzo /g,op]naphthacene has 20 Kekule structures. Besides the pair of its Kekule structures shown in Fig. 9.21, it possesses two more pairs of Kekule structures with identical numeric codes (Vukicevic et al. 2004). 

Dibenzo[/"g,op]naphthacene 60 was obtained by double direct arylation of 1,3-bis(2-bromophenyl)-2-(4-methoxyphenyl) benzene 59 (Scheme 22.14) [29]. Considering that tetracene derivatives are a class of attractive PAHs as semiconducting materials [30], this approach may contribute to the progress of organic transistor materials based on a fused tetracenes and their heterole analogs. 

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