Radical Anion of Azuleno[5.6.7-cd]phenalene,a Failure of the Simple HMO Model

Hyperfine proton coupling constants are reported for the radical anions of azuleno-[5.6.7-cd]phenalene (I), 6-phenylazulene (II) and the corresponding 1,3-dideuterio-derivatives (I-d₂ and II-d₂). The singly occupied orbitals of both I^? and II^? are found to be symmetric with respect to the mirror plane perpendicular to the plane of the molecule. In the case of I, surprisingly, such an orbital corresponds not to the first, but to the second lowest antibonding HMO. A correlation diagram for the relevant orbitals of I and II indicates that the correct energy order in the HMO model of I can be achieved by a decrease in the absolute value of the parameter β_μν for the bonds 4a–5, 6–6a, 9a–10 and 11–11a.     

Synthesis of 6H-Naphtho[1,2,3-cd]indol-6-ones

S,S-Dimethyl-and S-methyl-S-phenyl-N-(9,10-anthraquinon-1-yl)sulfoximides are converted into 6H-naphtho[1,2,3-cd]indol-6-ones on heating in polar aprotic solvents.     

Second-derivative constant-wavelength synchronous scan spectrofluorimetry for determination of benzo[b]fluoranthene, benzo[a]pyrene and indeno[1,2,3-cd]pyrene in drinking water

The use of derivative constant-wavelength synchronous scan fluorimetry is reported for the determination of three polycyclic aromatic hydrocarbon pollutants in drinking water (linearity range 0.4-4 mug 1(-1)). The limits of detection (LD) and quantification (LQ) (mug 1(-1)) are 0.01 and 0.07 for benzo[b]fluoranthene, 0.03 and 0.12 for benzo[a]pyrene and 0.19 and 0.57 for indeno[1,2,3-cd]pyrene in the presence of three other pollutants, benzo[k]fluoranthene, benzo[ghi]perylene and fluoranthene. The precision (RSD /= 85%) were satisfactory.     

A novel route from triptycenes to a dibenzo(Hafner's hydrocarbon), benz[a]indeno[1,2,3-cd]azulene

Triptycenes carrying a leaving group at one of the bridgehead carbons afforded the title compound in good to moderate yields when irradiated with a low-pressure Hg lamp. The tropylium ion and the strong CT-complexes of the hydrocarbon were prepared.     

Synthesis of substituted 1,4-diazepino[5,6,7-kl]acridines and imidazo[4,5,1-de][1,4]diazepino[5,6,7-mn]acridines

The synthesis of some substituted ll-methoxy-7-nitro-4H,8H-2,3-dihydro-1,4-diazepino[5,6,7-kl]acridines 4 with more diversified chains at position 4 is described. A convenient method for transformation of these compounds into the corresponding 4-substituted 12-methoxy-4H-2,3-dihydroimidazo[4,5,1-de][1,4]diazepino-[5,6,7-mn]acridine (5) is reported.