Synthesis of Hexabenzo[a,cd,f,j,lm,o]perylene

Hexabenzo[a,cd,f,j,lm,o]perylene (HBP), an undecacyclic condensed polycyclic aromatic hydrocarbon with two severely crowded fjord regions, was synthesized by Clar's method; the starting material 8H-benzo[fg]-naphthacene-8-one was newly prepared by the glycerol condensation of 5,12-dihydro-naphthacene-5,12-dione. ¹H and ¹³C NMR spectra of HBP were measured and the chemical shifts were completely assigned. Absorption and fluorescence spectra of HBP were also measured and the effects of nonplanarity on its spectroscopic properties was discussed.     

IDENTIFICATION OF THE C30H16 POLYCYCLIC AROMATIC HYDROCARBON BENZO[cd]NAPHTHO[1,2,3-lm]PERYLENE AS A PRODUCT OF THE SUPERCRITICAL PYROLYSIS OF A SYNTHETIC JET FUEL

Using high-pressure liquid chromatography (HPLC) with ultraviolet-visible (UV) diode-array and mass spectrometric detection, we have analyzed the products of a Fischer-Tropsch synthetic jet fuel pyrolyzed, under supercritical conditions, at 710°C and 42 atm. An eight-ring polycyclic aromatic hydrocarbon, benzo[cd]naphtho[1,2,3-lm]perylene, has been unequivocally identified among the product components by its characteristic ultraviolet-visible absorbance spectrum. First, the unknown product component's HPLC elution behavior and UV absorbance characteristics indicated that it was a planar benzologue of dibenzo[cd,lm]perylene, having a high length-to-breadth ratio. Next, the mass spectrum established the isomer family of the unknown compound as C₃₀H₁₆. The UV absorption spectrum was then progressively analyzed with different solvents to achieve the final identification of benzo[cd]naphtho[1,2,3-lm]perylene. Benzo[cd]naphtho[1,2,3-lm]perylene has never before been reported as a product in any combustion or pyrolysis study.     

LEAVES OF NERIUM OLEANDER L. AS BIOACCUMULATORS OF POLYCYCLIC AROMATIC HYDROCARBONS (PAH) IN THE AIR OF PALERMO (ITALY): EXTRACTION AND GC-MS ANALYSIS,DISTRIBUTION AND SOURCES

Polycyclic Aromatic Hydrocarbons (PAH) were determined in the leaves of Nerium oleander L. an evergreen plant that occurs widely in both urban and rural areas, to monitor the degree of pollution in the urban area of Palermo (Italy) compared to remote areas. Twenty sites (urban roadside, urban, urban park, suburban and rural) in and around Palermo city were investigated.

The purpose of this research was to investigate concentration levels and distribution patterns and relate them to possible sources. Analysis of 19 PAH was performed by gas chromatography/mass spectrometry (GCMS) using selected ion monitoring (SIM). The total amount of PAH ranged from 10 to 166 μg/Kg d.w.

Each source gives rise to a characteristic PAH pattern, and it is therefore possible to get access to the processes that generate the compounds. To this aim, the recommended as priority pollutants by the Environmental Protection Agency (EPA), perylene and three additional alkylated compounds were analyzed.

Positive correlations were found between total PAH content of the leaves with CO, benzene and particulate levels measured in air of Palermo.