Abstract. The synthesis is reported of the five mononitrofluoranthenes. 1-Nitrofluoranthene was synthesized in 20% from fluoranthene, 2-nitrofluoranthene in 24% from 1,2,3,10b-tetrahydrofluoranthene, 3-nitrofluoranthene in 13% from fluoranthene and 7-and 8-nitrofluoranthene in 34% from 1,2,3,10b-tetrahydrofluoranthene. The pure nitrofluoranthenes were converted into their nitroso and amino analogues. The nitrosopyrenes were also synthesized. Characterisation of each compound is described.
Nitrated polycyclic aromatic hydrocarbons (nitro-PAH) constitute a class of widespread environmental contaminantsThese nitro-PAH can be formed directly during incomplete combustion processes or indirectly via atmospheric reactions of their parent PAH',,. Nitro-PAH are potent mutagens and carcinogens, which pose significant hazards to human health','.'. The position of the nitro group has a large effect on the biological activity6.','. During their metabolism, nitro-PAH may be converted into nitroso and amino derivatives"."'.' I . These substituents also have a profound effect on the mutagenicity and carcinogenicity'.l2.''. In order to detect and identify nitro-PAH and to obtain a better understanding of their chemical properties and biological activities, it is necessary to have available pure reference rnaterial~'~. In previous papers, our group has described the synthesis of the mononitropyrenes and the mononitrocyclopenta[cd]pyrenes'5~'h~'7. 2-Nitrofluoranthene is one of the most abundant nitro-PAH found in airborne particles'. 3-, 7-And 8-nitrofluoranthene are also found in polluted air". 1-, 3-, 7-And 8-nitrofluoranthene are known to be present in diesel exhaust". This motivated us to prepare each of the five possible nitrofluoranthenes in pure form at the 100-mg scale. Access to the pure nitrofluoranthene isomers allowed us also to prepare the corresponding nitroso and amino derivatives at the 100-mg scale in high purity. In this paper, we describe the preparation of 1-, 2-, 3-, 7-and 8-nitrofluoranthenes, 1-, 2-, 3-, 7-, and 8-nitrosofluoranthenes and 1-, 2-, 3-, 7-and 8-fluoranthenamines. The spectroscopic characterisation of each compound is also described. The biological activity of these compounds will be the subject of a future paper.
Results and discussion
SynthesisA common method for the introduction of a nitro group in a PAH is direct nitration of the parent PAH. Treatment of fluoranthene with ammonium nitrate and trifluoroacetic acid anhydride in acetonitrile*' gave a mixture of four mononitrofluoranthenes with 3-nitrofluoranthene (13) as the main isomer. 3-Nitrofluoranthene could be isolated from this mixture in pure form by chromatography on silica (Scheme 1). In this way, 480 mg of 3-nitrofluoranthene was obtained from fluoranthene in 13 % yield.For the preparation of the other mononitrofluoranthenes, derivatives of fluoranthene with a partially hydrogenated skeleton were required. The synthesis of 1-nitrofluoranthene (11) is depicted in Scheme 2. Birch reduction of fluoranthene gave, via 1 ,lob-dihydrofluora...
