Robert J. Liukkonen

Alkyl Aromatic Synthesis: Nucleophilic Alkyl Lithium Addition

Abstract Alkylated and, in particular, methylated polycyclic aromatic hydrocarbons and heteroaromatic compounds associated with increased coal utilization may be considerably more carcinogenic than the corresponding parent system.1,2 The availability of these alkylated compounds as standards for structural comparison or for biological testing is therefore of some importance. The report describes improvements on methodology for the synthesis of alkyl aromatic compounds by using a nucleophilic addition of an alkyl lithium (often enhanced by UV irradiation)3–11 in combination with the subsequent addition of iodine to conveniently regenerate the aromatic system (Scheme I, Table I).

Histological effects and bioaccumulation potential of coal particulate-bound phenanthrene in the fathead minnow Pimephales promelas

Abstract Fathead minnows Pimephales promelas were exposed to phenanthrene adsorbed to μm coal particles in a 14-day flow-through exposure to determine changes in histology and bioaccumulation. Based on light microscopic examination, coal particulates caused no obvious damage to external surfaces such as gills or skin and particulates were not observed to have accumulated in internal tissues. However, coal particles were readily ingested and this was followed by extensive mucous secretion by the gut mucosa. In addition, electron micrographs of the gut showed mucous globules in coal-exposed epithelium but no erosion of microvilli. Phenanthrene bioacumulation was compared in fish exposed to dissolved aqueous phenanthrene and fish exposed to dissolved aqueous phenanthrene plus coal particulate-bound phenanthrene. Enhanced phenanthrene uptake was not measured in coal-exposed fish and bioconcentration factors were 1000–4000 during the 14-day exposure period. Elimination of coal from the gut and phenanthrene from the tissues was rapid; both were undetectable after a 24-h depuration period.