Harger reaction

Denmark, S. E., Dorow, R. L. The stereochemical course of migration from phosphorus to nitrogen in the photo-Curtius rearrangement of phosphinic azides (Harger reaction). J. Org. Chern. 1989, 54, 5-6. 

Based on results from concurrent environmental chamber studies of the photooxidations of naphthalene, fluorene, and phenanthrene by Arey and coworkers (1992), Harger and co-workers attributed a significant fraction of the vapor-phase direct activity of fraction 4 (Fig. 10.25) to 2-nitronaphthalene (2-NN) present in these 12-h daytime samples as a result of an OH-initiated homogeneous gas-phase reaction of naphthalene in ambient air. Although 1-nitronaphthalene (1-NN) is also present at significant concentrations in both ambient and laboratory systems, it is a much weaker, direct mutagen (see Table 10.20 Arey et al., 1992). 

For example, Fig. 10.37 shows a mutagram of an extract of ambient gas-phase POM collected on polyurethane foam plugs in Claremont, California, along with mutagrams of the extracts of PUF samples collected from environmental chamber studies of the OH radical initiated reactions of fluorene and naphthalene, respectively (Arey et al., 1992 Harger et al., 1992 Atkinson and Arey, 1994). Clearly, the mutagrams from the OH-initiated reactions are very similar to that of ambient air. 

FIGURE 10.37 Mutagrams of extracts of an ambient sample of gas-phase direct mutagens collected on a PUF plug in Claremont, California, and, for comparison, extracts of the vapor-phase products from the OH radical initiated gas-phase reactions of naphthalene and fluorene in an environmental chamber. For naphthalene, the mutagenicity of fraction 4 is primarily due to the presence of 1- and 2-nitronaphthalene. Fraction 4 from the fluorene reaction contains four nitrofluorene isomers, with 3-nitrofluorene being dominant (adapted from Arey et al., 1992 Harger et al., 1992). 

Helmig, D., J. Arey, R. Atkinson, W. P. Harger, and P. A. McElroy, Products of the OH Radical-Initiated Gas-Phase Reaction of Fluorene in the Presence of NOx, Atmos. Environ., 26A, 1735-1745 (1992c). 

Kwok, E. S. C., W. P. Harger, J. Arey, and R. Atkinson, Reactions of Gas-Phase Phenanthrene under Simulated Atmospheric Conditions, Environ. Sci. Technol., 28, 521-527 (1994a). 

Pitts, J. N., Jr., J. A. Sweetman, B. Zielinska, A. M. Winer, R. Atkinson, and W. P. Harger, Formation of Nitroarenes from the Reaction of Polycyclic Aromatic Hydrocarbons with Dinitrogen Pentoxide, Environ. Sci. Technol., 19, III5-II2I (I985e). 

Although strictly outside the remit of this chapter, it is appropriate to note continued activity in the chemistry of c X -p -bonded phosphorus compounds that do not possess a lone pair of electrons at phosphorus. A monomeric metaphosphonate species (262, X=0) has been stabilised by coordination via the P=0 bond), and Harger s group has provided evidence of the intermediacy of metathiophosphonates (262, X=S) in the reactions of phosphonami-dothioic acids with alcohols.The cation (263) has been stabilised by coordination at phosphorus with 4-dimethylaminopyridine and the reactivity of bis(methylene)phosphoranes (264) and related phosphoranylidene car-benoids has been investigated. ... 

Harger and his co-workers have continued to investigate substitution and other reactions of P(V) acid derivatives which show unexpected comparative rates or... 

Harger, M.J.P., and Williams, A., Reactions of iV-phenyl a-halogenophosphonamidates with alkoxide. Migration of the anilino group from phosphorus to the a carbon atom, J. Chem. Soc., Perkin Trans. 1, 1681, 1986. 

Pitts, J. N. Jr., Sweetman, J. A., Zielinska, B., Winer, A. M., Atkinson, R., and Harger, W. P. (1985b) Formation of nitroarenes from the reaction of polycyclic aromatic hydrocarbons with dinitrogen pentoxide. Environ. Sci. Technoi, 19, 1115-1121. 

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