Organoleads lead oxides

Organolead carboxylates containing a lead oxide (Pb-O-Pb) and hydroxide (Pb-O-H) entity are compiled in Table 295 Organolead carboxylates supposedly having a carboxylate and alkoxide group linked to one lead atom are reported in Subchapter... 

The common compounds of lead derive from the +2 oxidation state. As a number of the periodic group IV-A, lead also forms tetravalent compounds, which are covalent. The most important are the tetraalkylleads, which are used as gasoline additives. The Pb - C bond is very non-polar, and the organolead species tend to be kinetically inert, like organomercurials. 

The reaction of lead tetraacetate with alkenes and arenes involve first an electrophilic addition step. The intermediate organolead derivative then can follow various pathways to yield oxidation products. 

Lead enters surface water from atmospheric fallout, run-off, or wastewater. Little lead is transferred from natural minerals or leached from soil. Pb ", the stable ionic species of lead, forms complexes of low solubility with major anions in the natural environment such as the hydroxide, carbonate, sulfide, and sulfate ions, which limit solubility. Organolead complexes are formed with humic materials, which maintain lead in a bound form even at low pH. Lead is effectively removed from the water column to the sediment by adsorption to organic matter and clay minerals, precipitation as insoluble salt (the carbonate, sulfate, or sulfide) and reaction with hydrous iron, aluminum, and manganese oxides. Lead does not appear to bioconcentrate significantly in fish but does in some shellfish such as mussels. When released to the atmosphere, lead will generally occur as particulate matter and will be subject to gravitational settling. Transformation to oxides and carbonates may also occur. 

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