Editing Lead (section)

=== Organolead ===
{{Main|Organolead compound}}

[[File:Tetraethyllead-3D-balls.png|right|thumb|upright|Structure of a [[tetraethyllead]] molecule:<br />
{{Color box|#505050}} [[Carbon]]<br />
{{Color box|#eeeeee}} [[Hydrogen]]<br />
{{Color box|#577179}} Lead|alt=A gray-green sphere linked to four black spheres, each, in turn, linked also to three white ones]]

Lead can form [[catenation|multiply-bonded chains]], a property it shares with its lighter [[Homologous series|homologs]] in the carbon group. Its capacity to do so is much less because the Pb–Pb [[bond energy]] is over three and a half times lower than that of the [[C–C bond]].{{sfn|Greenwood|Earnshaw|1998|p=374}} With itself, lead can build metal–metal bonds of an order up to three.{{sfn|Stabenow|Saak|Weidenbruch|2003}} With carbon, lead forms organolead compounds similar to, but generally less stable<!--as can be seen below--> than, typical organic compounds{{sfn|Polyanskiy|1986|p=43}} (due to the Pb–C bond being rather weak).{{sfn|King|1995|pp=43–63}} This makes the [[organometallic chemistry]] of lead far less wide-ranging than that of tin.{{sfn|Greenwood|Earnshaw|1998|p=404}} Lead predominantly forms organolead(IV) compounds, even when starting with inorganic lead(II) reactants; very few organolead(II) compounds are known. The most well-characterized exceptions are Pb[CH(SiMe<sub>3</sub>)<sub>2</sub>]<sub>2</sub> and [[plumbocene]].{{sfn|Greenwood|Earnshaw|1998|p=404}}

The lead analog of the simplest [[organic compound]], [[methane]], is [[plumbane]]. Plumbane may be obtained in a reaction between metallic lead and atomic hydrogen.{{sfn|Wiberg|Wiberg|Holleman|2001|p=918}} Two simple derivatives, [[tetramethyllead]] and [[tetraethyllead]], are the best-known [[Organolead chemistry|organolead]] compounds. These compounds are relatively stable: tetraethyllead only starts to decompose if heated{{sfn|Toxicological Profile for Lead|2007|p=287}} or if exposed to sunlight or ultraviolet light.{{sfn|Polyanskiy|1986|p=44}}{{efn|[[Tetraphenyllead]] is even more thermally stable, decomposing at 270&nbsp;°C.{{sfn|Greenwood|Earnshaw|1998|p=404}}}} With sodium metal, lead readily forms an equimolar alloy that reacts with [[Haloalkane|alkyl halides]] to form [[Organometallic chemistry|organometallic]] compounds such as tetraethyllead.{{sfn|Windholz|1976}} The oxidizing nature of many organolead compounds is usefully exploited: [[Lead(IV) acetate|lead tetraacetate]] is an important laboratory reagent for oxidation in organic synthesis.{{sfn|Zýka|1966|p=569}} Tetraethyllead, once added to automotive gasoline, was produced in larger quantities than any other organometallic compound,{{sfn|Greenwood|Earnshaw|1998|p=404}} and is still widely used in [[avgas|fuel for small aircraft]].<ref>{{cite web|url=https://www.flyingmag.com/when-will-we-see-unleaded-av-gas/|title=When will we see unleaded AvGas?|date=5 August 2019 |access-date=2024-05-26}}</ref>
Other organolead compounds are less chemically stable.{{sfn|Polyanskiy|1986|p=43}} For many organic compounds, a lead analog does not exist.{{sfn|Wiberg|Wiberg|Holleman|2001|p=918}}