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Lowig lead compounds

The development of the chemistry of organic lead compounds can be divided into three stages. Following the preparation of the first alkyllead compound, hexaethyldiplumbane, in 1853 by Lowig 171), attention was focused on the concept of valence and also the development of the structural theory of organic chemistry, mainly in view of early theories of radicals. Then in 1929 Paneth and collaborators 214, 215), in their classical experiment with tetramethyllead and tetraethyllead, were able to prove beyond doubt the existence of short-lived free radicals, long before anything was known of electron spin resonance spectroscopy. [Pg.242]

The forefather of the chemistry of organic compounds of tin and lead was the Swiss chemist Carl Lowig. In the middle of the nineteenth century in the Zurich University laboratory (which was not set up to handle toxic compounds), he developed for the first time several methods for the synthesis of common organic derivatives of these two elements and described their properties41-44. [Pg.4]

Organolead compounds are those in which a lead atom is bound directly to one or more carbon atoms. It is generally accepted that L5wig 210,211) first synthesized an organolead compound in 1853 by reacting a sodium-lead alloy with ethyl iodide. Lowig s product was either or both tetraethyl-... [Pg.28]

As was mentioned in Section 1, the first synthesis of an organolead compound was reported by Lowig 210>211), who synthesized tetraethyllead by the reaction of a sodium-lead alloy with ethyl iodide. Some 35 years later, Polis 247,248) prepared the first aryl lead derivative by the reaction of bromobenzene with a sodium-lead alloy. Since 1923, the sodium-lead alloy-ethyl chloride reaction has been used for the commercial production of tetraethyllead. A similar reaction has also been used for the commercial production of tetramethyllead since 1960. The sodium-lead alloy-alkyl chloride reaction is discussed in Section 6. [Pg.35]

The use of tetraethyl lead (PbEt4), which was first prepared by Lowig as early as 1853, as a fuel additive has raised major environmental concerns to the effect that it is banned in most countries today.Diethyltin iodide was widely distributed in 1954 in France as a cure for staphylococcal infections. The sample, which was contaminated with the much more toxic triethyltin iodide, caused over 100 deaths. Tributyl- or even trioctyltin compounds, which are far more lipophilic, have been used as preservants in plastics, clothes, and as antifouling paintings on ships. They are, however, seen with increasing skepticism and have been mostly replaced by hopefully less toxic compounds. Nonetheless, these examples underscore the necessity for constant and critical evaluation of all the chemicals in common usage. [Pg.897]

Organolead compounds are prepared industrially by an electrolysis process. As the alloy process is the first synthetic reaction of organolead compounds, found by Lowig [1], Shapiro named it the Lowig process at the Symposium of Metal-Organic Compounds in 1957 [8]. It is the reaction of a sodium-lead alloy with organic halides. [Pg.216]


See other pages where Lowig lead compounds is mentioned: [Pg.34]    [Pg.89]    [Pg.34]    [Pg.89]    [Pg.64]    [Pg.794]    [Pg.67]    [Pg.67]    [Pg.29]    [Pg.73]    [Pg.67]    [Pg.67]    [Pg.79]    [Pg.13]    [Pg.215]    [Pg.19]   
See also in sourсe #XX -- [ Pg.4 , Pg.34 , Pg.35 , Pg.49 , Pg.58 , Pg.67 , Pg.68 , Pg.72 , Pg.78 , Pg.79 , Pg.81 , Pg.83 , Pg.89 ]

See also in sourсe #XX -- [ Pg.4 , Pg.34 , Pg.35 , Pg.49 , Pg.58 , Pg.67 , Pg.68 , Pg.72 , Pg.78 , Pg.79 , Pg.81 , Pg.83 , Pg.89 ]




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Lead compounds

Lowig

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