Synthesis
Organolead compounds can be derived from Grignard reagents and lead chloride. For example methylmagnesium chloride reacts with lead chloride to tetramethyllead, a water-clear liquid with boiling point 110 °C and density 1.995 g/cm³. Reaction of a lead(II) source with sodium cyclopentadienide gives the lead metallocene, plumbocene.
Certain arene compounds react directly with lead tetraacetate to aryl lead compounds in an electrophilic aromatic substitution. For instance anisole with lead tetraacetate forms 'p-methoxyphenyllead triacetate in chloroform and dichloroacetic acid:
Other compounds of lead are organolead halides of the type RnPbX(4-n), organolead sulfinates (RnPb(OSOR)(4−n)) and organolead hydroxides (RnPb(OH)(4−n)). Typical reactions are :
- R4Pb + HCl → R3PbCl + RH
- R4Pb + SO2 → R3PbO(SO)R
- R3PbCl + 1/2Ag2O (aq) → R3PbOH + AgCl
- R2PbCl2 + 2 OH− → R2Pb(OH)2 + 2 Cl−
R2Pb(OH)2 compounds are amphoteric. At pH lower than 8 they form R2Pb2+ ions and with pH higher than 10, R2Pb(OH)3- ions.
Derived from the hydroxides are the plumboxanes:
- 2 R3PbOH + Na → (R3Pb)2O + NaOH + 1/2 H2
which give access to polymeric alkoxides:
- (R3Pb)2O + R'OH → 1/n (R3PbOR')n - n H2O
Read more about this topic: Organolead Compound
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