Organolead preparation

Halostibines, Dihalostibines, and Related Compounds. Alkyl dichi oro- and alkyldibromostibines are readily prepared by the alkylation of the corresponding antimony trihaUde with an organolead reagent (67,104) ... 

Organolead compounds with a carboxylic acid function bound to the alkyl group can be prepared by addition of Ph3PbOH to ketenes162 ... 

Cycloaddition reactions are used to prepare organolead compounds with functionalized substituents. (Triphenylplumbyl)pyrazole, 95, can be prepared from triorganoplumbylalkynes by 1,3-dipolar cycloadditions with diazomethane196 ... 

Organolead tetrazoles, for instance 96, have been prepared from PhsPbNz, CS2 and RC6H4NCS (R = H, p-Br, OMe, p-Me)372 ... 

Insertion of thienyl or furyl groups into alkyllead compounds can be carried out using organolithium reagents. Thus, organolead(IV) tricarboxylates can be prepared as follows via tin(IV) precursors ... 

Organolead hydrides are prepared from the reduction of organolead halides, usually the methyl and ethyl derivatives, by KBH4 or from the reduction of trialkyllead methoxides R3PbOCH3 (R = Me, Et, w-Pr, w-Bu) with B2H6. 

Functional organolead compounds containing a C—Cl bond can also be prepared by special methods165 ... 

Functional organolead compounds containing C—F bonds can be prepared when R3PbCl reacts with CgFsBr in the presence of P(NEt3)3 to give RsPbCgFs. 

It is interesting to mention that PbCl2 is stable whereas PbCLj is thermodynamically unstable and decomposes at room temperature to yield PbCl2 and elemental CI2. On the other hand, organolead(IV) compounds have been prepared (and have been used extensively as fuel additives, such as PbEtq) whereas species like PbEt2 have yet to be prepared and are likely not possible, as they disproportionate to the more thermodynamically stable PbEt4 and solid Pb. This tendency is also reflected in the reaction enthalpies of the methyl... 

The only non-antiknock use of organolead compounds has been in the preparation of RHgX for application as seed disinfectants and for the control of fungi114. Thiomethyl... 

Furthermore, arylthiophenes have been prepared using the Stille coupling of hypervalent iodonium salts [96] or organolead compounds [97, 98] as electrophiles in place of aryl or vinyl halides and triflates. Hypervalent iodonium salts are sufficiently reactive to undergo coupling at room temperature. 

In the last few years, the interest in organolead(rv) compounds has moved from preparative aspects more to the analytical detection of such compounds or their decomposition products. On the other hand, the synthesis and characterization of low-valent organolead compounds has experienced an impressive increase numerous remarkable results have been achieved, and these constitute the major part of this survey. 

Tris(organoplumbyl)stibines have been prepared by condensing organolead chlorides with stibine (equation 28).97... 

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