Preparation of organolead compounds

Diethyl tin dicaprylate is a high-boiling yellow liquid (d420 = 1.14- 1.15, the allowable chlorine content does not exceed 0.2%). 

Dethyltin dicaprylate is used as a stabiliser in polymers and as a catalyst in the process of their production. Besides, the tetraethoxysilane solution of diethyl tin dicaprylate is used as a vulcaniser for elastomers and for the production of silicone compounds and sealants. 

Similarly to diethyl tin dicaprylate, one can also obtain dicaprylate, di-caprynate and distearate of di-n-butyltin and its other organic salts. 

The physicochemical properties of some organic salts of dialkyl tin are given in Table 32. 

Organolead compounds have been recently widely used. They are used in agriculture (as pesticides), in medicine, as well as in various chemical processes as catalysts for the polymerisation of vinyl monomers, chlorination of hydrocarbons, etc. Lead tetraalkyl derivatives are used as additives for engine fuels due to their antiknock properties. 

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The method most used for preparation of organolead compounds in the laboratory is treatment of lead(n) chloride with alkyl-, aryl-, or vinyl-Grignard or -lithium reagents, the main products being as shown in the following summary for magnesium 163,395 463 464... 

SHApmo and Frey (1968) gave an admirable and thorough survey of the preparation of organolead compounds as well as of their chemical and physical properties. 

An excellent survey of the chemical and physical properties and the preparation of organolead compounds has been prepared by Shapiro and Frey [62]. 

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... 

A. L. Prokhorova, in Preparation and Uses of Organolead Compounds, NIITEKhIM, Moscow, 1972, pp. 3-23 (Russian). 

In order to shorten the sample preparation steps, the use of a flow injection (FI) system for the continuous preconcentration of organolead compounds has been studied. It is based on a Cgo fullerene sorbent column and derivatization of the eluent analytes using a Grignard reagent prior to measurement by GC-MS. 

Organomercury compounds were produced by the reaction shown in eq. (4.39) and they were used for agrochemicals such as disinfectants of seeds. But, their poisonous character was pointed out earlier than that of organolead compounds. In Japan, the use of agricultural mercurials was prohibited in 1968. After that, agricultural organomercury compounds have not been prepared [3]. 

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. 

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

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