Trimethyltin chloride


Trimethyltin chloride is an organotin compound with the formula 3SnCl. It is a white solid that is highly toxic and malodorous. It is susceptible to hydrolysis.

Synthesis

Trimethyltin chloride can be prepared by the redistribution reaction of tetramethyltin with tin tetrachloride.
This is the Kocheshkov redistribution reaction. It is performed under an inert atmosphere, such as argon, typically with no solvent.
A second route to Me3SnCl involves treating the corresponding hydroxide or oxide with a halogenating agent such as hydrogen chloride or thionyl chloride :

Uses

Trimethyltin chloride is used as a source of the trimethylstannyl group. For example, it is a precursor to vinyltrimethylstannane and indenyltrimethylstanane:
An example of an organolithium reagent reacting with Me3SnCl to form a tin-carbon bond is:
Organotin compounds derived from Me3SnCl are useful in organic synthesis, especially in radical chain reactions. Me3SnCl is a precursor to compounds used in PVC stabilization.
Reduction of trimethyltin chloride gives tin-tin bonds.
The Lewis acid properties of Me3SnCl have been analyzed by the ECW model yielding EA= 2.87 and CA= 0.71. Trimethyltin chloride forms adducts with many Lewis bases but when it forms an adduct with diethyl ether, steric repulsion between the methyl groups on the Sn and the ethyl groups on oxygen results. However, when the Lewis base is tetrahydrofuran, steric repulsion is reduced. The ECW model can provide a measure of these steric effects.