Trimethyltin halides

These pioneer works were followed by numerous studies on complexes of trimethyltin halides, the data from which are discussed in the following. 

The more unusual chemical properties of this compound include the formation of a crystalline oxonium adduct with trimethyltin halides,5 as would be expected from its strong donating power,6 namely ... 

Trimethyltin halides are fairly soluble in water, and can often be washed out of a solution of the reaction mixture in an immiscible solvent. If the desired product is polar, it can be separated from tributyltin halides by partition between acetonitrile and hexanes, which are immiscible.52 53... 

The kinetics of halogen exchange in binary mixtures of trimethyltin halides in solution have been investigated by total lineshape analysis. By measurements in solvents of different permittivities it was concluded that ionization does play a part in the kinetics, and that exchange proceeds by a five-co-ordinated intermediate according to Scheme 7. 

Cleavage with formation of the halide is accomplished with a number of reagents other than the halogens. Treatment of hexamethylditin with hydrobromic (206) or hydrochloric (273) acid leads to the corresponding trimethyltin halide. In contrast, hexaethylditin has been found to react with 4 moles of hydrogen chloride to form diethyltin dichloride. 

The quadrupole splitting for R3SnX is very similar to that for R3SnX2, suggesting a similarity of stereochemistry at the tin atom (115). Polymeric structures for the halides involving R3SnX2 units are consistent with x-ray euid infrared data for the trimethyltin halides (31, 99, 109). These results invalidate... 

Rates of halide exchange with trimethyltin halides decrease as the temperature increases. This anomalous behaviour has been ascribed to the following pre-equilibrium association ... 

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