Trialkyltin hydride-alkyl halide

Trialkyltin hydrides are effective hydrogen atom transfer agents, and trialkyltin radicals wiU abstract chlorine, bromine, or iodine atoms from alkyl halides. Together with a radical initiator, such as AIBN and trialkyltin hydrides, alkyl halides can give reduction or other radical-derived products (Scheme 4.27). 

In 1962, Kuivila showed that the reaction of trialkyltin hydrides with alkyl halides (hydrostannolysis) (equation 1-6) was a radical chain reaction involving short-lived trialkyltin radicals, R3Sn, 12 and in 1964, Neumann showed that the reaction with non-polar alkenes and alkynes (hydrostannation) (equation 1-7) followed a similar mechanism,13, 14 and these reactions now provide the basis of a number of important organic synthetic methods. 

Scheme 7.5. A series of reactions utilized to convert an alkyl halide (1-chlorobutane) to the corresponding alkyltin hydride. The alkyl halide, after reaction with magnesium to produce a Grignard reagent can be hydrolyzed to produce the alkane. The trialkyltin hyride can be used to convert other alkyl halides to their respective alkanes.

Reactions.—Replacement of halogen atoms in alkyl halides with hydrogen can often be achieved by trialkyltin hydride reduction. Two new work-up procedures" "" are said to simplify removal of the organotin halide by-product residues, either by their partition between hexane and acetonitrile " or by their conversion into insoluble polymeric organotin fluorides." ... 

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