Tributyltin hydride

Tributyltin hydride is an organotin compound with the formula (C4H9)3SnH. It is a colorless liquid that is soluble in organic solvents. The compound is used as a source of hydrogen atoms in organic synthesis.

Synthesis and characterization
The compound is produced by reduction of tributyltin oxide with polymethylhydrosiloxane:
 * 2 "[MeSi(H)O]n" +  (Bu3Sn)2O   →   "[MeSi(OH)O]n"   +  2 Bu3SnH

The hydride is a distillable liquid that is mildly sensitive to air, decomposing to (Bu3Sn)2O. Its IR spectrum exhibits a strong band at 1814 cm−1 for νSn−H.

Applications
It is a specialized reagent in organic synthesis. Combined with azobisisobutyronitrile (AIBN) or by irradiation with light, tributyltin hydride converts organic halides (and related groups) to the corresponding hydrocarbon. This process occurs via a radical chain mechanism involving the radical Bu3Sn•. The radical abstracts a H• from another equivalent of tributyltin hydride, propagating the chain. Tributyltin hydride's utility as a H• donor can be attributed to its relatively weak bond strength (78 kcal/mol).

It is the reagent of choice for hydrostannylation reactions:
 * RC2R′ +  HSnBu3  →   RC(H)=C(SnBu3)R′