Tri-n-butyltin hydride, 97%

General References:

1. Reducing agent and source of tributyltin radicals. Widely used for selective reduction of alkyl halides to alkanes by a radical chain mechanism. The reaction is tolerant of a wide range of functionality, including OH and NH, in contrast to polar metal hydride reagents. For reviews, see: Synthesis, 499 (1970); 665 (1987). For a brief feature on uses of this reagent in synthesis, see: Synlett, 173 (2007). For use in the synthesis of deoxy sugars via reductive rearrangement of glycosyl bromides, see: Org. Synth. Coll., 8, 583 (1993). Cyclization of the initially-formed alkyl radical to a suitably positioned double bond may occur. Formation of 5-membered rings is strongly favoured, and ring closure onto an existing ring gives the cis-fused product. See, e.g.: J. Am. Chem. Soc., 108, 5893 (1986):
2. Intermolecular coupling with electron-deficient alkenes is also effective: Angew. Chem. Int. Ed., 23, 69 (1984); Org. Synth. Coll., 8, 148 (1993). Review: Synthesis, 417 (1988).
3. Secondary alcohols can be deoxygenated by reduction of their xanthate derivatives: J. Chem. Soc., Perkin 1, 1574 (1975); Org. Synth. Coll., 7, 139 (1990), avoiding the rearrangements encountered with carbocation-based methods.
4. TBTH also cleaves other C-heteroatom bonds, controlled by the stability of the resulting radical: Nitro-groups at tertiary centers are readily cleaved: Synthesis, 693 (1986). Azides are readily reduced to amines: Synlett, 342 (1991). C-S and C-Se bonds are also cleaved. J. Am. Chem. Soc., 104, 2046 (1982); 112, 4008 (1990); J. Org. Chem., 49, 5206 (1984); 54, 1234 (1989).
5. Dialdehydes and keto aldehydes undergo free-radical intramolecular pinacol coupling to give cyclic diols: J. Am. Chem. Soc., 117, 7283 (1995); J. Org. Chem., 63, 6357 (1998).