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:12
2 "[MeSi(H)O]n" + (Bu3Sn)2O → "[MeSi(OH)O]n" + 2 Bu3SnHIt can also be synthesized by a reduction of tributyltin chloride with lithium aluminium hydride.
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
See also: Barton–McCombie deoxygenation
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•.34 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).5
It is the reagent of choice for hydrostannylation reactions:6
RC2R′ + HSnBu3 → RC(H)=C(SnBu3)R′See also
Further reading
- Hayashi, K.; Iyoda, J.; Shiihara, I. "Reaction of organotin oxides, alkoxides and acyloxides with organosilicon hydrides. New preparative method of organotin hydrides " J. Organomet. Chem. 1967, 10, 81. doi:10.1016/S0022-328X(00)81719-2
References
Maleczka, Robert E.; Terrell, Lamont R.; Clark, Damon H.; Whitehead, Susan L.; Gallagher, William P.; Terstiege, Ina (1999). "Application of Fluoride-Catalyzed Silane Reductions of Tin Halides to the in Situ Preparation of Vinylstannanes". J. Org. Chem. 64 (16): 5958–5965. doi:10.1021/jo990491+. /wiki/Doi_(identifier) ↩
Tormo, J.; Fu, G. C. (2002). "α-D-Ribo-hexofuranose, 3-deoxy-1,2:5,6-bis-O-(1-methylethylidene)". Org. Synth. 78: 239. doi:10.15227/orgsyn.078.0239. /wiki/Doi_(identifier) ↩
OUP catalogue page, J. Clayden, N. Greeves, S. Warren and P. Wothers, in Organic Chemistry, 2000, OUP, Oxford, ch. 39, pp. 1040-1041. http://www.oup.com/uk/catalogue/?ci=9780198503460 ↩
T. V. (Babu) RajanBabu, Philip C. Bulman Page, Benjamin R. Buckley, "Tri-n-butylstannane" Encyclopedia of Reagents for Organic Synthesis 2004, John Wiley & Sons. doi:10.1002/047084289X.rt181.pub2 /wiki/Doi_(identifier) ↩
Laarhoven, L. J. J.; Mulder, P.; Wayner, D.D. M. "Determination of Bond Dissociation Enthalpies in Solution by Photoacoustic Calorimetry" Acc. Chem. Res. 1999, 32, 342 doi:10.1021/ar9703443 /wiki/Doi_(identifier) ↩
Smith, Nicholas D.; Mancuso, John; Lautens, Mark (2000). "Metal-Catalyzed Hydrostannations". Chemical Reviews. 100 (8): 3257–3282. doi:10.1021/cr9902695. PMID 11749320. /wiki/Doi_(identifier) ↩