Uses
Tributyltin hydride (TBTH) is as a reagent for the reductive ionic 1,5-cyclization of 3-azamuconoates (3-azahexa-2,4-dienedioates).
Tributyltin hydride can also mediate cyclisation of unsaturated ethers and amines bearing an aldehyde or α,β-unsaturated ketone group.
Tributyltin hydride is also a reducing agent for the reduction of nitroalkenes.
Chemical Properties
clear colourless liquid
Uses
A widely used radical reagent used in reductive cleavage,1 radical dehalogenation, and intramolecular radical cyclization.2
Uses
Tributyltin hydride is used to effect carbon—carbon bond formation with the displacement of halide from a suitably oriented haloalkyl group.
Uses
Tributyltin hydride the most commonly used tin hydride，it is less toxic than the more volatile trierhyl and trimethyl analogues, and it is therefore the most widely used organostannane.
Tributyltin hydride, the reagent of choice for generating alkyl radical, is also widely used in aryl radical cyclization. Other reagents developed for this purpose include samarium diiodide, palladium reagents organosilanes as well as manganese triacetate and transition metals for carbocyclization.
Application
Has been reviewed. Catalyzes the Si-H reduction of
α,β-unsaturated ketones. Useful in the reductive
amination of ketones and aldehydes to form 3° amines.
Hazard
Moderately toxic by inhalation.
Safety Profile
Moderately toxic by
inhalation. When heated to decomposition it
emits acrid smoke and irritating fumes. See
also TIN COMPOUNDS.
Purification Methods
Dissolve it in Et2O, add quinol (500mg for 300mL, to stabilize it), dry over Na2SO4, filter, evaporate and distil it under dry N2. It is a clear liquid if dry and decomposes very slowly. In the presence of H2O, traces of tributyl tin hydroxide are formed in a few days. Store it in sealed glass ampoules in small aliquots. It is estimated by reaction with aqueous NaOH when H2 is liberated. CARE: stored samples may be under pressure due to liberated H2. [Van Der Kerk et al. J Appl Chem 7 366 1937, Ono et al. Tetrahedron 41 4013 1985, Neuman Synthesis 665 1987, Curran Synthesis 417 1988, Beilstein 4 IV 4312.]
