Tetra-n-butylammonium fluoride, 1M soln. in THF is used as a reactant for the preparation of triple monoamine reuptake inhibitors as a new generation of antidepressants, oligoribonucleotides with phosphonate-modified linkages, conjugated dienoic acid esters using Suzuki coupling reactions and polyacetylenic glucosides. It plays an important role in aryl alkyl alcohols through Nozaki-Hiyama allylation catalyzed by chiral bipyridyldiol ligands and chromium trichloride. It is also used as a catalyst for the silylation reactions. In addition, it is used as a source of fluoride ion in organic solvents as well as for the deprotection of silyl ether groups.
Mild catalyst for the silylation of OH by silazanes: Tetrahedron Lett., 35, 8409 (1994), or by hydrosilanes and disilanes: Tetrahedron Lett., 35, 8413 (1994). See Appendix 4.
Specific reagent for the cleavage of silyl ethers, including TBDMS: J. Am. Chem. Soc., 94, 6190 (1972), (see tert-Butyldimethylchlorosilane, A13064), as well as the more stable TBDPS: Org. Synth. Coll., 9, 4 (1998), and TIPS: J. Org. Chem., 45, 4797 (1980); (see also tert-Butyldiphenylchlorosilane, A12721 and Chlorotriisopropylsilane, A17376).
Ester enolates can be displaced from silicon, and trapped by reaction with carbonyl compounds without ɑ-hydrogens: Tetrahedron Lett., 1699 (1976). Under similar conditions, ketones with ɑ-hydrogens are converted under kinetic control to their silyl enol ethers with high (Z)-stereoselectivity (see Ethyl (trimethylsilyl)acetate, A17707): J. Am. Chem. Soc., 98, 2346 (1976); Org. Synth. Coll., 7, 512 (1990):
For the cleavage of disilanes to give "metal-free" silyl anions, see Hexamethyldisilane, A13155.
Promotes the directed aldol condensation of silyl enol ethers with aldehydes at low temperatures under very mild conditions: J. Org. Chem., 48, 932 (1983); alkali metal fluorides give poor results.
Reagent for deprotection of N-Boc groups under mild conditions: Tetrahedron Lett., 43, 589 (2002).
Many other examples exist where the reagent acts as a base in organic synthesis:
Acylation of hindered OH groups: Tetrahedron Lett., 1691 (1977). Nitro-aldol formation from aldehydes and nitro compounds (Henry reaction) facilitated by high pressure: Angew. Chem. Int. Ed., 23, 617 (1984). Dieckmann-type cyclization of a diester: Org. Synth. Coll., 8, 71 (1993). Catalyzes the regioselective N-alkylation of silylated purines with chloromethyl ethers: Helv. Chim. Acta, 72, 1495 (1989).
For nucleophilic displacement of halide or tosylate by TBAF in the preparation of alkyl and acyl fluorides, see: J. Org. Chem., 49, 3216 (1984); Org. Synth. Coll., 8, 258 (1993).
Fluoride ion as a base in organic synthesis: Chem. Rev., 80, 429 (1980). Synthetic aspects of the use of organosilicon compounds under nucleophilic catalysis conditions: Tetrahedron, 44, 2675 (1988). For a brief feature on uses of TBAF, see: Synlett, 2125 (2002).
Zhang, F.; Wu, X.; Wang, L.; Liu, H.; Zhao, Y. General and efficient one-pot synthesis of novel sugar/heterocyclic (aryl) 1, 2-diketones from sugar terminal alkynes by Sonogashira/tetra-n-butylammonium permanganate oxidation. Carbohydr. Res. 2015, 417 41-51.
Parr, B. T.; Economou, C.; Herzon, S. B. A concise synthesis of (+)-batzelladine B from simple pyrrole-based starting materials. Nature 2015, 525 (7570), 507-510.
Hazard Statements: H225-H302-H333-H314-H318-H351-H335
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