Tetramethylammonium fluoride

Description

Tetramethylammonium fluoride is the quaternary ammonium salt with the formula (CH3)4NF. This hygroscopic white solid is a source of "naked fluoride", that is fluoride ions not connected to a metal atom in a complex. Most other soluble salts of fluoride are in fact bifluorides, HF2–. Historically, there has been two main approaches to prepare TMAF:
(i) Via neutralization of tetramethylammonium hydroxide (TMAOH) with HF.
(ii) through the metathesis reaction of different ammonium salts with inorganic sources of fluoride such as KF or CsF.
Due to the high basicity of the fluoride anion, the salt reacts slowly with acetonitrile, inducing its dimerization to CH3C(NH2)=CHCN, which co-crystallizes.

The Uses of Tetramethylammonium fluoride

Tetramethylammonium fluoride may be used in combination with sulfuryl fluoride for the conversion of aryl phenols to aryl fluorides. It can react with aminosilanes to generate onium amide bases in situ, which can deprotonate heteroarenes.

The Uses of Tetramethylammonium fluoride

Reactant for:

• Halide-induced ring opening of 2-substituted aziridinium salts
• Synthesis of fluoro aromatics via fluorodenitration reactions
• Synthesis of sevoflurane in ionic liquids by halogen-exchange fluorination
• Synthesis of fluorinated Poly(oxomolybdates)

What are the applications of Application

Tetramethylammonium fluoride is useful for halogen exchange