Tetrabutylammonium iodide

Chemical properties

Tetrabutylammonium iodide is an organic ammonium compound with the molecular formula C16H36IN. white or tan powder. Soluble in water and ethanol, slightly soluble in chloroform and benzene. Stable under normal temperature and pressure.

The Uses of Tetrabutylammonium iodide

Tetrabutylammonium iodide is used in the preparation of novel quaternary amines to serve as antibacterial agents in the rise of drug-resistant bacteria,it is also used in phosphonium reversible inhibitors of cholinesterases.

The Uses of Tetrabutylammonium iodide

To a solution of the indole (A) (6.0 g, 22.9 mmol) in dry DMF (60 mL) was added K2CO3 (9.52 g, 68.9 mmol) and the mixture was stirred under N2 at RT for 30 min. To this mixture was added the alkyl bromide (B) (5.5 g, 45.9 mmol) and the reaction was stirred at 80 C for 4 h. After completion, the reaction mixture was cooled to RT and diluted with EtOAc (50 mL). The mixture was washed with brine (50 mL), then cold H2O (50 mL). The org layer was dried (Na2SO4) and concentrated in vacuo. The resulting material was purified by silica gel column chromatography to provide the product as an off-white solid. [6.0 g, 87%]

What are the applications of Application

Tetrabutylammonium iodide may be used as a mobile phase additive in ion-pair high-performance liquid chromatography (IP-HPLC) assay of 4-aminopyridine in serum. It may also be used as a mobile phase additive in the analysis of tetracycline by reversed-phase IPC. The addition of tetrabutylammonium iodide regulates the retention of tetracyclines.
Tetrabutylammonium iodide can be used:
As an additive in the synthesis of fused triazole derivatives using palladium catalyst.
To prepare allyl-PEG-allyl, which is a key intermediate polymer used to synthesize fluorinated amphiphilic copolymers.
As a catalyst used in the synthesis of ethers.

Reactions

Tetrabutylammonium iodide (TBAI) has been used as a catalyst in the following reactions:
Synthesis of O-benzyl-N-Boc-L-tyrosine benzyl ester from N-Boc-L-tyrosine.
Conversion of 8-fluoro-1-aminonaphthalene into 1-(8-fluoro-naphthalen-1-yl)piperazine hydrochloride.
Synthesis of 1-(2,4-dichlorophenyl)-5-(4-(4-iodobut-1-ynyl)phenyl)-4-methyl-N-(piperidin-1-yl)-1H-pyrazole-3-carboxamide from 4-(4-(1-(2,4-dichlorophenyl)-4-methyl-3-(piperidin-1-ylcarbamoyl)-1H-pyrazol-5-yl)phenyl)but-3-yn-1-yl methanesulfonate.
Other reactions where TBAI can be used as a catalyst:
TBAI-tert-butyl hydroperoxide system can catalyze the conversion of α-methyl styrene derivatives into allylic sulfones by reacting with sulfonylhydrazides under metal-free conditions.
Palladium(0)-catalyzed cross-coupling between benzylic zinc bromides and aryl or alkenyl triflates.
Three-component coupling of amines, carbon dioxide, and halides to form carbamates in the presence of cesium carbonate.

General Description

Tetrabutylammonium iodide is a quaternary ammonium salt used in phase-transfer reactions. It is also used in regioselective ether cleavage reactions and as a source of iodide for nucleophilic displacement reactions.

Flammability and Explosibility

Not classified

Purification Methods

Crystallise the iodide from toluene/pet ether (see entry for the corresponding bromide), acetone, ethyl acetate, EtOH/diethyl ether, nitromethane, aqueous EtOH or water. Dry it at room temperature under a vacuum. It has also been dissolved in MeOH/acetone (1:3, 10mL/g), filtered and allowed to stand at room temperature to evaporate to ca half its original volume. Distilled water (1mL/g) is then added, and the precipitate is filtered off and dried. It can also be dissolved in acetone, precipitated by adding ether and dried in a vacuum at 90o for 2 days. It has also been recrystallised from CH2Cl2/pet ether or hexane, or anhydrous methanol and stored in a vacuum desiccator over H2SO4. [Chau & Espenson J Am Chem Soc 108 1962 1986, Beilstein 4 IV 558.]