TETRABUTYLAMMONIUM BROMIDE

Tetrabutylammonium Bromide is a quaternary ammonium salt with a bromide commonly used as a phase transfer catalyst.
Tetrabutylammonium Bromide is used to prepare many other tetrabutylammonium salts by salt metathesis reactions. 
The anhydrous form is a white solid.

CAS:    1643-19-2
MF:    C16H36BrN
MW:    322.37
EINECS:    216-699-2

Synonyms
1-Butanaminium, N,N,N-tributyl-, bromide;1-Butanaminium,N,N,N-tributyl-,bromide;n,n,n-tributyl-1-butanaminiubromide;ALIQUAT(R) 100;IPC-TBA-BR;Tetrabutylazanium bromide;Tetrabutylaminium·bromide;Tetrabutylammonium bromide, 99%, for ion-pair chromatography

In addition to being cheap, Tetrabutylammonium Bromide is also environmentally friendly, has a greater degree of selectivity, is operationally simple, non-corrosive, and can be recycled easily as well.
Tetrabutylammonium Bromide is a tetrabutylammonium salt with bromide as the anionic counterpart. 
Tetrabutylammonium Bromide is an organic bromide salt and a tetrabutylammonium salt.
Tetrabutylammonium Bromide, a quaternary ammonium compound widely used as a phase transfer catalyst. 
Tetrabutylammonium Bromide decreases the retention time and removes peak tailing by acting as an ion pair reagent during the chromatographic analysis of quaternary ammonium compounds. 
In the molten state, Tetrabutylammonium Bromide behaves like an ionic liquid, which is a promising green alternative to organic solvents in polymer synthesis.

Tetrabutylammonium Bromide Chemical Properties
Melting point: 102-106 °C(lit.)
Boiling point: 102 °C
Density: 1.039 g/mL at 25 °C
Bulk density: 700kg/m3
Vapor pressure: 0Pa at 25℃
Refractive index: n20/D 1.422
Fp: 100℃
Storage temp.: Store below +30°C.
Solubility: H2O: 0.1 g/mL, clear, colorless
Form: Crystalline Powder
Pka: 0[at 20 ℃]
Specific Gravity: 1.007
Color: White to slightly cream
Odor: Amine like
PH: 3.5 to 7.0 (50 g/L, 25 ℃)
Water Solubility: 600 g/L (20 ºC)
Sensitive: Hygroscopic
λmax λ: 240 nm Amax: 0.04
λ: 250 nm Amax: 0.03
λ: 260 nm Amax: 0.02
λ: 500 nm Amax: 0.02
BRN: 3570983
Stability: Stable. Incompatible with strong oxidizing agents. Protect from moisture.
InChIKey: JRMUNVKIHCOMHV-UHFFFAOYSA-M
LogP: 0.839 at 25℃
CAS DataBase Reference: 1643-19-2(CAS DataBase Reference)
NIST Chemistry Reference: Tetra-N-butylammonium bromide(1643-19-2)
EPA Substance Registry System: Tetrabutylammonium bromide (1643-19-2)

Tetrabutylammonium Bromide, also known as tetrabutylammonium bromide. 
White crystal, deliquescence. 
118 ℃ melting point. 
Soluble in water, alcohol, ether and acetone, slightly soluble in benzene.

Uses    
(1) Used as a reagent for the analysis of organic synthesis.
(2) Tetrabutylammonium Bromide is also an effective phase transfer catalyst.
Phase transfer catalyst, referred to as PTC, is able to transfer the aqueous phase (or organic phase) to the organic phase (or aqueous phase) catalyst, which can make the reaction between the aqueous phase and the organic phase of the catalyst. 
Tetrabutylammonium Bromide has the function of changing the degree of ion solvation, increasing the activity of ion reaction, speeding up the reaction rate and so on. 
Solve the problem of the past in the two phases of the reaction is difficult to react.
Common quaternary ammonium salt phase transfer catalysts are: benzyl triethyl ammonium chloride, trioctyl methyl ammonium chloride, tetramethyl ammonium bromide, tetrapropylammonium chloride, tetrabutylammonium bromide , tetrabutyl ammonium iodide, benzyl triethyl ammonium bromide, triethyl hexyl bromide, octyl triethylammonium bromide.

Phase transfer catalyst is widely applied in organic synthesis: R2C for preparing compounds (carbene type compound), further preparation of the corresponding nitrile, isonitrile, Halon, dichloromethane cyclopropane derivatives, hydroxy acids and diazomethane. 
For the alkylation reaction, compared with traditional methods, to avoid the harsh conditions of dry operation, and high yield, it can also be used in the redox reaction, ester hydrolysis, substitution reaction, condensation reaction, addition reaction, polymerization reaction, addition reaction of carbon and the elimination of reaction and so on.
(3) For organic synthesis intermediates, phase transfer catalyst
(4) Ion-pairing reagents for the synthesis of bacampicillin, sultamicillin like.
(5) Ion pair chromatography reagents, phase transfer catalyst. 
Bacampicillin, sultamicillin like synthesis.

Tetrabutylammonium Bromide is used in the synthesis of polymer solar cells. 
Also used in the synthesis of single component green-light emitting electrochemical cells.
Tetrabutylammonium Bromide is a quaternary ammonium compound. 
Tetrabutylammonium Bromide is the most widely used phase transfer catalyst. 
Tetrabutylammonium Bromide's interfacial properties have been studied in case of hydroxide initiated reactions. 
Tetrabutylammonium Bromide may be applied in understanding the mechanism of phase transfer reactions. 
Tetrabutylammonium Bromide is reported to decrease retention time and remove peak tailing by acting as an ion pair reagent during the chromatographic analysis of quaternary ammonium compounds. 
In the molten state Tetrabutylammonium Bromide behaves like an ionic liquid which is a promising green alternative to organic solvents in organic synthesis. 
Tetrabutylammonium Bromide's molar heat capacity, entropy and free energy function have been determined.
Recently, molten Tetrabutylammonium Bromide was used as a low toxic and cost-effective IL in a number of constructive synthetic transformations.

Tetrabutylammonium Bromide may be used in the molten state in the following processes:
Synthesis of (2S)-5-(3-phenyl-2-phthalimidylpropanoylamino)isophthalic acid.
Synthesis of alkyl-substituted pyrroles in the absence of catalyst and organic solvent.
Synthesis of dithioacetals from acetals by transthioacetalisation in a solvent free environment.
Synthesis of polyamides (PAs) by the polymerization of terephthalic acid and diisocyanates.
Catalyze the addition of thiols to conjugated alkenes.
Dehydrochlorination of poly(vinyl chloride).

benefits    
Tetrabutylammonium Bromide is an environmentally benign, non-volatile, non-flammable, non-corrosive, low-cost, commercially available ammonium salt with high thermal and chemical stability. 
In Tetrabutylammonium Bromide, tetrabutylammonium salt can dissolve in both aqueous as well as in organic solvents, which helps to transport the water-soluble anionic reactants into the organic phase. 
Moreover, molten Tetrabutylammonium Bromide was also employed as an efficient ionic liquid to carry out organic transformations under solvent-free conditions.

Preparation    
Preparative Methods: several methods are available to recover the quaternary ammonium ion efficiently.
Prepared by reaction of tri-n-butylamine and n-butyl bromide.

Purification Methods    
Crystallise the salt from *benzene (5mL/g) at 80o by adding hot n-hexane (three volumes) and allowing to cool. 
Dry Tetrabutylammonium Bromide over P2O5 or Mg(ClO4)2, under vacuum. 
The salt is very hygroscopic. 
Tetrabutylammonium Bromide can also be crystallised from ethyl acetate or dry acetone by adding diethyl ether and dried in vacuo at 60o for 2 days. 
Tetrabutylammonium Bromide has been crystallised from acetone by addition of diethyl ether. 
Tetrabutylammonium Bromide is so hygroscopic that all manipulations should be carried out in a dry-box. 
Tetrabutylammonium Bromide has been purified by precipitation from a saturated solution in dry CCl4 on addition of cyclohexane or by recrystallisation from ethyl acetate, then heating in vacuum to 75o in the presence of P2O5. 
Tetrabutylammonium Bromide also recrystallises from CH2Cl2/diethyl ether and is dried in a vacuum desiccator over P2O5. 

Preparation and reactions
Tetrabutylammonium Bromide can be prepared by the alkylation of tributylamine with 1-bromobutane.
Tetrabutylammonium Bromide is used to prepare other salts of the tetrabutylammonium cation by salt metathesis reactions.
Tetrabutylammonium Bromide serves as a source of bromide ions for substitution reactions. 
Tetrabutylammonium Bromide is a commonly used phase transfer catalyst.
As Tetrabutylammonium Bromide's melting point is just over 100 °C and decreases in the presence of other reagents, it can be considered an ionic liquid.