Borane Tert-Butylamine

Aug 24, 2022 | SCIENCE, Chemistry

All About Borane Tert-Butylamine

Borane tert-butylamine is an amine borane compound produced from tert-butylamine. It’s a colorless solid with various organic synthesis and photo processing uses.

Butylamine

Butylamine

Amine Borane

Amine boranes are a class of amine-substituted boranes. These are Lewis acids and can be used for direct amidation, activating aliphatic and aromatic carboxylic acids, and then delivering amines to yield the corresponding amides in up to 99%. The delivery of low-boiling or gaseous amines as borane complexes have a significant advantage over traditional amination methods.

Butylamine

Butylamines are butane-derived organic amines primarily used as the main stages for manufacturing industrial chemicals. In some cases, they are also used as food additives. Butylamines are highly combustible, colorless liquids with somewhat fishy or ammonia-like odors. The amines exist in four isomeric forms: n-butylamine, sec-butylamine, tert-butylamine, and isobutylamine. 

N-Butylamine is an organic amine with the formula CH3(CH2)3NH2. This compound is used for manufacturing pesticides, pharmaceuticals, and emulsifiers. It is also a precursor for forming N, N′-dibutyl thiourea, a rubber vulcanization accelerator, and n-butylbenzenesulfonamide, a nylon plasticizer. 

Sec-Butylamine has the chemical formula CH3CH2CH(NH2)CH3 and is used for manufacturing pesticides. 

Isobutylamine (CH3)2CHCH2NH2 is used for pesticides, flavors, rubber chemicals, corrosion inhibitors, mineral flotation agents, polymerization catalysts, gasoline earthquakes, and stabilizers.

tert-butylamine is a white liquid with the formula (CH3)3CNH2 and has a characteristic amine odor. Tert-B (butylamine) is a valuable intermediate for preparing various important chemicals. Rubber accelerators, for example, are made with it to help vulcanize rubber more efficiently. Additionally, many pesticides are derived from tert-butylamine, including terbacil, terbutryn, and terbumeton. Finally, this is also used in pharmacology, which functions as a counterion to drug substances such as perindopril erbumine. In short, it plays a vital role in many industries and applications, making it an essential chemical for modern life.

Preparation of Tert Butylamine

Commercially, tert-b is synthesized by the amination of isobutylene with zeolite catalysts:

NH3 + CH2=C(CH3)2 → H2NC(CH3)3

The isobutene-hydrogen cyanide Ritter reaction is ineffective because it generates too much waste.

(CH3)2C=CH2 + HCN + H2O → (CH3)3CNHCHO

(CH3)3CNHCHO + H2O → (CH3)3CNH2 + HCO2H

It can be prepared in the lab by hydrogenolysis 2,2-dimethylethylenimine or using tert-butylphthalimide.

Properties

Tert ButylamineSpecifications
Chemical formulaC4H11N
Molecular Weight73.139 g/mol
Melting Point−67.50 °C
Boiling point43 to 47 °C
Density0.696 g/mL
AppearanceColorless liquid
OdorFishy, Ammoniacal
Solubility In WaterMiscible
Vapor Pressure39.29 kPa (at 20 °C)
Refractive index (nD)1.377
 

Tert butylamine can be harmful if inhaled or absorbed through the skin. This chemical is corrosive, and its contact can irritate and burn the skin and eyes. Breathing in it can also irritate the nose and throat and cause coughing and difficulty breathing. In severe cases, exposure to this can lead to pulmonary edema, a medical emergency characterized by fluid buildup in the lungs. Tert-B may also affect the liver. This chemical is flammable and presents a fire hazard.

Tert butylamine along with borane prepares an amine-borane complex, borane Tert-B. 

Properties of Borane Tert Butylamine

Borane Tert butylamineSpecifications
Chemical formulaC4H14BN
Molecular Weight86.97 g/mol
Melting Point96°C
AppearanceWhite solid
Solubility In Water27 g/L at 20°C
Storage & SensitivityAmbient temperatures

Borane Tert-B Dehydrogenation Assisted by Ionic Liquid

Ionic liquids (ILs) are a class of salt-like materials liquid at room temperature. They are effective solvents for dehydrogenating tert-b borane (TBAB) at high temperatures.

TBAB solubility in ionic liquids was determined by the conductor-like screening model segment activity coefficient (COSMO-SAC) model for screening for potential IL solvents. For TBAB in 1-butyl-3-methylimidazolium acetate (BMIM][OAc]), the COSMO-SAC model estimates logarithmic infinite dilution activity coefficients of -6.66 while in trihexyl(tetradecyl)phosphonium bis(2,4,4-trimethylpentyl)phosphinate (TDTHP][Phosph], the coefficient is -7.31.

At 105 °C, TBAB/[BMIM][OAc] produced 1.95 equiv of hydrogen, whereas TBAB/[TDTHP][Phosph] formed 1.63 equiv of hydrogen after 6 hours of dehydrogenation. The structural integrity of ILs during dehydrogenation was revealed by proton nuclear magnetic resonance (1H NMR) characterization of TBAB/IL systems. 

Further investigation using the boron NMR (11B NMR) technique revealed the starting compound’s time-resolved formation and stability, intermediate boron moieties, and product distribution. The 11B NMR characterization also revealed that the TBAB/[TDTHP][Phosph] combination dehydrogenates through the bimolecular addition of TBAB, leading to the formation of borohydride anion (BH4–). 

It was observed to oligomerize after adding TBAB to the oligomer chain. The 11B NMR characterization of the TBAB/[BMIM][OAc] system couldn’t recognize the borohydride anion and yet confirmed a faster creation of the B═N moiety, particularly in comparison to the TBAB/[TDTHP][Phosph] system.

Applications of Borane Tert Butylamine

The complex is a mild reducing agent that has been used in a variety of synthetic reactions. Most notably, it has been used in the stereoselective reduction of a steroidal ketone. This reaction is important for the synthesis of many biologically active compounds. 

In addition, the complex has also been used as a co-reducing agent in the syntheses of copper (I) oxide nanoparticles, 4-acetoxycinnamyl alcohols, and diphosphine-protected gold nanoclusters.

It is employed in the E-4 process in photography processing as a chemical enlighting stage in film processing.

Besides being the most promising reducing agent, it can also react with carboxylic functions.

Borane Tert Butylamine is also used in:

  • Non-destructive studies and conservation treatments of Indian artwork.
  • Dehydrogenation processes by ruthenium bidentate phosphine compounds or ruthenium/iridium bis(N-heterocyclic carbene) compounds.
  • The synthesis of σ-borane compounds.
  • Ethanolysis of amine borane intermediates produces a reducing mechanism for terminal olefin transfer hydrogenation.
  • Oxidation and photochemical hydroboration of single-walled carbon nanotubes.

Hazards

  • If swallowed, it is toxic.
  • When it comes into contact with skin, it becomes unhealthy.
  • It irritates the skin.
  • It causes severe eye irritation.
  • It irritates the lungs.

Precautions

  • Keep in a cool place. 
  • Close the container tightly and store it in a dry and well-ventilated area.
  • Acids and oxidizing agents are incompatible with it.