chemistry Chemistry is the science, scientific study of the properties and behavior of matter. It is a natural science that covers the Chemical element, elements that make up matter to the chemical compound, compounds made of atoms, molecules and ions ...

, a fatty amine is loosely defined as any

amine In chemistry, amines (, ) are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia (), wherein one or more hydrogen atoms have been replaced by a substituen ...

possessing a mostly linear

hydrocarbon In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic, and their odors are usually weak or ...

chain of eight or more carbon atoms. They are typically prepared from the more abundant

fatty acid In chemistry, particularly in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated or unsaturated. Most naturally occurring fatty acids have an unbranched chain of an even number of carbon atoms, ...

s, with vegetable or seed-oils being the ultimate starting material. As such they are often mixtures of chain lengths, ranging up to about C22. They can be classified as

oleochemical Oleochemistry is the study of vegetable oils and animal oils and fats, and oleochemicals derived from these fats and oils. The resulting product can be called oleochemicals (from Latin: oleum "olive oil"). The major product of this industry is soa ...

s. Commercially important members include coco amine,

oleylamine Oleylamine is an organic compound with a molecular formula C18H35NH2. It is an unsaturated fatty amine related to the fatty acid oleic acid. The pure compound is a clear and colorless liquid. Commercially available oleylamine reagents vary in colo ...

, tallow amine, and soya amine. These compounds and their derivatives are used as

fabric softener A fabric softener (American English) or fabric conditioner (British English) is a conditioner that is applied to laundry during the rinse cycle in a washing machine to reduce harshness in clothes that are dried in air after machine washing. In con ...

froth flotation Froth flotation is a process for selectively separating hydrophobic materials from hydrophilic. This is used in mineral processing, paper recycling and waste-water treatment industries. Historically this was first used in the mining industry, wher ...

agents (purification of ores),

corrosion inhibitor In chemistry, a corrosion inhibitor or anti-corrosive is a chemical compound that, when added to a liquid or gas, decreases the corrosion rate of a material, typically a metal or an alloy, that comes into contact with the fluid. The effectiveness ...

s, lubricants and

friction modifier Friction modifiers are added to lubricants in order to reduce friction and wear in machine components. They are particularly important in the boundary lubrication regime, where they can prevent solid surfaces from coming into direct contact, substa ...

s. They are also the basis for a variety of cosmetic formulations.

Production and reactions

Fatty amines are commonly prepared from

fatty acids In chemistry, particularly in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated and unsaturated compounds#Organic chemistry, saturated or unsaturated. Most naturally occurring fatty acids have an B ...

; which are themselves obtained from natural sources, typically seed-oils. The overall reaction is sometimes referred to as the Nitrile Process and begins with a reaction between the fatty acid and

ammonia Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogenous wa ...

at high temperature (>250 °C) and in the presence of a metal oxide catalyst (e.g., alumina or zinc oxide) to give the fatty nitrile. : RCOOH + NH₃ → RC≡N + 2 H₂O The fatty amine is obtained from this by

hydrogenation Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organ ...

with any of a number of reagents, including Raney nickel or cobalt, and

copper chromite Copper chromite is an inorganic compound with the formula Cu2Cr2O5. It is a black solid that is used to catalyze reactions in organic synthesis. History The material was first described in 1908. The catalyst was developed in North America by Home ...

catalysts. When conducted in the presence of excess ammonia the hydrogenation affords the primary amines. : RCN + 2 H₂ → RCH₂NH₂ In the absence of ammonia, secondary and tertiary amines are produced. :2 RCN + 4 H₂ → (RCH₂)₂NH + NH₃ :3 RCN + 6 H₂ → (RCH₂)₃N + 2 NH₃

Fatty secondary and tertiary amines

Alternatively, secondary and tertiary fatty amines can be generated by the reaction of fatty alcohols and fatty alkyl bromides with (di)alkylamines. For example 1-bromododecane reacts with

dimethyl amine Dimethylamine is an organic compound with the formula (CH3)2NH. This secondary amine is a colorless, flammable gas with an ammonia-like odor. Dimethylamine is commonly encountered commercially as a solution in water at concentrations up to aroun ...

: :RBr + HNMe₂ → RNMe₂ + HBr By reaction with tertiary amines, long-chain alkyl bromides give

quaternary ammonium salts In chemistry, quaternary ammonium cations, also known as quats, are positively charged polyatomic ions of the structure , R being an alkyl group or an aryl group. Unlike the ammonium ion () and the primary, secondary, or tertiary ammonium cations ...

, which are used as

phase transfer catalyst In chemistry, a phase-transfer catalyst or PTC is a catalyst that facilitates the transition of a reactant from one phase into another phase where reaction occurs. Phase-transfer catalysis is a special form of heterogeneous catalysis. Ionic rea ...

s. Secondary and tertiary amines may also be produced by the

Leuckart reaction The Leuckart reaction is the chemical reaction that converts aldehydes or ketones to amines by reductive amination in the presence of heat. The reaction, named after Rudolf Leuckart, uses either ammonium formate or formamide as the nitrogen do ...

. This reaction effects N-methylation using

formaldehyde Formaldehyde ( , ) (systematic name methanal) is a naturally occurring organic compound with the formula and structure . The pure compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde (refer to section F ...

with formic acid as the reductant. These tertiary amines are precursors to

quaternary ammonium salt In chemistry, quaternary ammonium cations, also known as quats, are positively charged polyatomic ions of the structure , R being an alkyl group or an aryl group. Unlike the ammonium ion () and the primary, secondary, or tertiary ammonium cation ...

s used for a variety of applications.

Applications and derivatives

The main application of fatty amines is for the production of the corresponding

s, which are used as

s and hair conditioners (e.g.

Behentrimonium chloride Behentrimonium chloride, also known as docosyltrimethylammonium chloride or BTAC-228, is a yellow waxlike organic compound with chemical formula , used as an antistatic agent and, sometimes, a disinfectant. It is commonly found in cosmetics su ...

). Fatty amines are also used in

, for the beneficiation of various ores. The amines bind to the surfaces of certain minerals allowing them to be readily separated from those lacking the bound amine. They are also additives in the production of

asphalt Asphalt, also known as bitumen (, ), is a sticky, black, highly viscous liquid or semi-solid form of petroleum. It may be found in natural deposits or may be a refined product, and is classed as a pitch. Before the 20th century, the term ...

References

{{Reflist Amines