11-Aminoundecanoic acid is an

organic compound Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-co ...

with the formula H₂N(CH₂)₁₀CO₂H. This white solid is classified as an amine and a

fatty acid In chemistry, in particular 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 ...

. 11-Aminoundecanoic acid is a precursor to Nylon-11.

Production

As practiced by

Arkema Arkema S.A. is a Public company, publicly listed, multi-national manufacturer of specialty materials, headquartered in La Défense, near Paris, France. It has three specialty materials segments (or divisions); Adhesive, adhesives, advanced mater ...

, 11-aminoundecanoic acid is prepared industrially from

undecylenic acid Undecylenic acid is an organic compound with the formula CH2=CH(CH2)8CO2H. It is an unsaturated fatty acid. It is a colorless oil. Undecylenic acid is mainly used for the production of Nylon-11 and in the treatment of fungal infections of the s ...

, which is derived from

castor oil Castor oil is a vegetable oil pressed from castor beans, the seeds of the plant ''Ricinus communis''. The seeds are 40 to 60 percent oil. It is a colourless or pale yellow liquid with a distinct taste and odor. Its boiling point is and its den ...

. The synthesis proceeds in four separate reactions:

Transesterification of castor oil to methyl ricinoleate

Crude castor oil consists of about 80% triglycerides, from the

ricinoleic acid Ricinoleic acid, formally called 12-hydroxy-9-''cis''-octadecenoic acid, is a fatty acid. It is an Unsaturated fatty acid, unsaturated omega-9 fatty acid and a hydroxy acid. It is a major component of the seed oil obtained from the seeds of casto ...

, itself representing about 90% of the oil. It is quantitatively transesterified with

methanol Methanol (also called methyl alcohol and wood spirit, amongst other names) is an organic chemical compound and the simplest aliphatic Alcohol (chemistry), alcohol, with the chemical formula (a methyl group linked to a hydroxyl group, often ab ...

methyl ricinoleate Methyl ricinoleate is a clear, viscous fluid that is used as a surfactant, cutting fluid additive, lubricant, and plasticizer. It is a plasticizer for cellulosic resins, polyvinyl acetate, and polystyrene. It is a type of fatty acid methyl ester ...

(the methyl ester of ricinoleic acid) in the presence of the basic sodium methoxide at 80 °C within 1 h reaction time in a stirred reactor. At the end of the reaction, the resulting glycerol separates and the liquid methyl ester is washed with water to remove residual

glycerol Glycerol () is a simple triol compound. It is a colorless, odorless, sweet-tasting, viscous liquid. The glycerol backbone is found in lipids known as glycerides. It is also widely used as a sweetener in the food industry and as a humectant in pha ...

. :

Pyrolysis Pyrolysis is a process involving the Bond cleavage, separation of covalent bonds in organic matter by thermal decomposition within an Chemically inert, inert environment without oxygen. Etymology The word ''pyrolysis'' is coined from the Gree ...
of methylricinoleate to heptanal and methyl undecenoate

Methylricinoleate is evaporated at 250 °C, mixed with hot steam (600 °C) in a 1:1 ratio and decomposed in a cracking furnace at 400 - 575 °C at a retention time of about 10 seconds into its cleavage products

heptanal Heptanal or heptanaldehyde is an alkyl aldehyde. It is a colourless liquid with a strong fruity odor, which is used as precursor to components in perfumes and lubricants. Production The formation of heptanal in the fractional distillation of cas ...

and methyl undecenoate. The cleavage of the aliphatic chain occurs in this variant of the steam cracking selectively between the hydroxymethylene and the allyl-methylene group. Besides heptanal and methyl undecenoate, a mixture of

methyl esters In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom chemical bond, bonded to three hydrogen atoms, having chemical formula (whereas normal methane has the formula ). In chemical formula, formulas, t ...

saturated Saturation, saturated, unsaturation or unsaturated may refer to: Chemistry *Saturated and unsaturated compounds, a classification of compounds related to their ability to resist addition reactions **Degree of unsaturation **Saturated fat or satur ...

and unsaturated C18-carboxylic acids is obtained. This mixture is known under the trade name Esterol and is used as a lubricant additive. :

Hydrolysis of methyl undecenoate to 10-undecenoic acid

The hydrolysis of the methyl ester with

sodium hydroxide Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula . It is a white solid ionic compound consisting of sodium cations and hydroxide anions . Sodium hydroxide is a highly corrosive base (chemistry), ...

proceeds at 25 °C within 30 min with quantitative yield. After acidification with

hydrochloric acid Hydrochloric acid, also known as muriatic acid or spirits of salt, is an aqueous solution of hydrogen chloride (HCl). It is a colorless solution with a distinctive pungency, pungent smell. It is classified as a acid strength, strong acid. It is ...

, solid 10-undecenoic acid (undecylenic acid) is obtained. : Hydrolyse Methylundecenoat

Hydrobromination of 10-undecenoic acid to 11-bromoundecanoic acid

The undecenoic acid is dissolved in toluene and, in the presence of the

radical initiator In chemistry, radical initiators are substances that can produce radical species under mild conditions and promote radical reactions. These substances generally possess weak bonds—bonds that have small bond dissociation energies. Radical in ...

benzoyl peroxide Benzoyl peroxide is a chemical compound (specifically, an organic peroxide) with structural formula , often abbreviated as (BzO)2. In terms of its structure, the molecule can be described as two benzoyl (, Bz) groups connected by a peroxide ...

(BPO), gaseous

hydrogen bromide Hydrogen bromide is the inorganic compound with the formula . It is a hydrogen halide consisting of hydrogen and bromine. A colorless gas, it dissolves in water, forming hydrobromic acid, which is saturated at 68.85% HBr by weight at room temper ...

is added, in contrary to the Markovnikov rule (" anti-Markovnikov"). When cooled to 0 °C, the fast and highly exothermic reaction produces 11-bromoundecanoic acid in 95% yield - the Markovnikov product 10-bromoundecanoic acid is produced in small quantities as a

by-product A by-product or byproduct is a secondary product derived from a production process, manufacturing process or chemical reaction; it is not the primary product or service being produced. A by-product can be useful and marketable or it can be cons ...

. Toluene and unreacted hydrogen bromide are extracted under reduced pressure and reused. :

Bromine exchange of 11-bromoundecanoic acid to 11-aminoundecanoic acid

11-Bromodecanoic acid is mixed at 30 °C with a large excess of 40% aqueous

ammonia Ammonia is an inorganic chemical compound of nitrogen and hydrogen with the chemical formula, formula . A Binary compounds of hydrogen, stable binary hydride and the simplest pnictogen hydride, ammonia is a colourless gas with a distinctive pu ...

solution. When the reaction is complete, water is added and the mixture is heated to 100 °C to remove the excess ammonia. : The acid can be recrystallized from water. For further purification, the hydrochloride of 11-aminoundecanoic acid, which is available by acidification with hydrochloric acid, can be recrystallized from a methanol/ethyl acetate mixture.

Properties

11-Aminoundecanoic acid is a white crystalline and odorless solid with low solubility in water.

Use

By acylation of 11-aminoundecanoic acid with

chloroacetyl chloride Chloroacetyl chloride is a chlorinated acyl chloride. It is a bifunctional compound, making it a useful building block chemical. Production Industrially, it is produced by the carbonylation of methylene chloride, oxidation of vinylidene chlo ...

, chloroacetylamino-11-undecanoic acid can be produced, which acts as a

fungicide Fungicides are pesticides used to kill parasitic fungi or their spores. Fungi can cause serious damage in agriculture, resulting in losses of yield and quality. Fungicides are used both in agriculture and to fight fungal infections in animals, ...

and

insecticide Insecticides are pesticides used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. The major use of insecticides is in agriculture, but they are also used in home and garden settings, i ...

. ''N''-acyl derivatives of 11-aminoundecanoic acid in the form of oligomeric amides have remarkable properties as gelling agents for water and organic solvents.

Monomer for polyamide 11

By far the most important application of 11-aminoundecanoic acid is its use as a monomer for

polyamide 11 Nylon 11 or Polyamide 11 (PA 11) is a polyamide, bioplastic and a member of the nylon family of polymers produced by the polymerization of 11-aminoundecanoic acid. It is produced from castor beans by Arkema under the trade name Rilsan. Nylon 11 ...

(also: nylon-11).

Wallace Carothers Wallace Hume Carothers (; April 27, 1896 – April 29, 1937) was an American chemist, inventor, and the leader of organic chemistry at DuPont, who was credited with the invention of nylon. Carothers was a group leader at the DuPont Experimen ...

, the inventor of polyamide (

nylon 66 Nylon 66 (loosely written nylon 6-6, nylon 6/6, nylon 6,6, or nylon 6:6) is a type of polyamide or nylon. It, and nylon 6, are the two most common for textile and plastic industries. Nylon 66 is made of two monomers each containing six carbon at ...

), is said to have polymerized 11-aminoundecanoic acid as early as 1931. : Although polyamide 11 is derived from a renewable raw material (i.e. biobased), it is not

biodegradable Biodegradation is the breakdown of organic matter by microorganisms, such as bacteria and fungi. It is generally assumed to be a natural process, which differentiates it from composting. Composting is a human-driven process in which biodegrada ...

. Nevertheless, it has the most advantageous ecological profile of comparable thermoplastics.Jim Mason
''Rilsan Polyamide-11 - A success story for sustainable resource based engineering thermoplastics''
, 9. April 2008. Due to its excellent toughness at low temperatures, polyamide 11 can be used at temperatures as low as -70 °C. Its relatively non-polar molecular structure due to the low frequency of amide bonds in the molecule results in low moisture absorption compared to polyamide 6 or polyamide 66. In addition, polyamide 11 has very good chemical stability, e.g. against hydrocarbons, low density, good thermal stability, weather resistance and is easy to process.

References

{{DEFAULTSORT:Aminoundecanoic acid Amino acids