Introduction
Amino alcohols are an important class of organic compounds which contain both amine (-NH2, -NHR, and -NR) and hydroxyl (-OH) functional groups. They are a kind of high value-added fine chemical products downstream of formaldehyde in chemical industry field. Formaldehyde and nitro-alkane can occur a condensation to produce a nitroalcohol then this nitroalcohol can be reduced to obtain a series of amino alcohols. In another way, they can be generated often by the reaction of amines with epoxides.
Fig.1. Amino alcohols compounds
Most amino alcohols are highly water-soluble, because they contain hydroxyl and amino which are hydrophilic groups. Amino alcohols generally have high boiling point, while they have low vapor pressure at normal temperature and pressure. All amino alcohols exhibit the dual chemical reactivity of amines and alcohols, which can be applied in organic reactions design. Amino alcohols are chemically corrosive to copper and aluminum, but not corrosive to iron. They can react with inorganic acids to produce ammonium salts, as well as can be used as ammoniation reagent. With these unique properties, amino alcohols can provide a variety of applications such as solvents, synthetic intermediates, and high-boiling bases in industry.
Applications
Medicine: Most amino acids and peptides contain both hydroxyl and amino groups. In general, amino acids can be converted to corresponding synthetically important amino alcohols, which form the building unit towards making several bioactive molecules. Amino alcohol derivatives are currently being studied for their antimicrobial and antifungal activities, and in the modulation of the physiochemical properties of drug molecules.
Fig.2. Biologically Active β-Amino Alcohols
(J. Am. Chem. Soc. 2002, 124, 10451-10455.)Asymmetric catalysis: β-Amino alcohols also play an important role as chiral ligands and chiral auxiliaries in asymmetric catalysis, most commonly derived from natural sources. The amino alcohols are generally derivatized to improve their chelating ability or to increase their steric directing effect.
Fig.3. Examples of β-Amino Alcohol-containing Chiral Ligands and Auxiliaries
(J. Am. Chem. Soc. 2000, 122, 1806-1807)Catalysts: Amino alcohols can be used as catalysts to synthesize polymer materials. Because they have a strong ability to absorb carbon dioxide, they can be used as decarboxylation catalysts.
Emulgator: Amino alcohols fatty acid soap is a particularly good industrial emulsifier, which can be used to produce polishes, cosmetic emulsions and functional fluids (such as metal cooling lubricant).
Water treatment agents: Amino alcohols can have a good anti-corrosive effect on steel components. For example, aminomethyl propanol (AMP) is used as a boiler water treatment agent, because it can absorb effectively carbon dioxide to protect the steel parts of steam line from corrosion.
