In organic chemistry, amines (, UK also ) are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia (NH3), wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group (these may respectively be called alkylamines and arylamines; amines in which both types of substituent are attached to one nitrogen atom may be called alkylarylamines). Important amines include amino acids, biogenic amines, trimethylamine, and aniline; see Category:Amines for a list of amines. Inorganic derivatives of ammonia are also called amines, such as monochloramine (NClH2).
The Miller–Urey experiment was a chemical experiment that simulated the conditions thought at the time (1952) to be present on the early, prebiotic Earth and tested the chemical origin of life under those conditions. The experiment at the time supported Alexander Oparin's and J. B. S. Haldane's hypothesis that putative conditions on the primitive Earth favored chemical reactions that synthesized more complex organic compounds from simpler inorganic precursors. Considered to be the classic experiment investigating abiogenesis, it was performed in 1952 by Stanley Miller, supervised by Harold Urey at the University of Chicago, and published the following year.
Urea, also known as carbamide, is an inorganic compound with chemical formula CO(NH2)2. This amide has two –NH2 groups joined by a carbonyl (C=O) functional group.
In organic chemistry, an aldehyde is an organic compound containing a functional group with the structure R−CH=O. The functional group itself can be referred to as an aldehyde but can also be classified as a formyl group. Aldehydes are common and play important roles in the technology and biological spheres.
Formaldehyde ( fər-MAL-də-hide, alsofor-) (systematic name methanal) is a naturally occurring organic compound with the formula CH2O (H−CHO). The pure compound is a pungent-smelling colourless gas that polymerises spontaneously into paraformaldehyde (refer to section Forms below), hence it is stored as an aqueous solution (formalin), which is also used to store animal specimens. It is the simplest of the aldehydes (R−CHO). The common name of this substance comes from its similarity and relation to formic acid.
A carbamate is a category of organic compounds that is formally derived from carbamic acid (NH2COOH). The term includes organic compounds (e.g., the ester ethyl carbamate), formally obtained by replacing one or more of the hydrogen atoms by other organic functional groups; as well as salts with the carbamate anion H
2NCOO−
(e.g. ammonium carbamate).
Ethanolamine is an organic chemical compound with the formula HOCH
2CH
2NH
2 or C
2H
7NO. The molecule is bifunctional, containing both a primary amine and a primary alcohol. Ethanolamine is a colorless, viscous liquid with an odor reminiscent of ammonia. ETA molecules are a component in the formation of cellular membranes and are thus a molecular building block for life. It was thought to exist only on Earth and on certain asteroids, but in 2021 evidence was found that ETA molecules exist in interstellar space.
Dehydrogenation is the chemical reaction that involves the removal of hydrogen, usually from an organic molecule. It is the reverse of hydrogenation. Dehydrogenation is important, both as a useful reaction and a serious problem. At its simplest, it is useful way of converting alkanes, which are relatively inert and thus low-valued, to olefins, which are reactive and thus more valuable. Alkenes are precursors to aldehydes, alcohols, polymers, and aromatics. As a problematic reaction, the fouling and inactivation of many catalysts arises via coking, which is the dehydrogenative polymerization of organic substrates.
The Mannich reaction is a three-component organic reaction that involves the amino alkylation of an acidic proton next to a carbonyl functional group by formaldehyde and a primary or secondary amine or ammonia. The final product is a β-amino-carbonyl compound also known as a Mannich base. Reactions between aldimines and α-methylene carbonyls are also considered Mannich reactions because these imines form between amines and aldehydes. The reaction is named after Carl Mannich.
A hemiaminal (also carbinolamine) is a functional group or type of chemical compound that has a hydroxyl group and an amine attached to the same carbon atom: -C(OH)(NR2)-. R can be hydrogen or an alkyl group. Hemiaminals are intermediates in imine formation from an amine and a carbonyl by alkylimino-de-oxo-bisubstitution. Hemiaminals can be viewed as a blend of aminals and geminal diol. They are a special case of amino alcohols.
An aminal or aminoacetal is a functional group or type of organic compound that has two amine groups attached to the same carbon atom: -C(NR2)(NR2)-. (As is customary in organic chemistry, R can represent hydrogen or an alkyl group). A common aminal is bis(dimethylamino)methane, a colorless liquid that is prepared by the reaction of dimethylamine and formaldehyde:
Sulfamic acid, also known as amidosulfonic acid, amidosulfuric acid, aminosulfonic acid, sulphamic acid and sulfamidic acid, is a molecular compound with the formula H3NSO3. This colourless, water-soluble compound finds many applications. Sulfamic acid melts at 205 °C before decomposing at higher temperatures to water, sulfur trioxide, sulfur dioxide and nitrogen.
Acetaldehyde ammonia trimer is a chemical compound described by the formula (CH3CHNH)3. The pure material is colourless but samples often appear light yellow or slightly beige due to the degradation by oxidation. It is hygroscopic, and can be found in a trihydrate form.
Carbamic acid, which might also be called aminoformic acid or aminocarboxylic acid, is the chemical compound with the formula H2NCOOH. It can be obtained by the reaction of ammonia NH3 and carbon dioxide CO2 at very low temperatures, which also yields an equal amount of ammonium carbamate [NH4]+[NH2CO2]−. The compound is stable only up to about 250 K (−23 °C); at higher temperatures it decomposes into those two gases. The solid apparently consists of dimers, with the two molecules connected by hydrogen bonds between the two carboxyl groups –COOH.
Methanediol, also known as formaldehyde monohydrate or methylene glycol, is an organic compound with chemical formula CH2(OH)2. It is the simplest geminal diol, and the simplest sugar alcohol. In aqueous solutions it coexists with oligomers (short polymers). The compound is closely related and convertible to the industrially significant derivatives paraformaldehyde ((CH2O)n), formaldehyde (H2C=O), and 1,3,5-trioxane ((CH2O)3).
Alkanolamines are chemical compounds that contain both hydroxyl (-OH) and amino (-NH2, -NHR, and -NR2) functional groups on an alkane backbone. The term alkanolamine is a broad class term that is sometimes used as a subclassification.
The amino radical, •
NH
2, also known as the aminyl radical or azanyl radical, is the neutral form of the amide ion (NH−
2). Aminyl are highly reactive and consequently short lived like most radicals; however, they form an important part of nitrogen chemistry. In sufficiently high concentration, amino radicals dimerise to form hydrazine. While NH2 as a functional group is common in nature, forming a part of many compounds (e.g. the phenethylamines), the radical cannot be isolated in its free form.
In chemistry, an imidic acid is any molecule that contains the -C(=NH)-OH functional group. It is the tautomer of an amide and the isomer of an oxime.
Nitrilotriacetonitrile (NTAN) is a precursor for nitrilotriacetic acid, for tris(2-aminoethyl)amine and for the epoxy resin crosslinker aminoethylpiperazine.
The nitro-Mannich reaction is the nucleophilic addition of a nitroalkane to an imine, resulting in the formation of a beta-nitroamine. With the reaction involving the addition of an acidic carbon nucleophile to a carbon-heteroatom double bond, the nitro-Mannich reaction is related to some of the most fundamental carbon-carbon bond forming reactions in organic chemistry, including the aldol reaction, Henry reaction and Mannich reaction.
