In the chemical sciences, methylation denotes the addition of a methyl group on a substrate, or the substitution of an atom by a methyl group. Methylation is a form of alkylation, with a methyl group replacing a hydrogen atom. These terms are commonly used in chemistry, biochemistry, soil science, and the biological sciences.
Hydroxylamine is an inorganic compound with the formula NH2OH. The material is a white crystalline, hygroscopic compound. Hydroxylamine is almost always provided and used as an aqueous solution. It is consumed almost exclusively to produce Nylon-6. It is also an intermediate in biological nitrification. The oxidation of NH3 to hydroxylamine is a step in biological nitrification.
Hydroxycarbamide, also known as hydroxyurea, is a medication used in sickle-cell disease, essential thrombocythemia, chronic myelogenous leukemia and cervical cancer. In sickle-cell disease it increases fetal hemoglobin and decreases the number of attacks. It is taken by mouth.
The Cope reaction or Cope elimination, developed by Arthur C. Cope, is an elimination reaction of the N-oxide to form an alkene and a hydroxylamine.
The Weinreb–Nahm ketone synthesis is a chemical reaction used in organic chemistry to make carbon–carbon bonds. It was discovered in 1981 by Steven M. Weinreb and Steven Nahm as a method to synthesize ketones. The original reaction involved two subsequent nucleophilic acyl substitutions: the conversion of an acid chloride with N,O-Dimethylhydroxylamine, to form a Weinreb–Nahm amide, and subsequent treatment of this species with an organometallic reagent such as a Grignard reagent or organolithium reagent. Nahm and Weinreb also reported the synthesis of aldehydes by reduction of the amide with an excess of lithium aluminum hydride.
In chemistry, an amine oxide, also known as an amine N-oxide or simply N-oxide, is a chemical compound that contains the functional group R3N+−O−, a nitrogen-oxygen coordinate covalent bond with three additional hydrogen and/or substituent-group side chains attached to N. Sometimes it is written as R3N→O or, incorrectly, as R3N=O.
In organic chemistry, a nitrone is a functional group consisting of an N-oxide of an imine. The general structure is R2C=N+O−R’, where R’ is not a hydrogen. A nitrone is a 1,3-dipole, and is used in 1,3-dipolar cycloadditions. Other reactions of nitrones are known, including formal [3+3] cycloadditions to form 6-membered rings, as well as formal [5+2] cycloadditions to form 7-membered rings.
In organic chemistry, the Baudisch reaction is a process for the synthesis of nitrosophenols using metal ions. Although the products are of limited value, the reaction is of historical interest as an example of metal-promoted functionalization of aromatic substrates.
N-Hydroxysuccinimide (NHS) is an organic compound with the formula (CH2CO)2NOH. It is a white solid that is used as a reagent for preparing active esters in peptide synthesis. It can be synthesized by heating succinic anhydride with hydroxylamine or hydroxylamine hydrochloride.
The Stieglitz rearrangement is a rearrangement reaction in organic chemistry which is named after the American chemist Julius Stieglitz (1867–1937) and was first investigated by him and Paul Nicholas Leech in 1913. It describes the 1,2-rearrangement of trityl amine derivatives to triaryl imines. It is comparable to a Beckmann rearrangement which also involves a substitution at a nitrogen atom through a carbon to nitrogen shift. As an example, triaryl hydroxylamines can undergo a Stieglitz rearrangement by dehydration and the shift of a phenyl group after activation with phosphorus pentachloride to yield the respective triaryl imine, a Schiff base.
Hydroxylammonium sulfate (NH3OH)2SO4, is the sulfuric acid salt of hydroxylamine. It is primarily used as an easily handled form of hydroxylamine, which is explosive when pure.
Deoxyepinephrine, also known by the common names N-methyldopamine and epinine, is an organic compound and natural product that is structurally related to the important neurotransmitters dopamine and epinephrine. All three of these compounds also belong to the catecholamine family. The pharmacology of epinine largely resembles that of its "parent", dopamine. Epinine has been found in plants, insects and animals. It is also of significance as the active metabolic breakdown product of the prodrug ibopamine, which has been used to treat congestive heart failure.
Acetone oxime (acetoxime) is the organic compound with the formula (CH3)2CNOH. It is the simplest example of a ketoxime. It is a white crystalline solid that is soluble in water, ethanol, ether, chloroform, and ligroin. It is used as a reagent in organic synthesis.
Methoxyamine is the organic compound with the formula CH3ONH2. Also called O-methylhydroxylamine, it a colourless volatile liquid that is soluble in polar organic solvent and in water. It is a derivative of hydroxylamine with the hydroxyl hydrogen replaced by a methyl group. Alternatively, it can be viewed as a derivative of methanol with the hydroxyl hydrogen replaced by an amino group. It is an isomer of N-methylhydroxylamine and aminomethanol. It decomposes in an exothermic reaction (-56 kJ/mol) to methane and azanone unless stored as a hydrochloride salt.
N-Methylhydroxylamine or methylhydroxylamine is a hydroxylamine derivative with a methyl group replacing one of the hydrogens of the amino group. It is an isomer of methoxyamine and aminomethanol. It decomposes in an exothermic reaction into methane and azanone unless stored as a hydrochloride salt.
Hydroxylamine-O-sulfonic acid (HOSA) is the inorganic compound with molecular formula H3NO4S that is formed by the sulfonation of hydroxylamine with oleum. It is a white, water-soluble and hygroscopic, solid, commonly represented by the condensed structural formula H2NOSO3H, though it actually exists as a zwitterion and thus is more accurately represented as +H3NOSO3−. It is used as a reagent for the introduction of amine groups (–NH2), for the conversion of aldehydes into nitriles and alicyclic ketones into lactams (cyclic amides), and for the synthesis of variety of nitrogen-containing heterocycles.
N-Hydroxyphthalimide is the N-hydroxy derivative of phthalimide. The compound can be utilized as a catalyst for oxidation reactions, in particular for the selective oxidation with molecular oxygen under mild conditions.
Methyldiazinol is a synthetic and orally active androgen/anabolic steroid (AAS) which was never marketed. It is a 17α-methylated derivative of dihydrotestosterone (DHT); specifically, it is the C3 azi analogue of mestanolone (17α-methyl-DHT). The drug has been found to possess a high ratio and dissociation of myotrophic to androgenic activity; relative to methyltestosterone, its ratio was 15 (3:0.2), among the highest observed.
Formaldoxime is the organic compound with the formula H2C=NOH. It is the oxime of formaldehyde. A colorless liquid, the pure compound tends to polymerize into a trimer. Aqueous solutions are stable as is the hydrochloride. It is a reagent in organic synthesis for the conversion of aryl diazonium salts to aryl aldehydes.
