aminogrupp

Aminogrupp, also called the amino group, is a functional group in organic chemistry characterized by a nitrogen atom bonded to one or more carbon-containing substituents and bearing hydrogen atoms. In its simplest form the primary amino group has the formula R-NH2; secondary and tertiary amino groups have the forms R-NH-R' and R3N. The amino group is polar and basic: the nitrogen lone pair accepts a proton to form the ammonium ion R-NH3+. For most aliphatic amines, the conjugate acid has a pKa around 9–11, making them predominantly protonated in acidic solutions and largely unprotonated at higher pH.

Aminogrupp is widespread in organic and biochemistry. It is a component of amino acids, where the amino group is attached to the α-carbon and is protonated under physiological conditions; it also appears in various amines, including methylamine (R-NH2) and aniline (aryl-NH2). The group enables hydrogen bonding and acts as a nucleophile in many reactions, including acylation to form amides and alkylation to form substituted amines. Aromatic amines can undergo diazotization to give diazonium salts, key intermediates in aromatic substitution.

In biology and materials science, aminogrupp contributes to solubility, reactivity, and binding properties. It is a central feature in drug design, catalysis, and polymer chemistry, where the presence and pKa of the amino group influence activity, stability, and interactions with targets.