amine: Quick Facts

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Examples of different types of amines.

Ammonia and amines have a slightly flattened trigonal pyramidal shape, with a lone pair of electrons above the nitrogen. In quaternary ammonium salts, this area is occupied by a fourth substituent. Rapid inversion takes place between the enantiomers of amines with chiral nitrogens, but in quaternary ammonium ions such interconversion is not possible.

Diagram showing common functional groups in monomers-amine, carboxylic acid, alcohol, and isocyanate-at the top, and their resulting polymer linkages-amide, ester, and carbamate (urethane)-at the bottom, with color-coded chemical structures and connecting lines illustrating how monomers combine during polymerization.

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Topics

primary amine tertiary amine cadaverine nitrosamine naphthylamine ethylenediamine hexamethylene diamine quaternary ammonium compound morpholine diamine alkaloid guanidine amide urea Capsaicin Choline biotin nitrile oxime isocyanide

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Periodic Table of the elements concept image (chemistry)

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