Reactive Group Datasheet

Amines, Phosphines, and Pyridines

Amines, phosphines, and pyridines are generally high-boiling liquids or solids at room temperature and are combustible, but not highly flammable. Methylamine is an exception, because it is a gas with a wide flammability range. The combustion of amines yields noxious NOx gases. Phosphines are a bit more reactive and may ignite spontaneously on contact with air at or about 100°C.
Amines, phosphines, and pyridines are chemical bases. They neutralize acids to form salts plus water. These acid-base reactions are exothermic. The amount of heat that is evolved per mole of base in a neutralization is largely independent of the strength of the base. These chemicals may be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, strong acids, and acid halides. Flammable gaseous hydrogen is generated in combination with strong reducing agents, such as hydrides.
Variable. Some are very poisonous; others are only slightly toxic. Many of these are skin irritants. Some are known sensitizers for small populations of humans and serve to cause chemically induced allergic reactions. The effects of such reactions can be dramatic at rather low concentrations.
Other Characteristics
Amines are organic compounds derived from ammonia (NH3) by the replacement of one or more of the three hydrogen atoms of NH3 with an organic group R. The R group may be either aromatic or aliphatic. Aromatic amines contain at least one aromatic R group; aliphatic amines contain all aliphatic groups. Pyridines, triazines, and other nitrogen-based heterocycles are related to amines and are known as heterocyclic aromatic hydrocarbons, with C-N-C bonds forming part of an aromatic ring. Phosphines are related to amines by replacing the nitrogen with phosphorus. Many amines, phosphines, and pyridines have unpleasantly fishy or putrid odors.
Methylamine, triethanolamine, hexamethylenetetramine, cyclohexylamine, pyridine, diphenylamine, ethylenediamine, 1-ethylpiperidine, benzimdazole, triazine, triphenylphosphine, dimethylphosphine.