Chloramines

Chloramines refer to derivatives of ammonia and organic amines wherein one or more N−H bonds have been replaced by N−Cl bonds.^[1][2] Two classes of compounds are considered: inorganic chloramines and organic chloramines. Chloramines are the most widely used members of the halamines.^[3]

Inorganic chloramines

Inorganic chloramines comprise three compounds: monochloramine (NH₂Cl), dichloramine (NHCl₂), and nitrogen trichloride (NCl₃). Monochloramine is of broad significance as a disinfectant for water.^[4]

Organic chloramines

Organic chloramines feature the NCl functional group attached to an organic substituent. Examples include N-chloromorpholine (ClN(CH₂CH₂)₂O), N-chloropiperidine, and N-chloroquinuclidinium chloride.^[7]

Chloramines are commonly produced by the action of sodium hypochlorite on secondary amines:

R₂NH + NaOCl → R₂NCl + NaOH

Tert-butyl hypochlorite can be used instead of bleach:^[8]

R₂NH + t-BuOCl → R₂NCl + t-BuOH

Swimming pools

Chloramines are formed by reaction of chlorine used to disinfect swimming pools with ammonia and urea introduced into the pools by human perspiration, saliva, mucus, urine, and other biologic substances, and by insects and other pests.^[9] Chloramines, especially trichloramine, are responsible for most of the "chlorine smell" of pools, as well as for skin, eye, and respiratory irritation.^[10]

References