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IUPAC name
Other names
3D model (JSmol)
ECHA InfoCard 100.003.300
EC Number 203-629-0
RTECS number GX0700000
Molar mass 99.17
Appearance clear to yellowish liquid
Odor strong, fishy, amine odor
Density 0.8647 g/cm3
Melting point −17.7 °C (0.1 °F; 255.5 K)
Boiling point 134.5 °C (274.1 °F; 407.6 K)
Solubility very soluble in ethanol, oil
miscible in ethers, acetone, esters, alcohol, ketones
Vapor pressure 11 mmHg (20° C)[2]
Acidity (pKa) 10.64[3]
S-phrases (outdated) S36 S37 S39
R/S statement (outdated) R21 R23 R25 R36 R37 R38 R41
NFPA 704
Flammability code 3: Liquids and solids that can be ignited under almost all ambient temperature conditions. Flash point between 23 and 38 °C (73 and 100 °F). E.g., gasoline Health code 3: Short exposure could cause serious temporary or residual injury. E.g., chlorine gas Reactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogen Special hazards (white): no codeNFPA 704 four-colored diamond
Flash point 28.6 °C (83.5 °F; 301.8 K)
293 °C (559 °F; 566 K)
Explosive limits 1.5%-9.4%[2]
Lethal dose or concentration (LD, LC):
156 mg/kg (rat, oral)
US health exposure limits (NIOSH):
PEL (Permissible)
REL (Recommended)
TWA 10 ppm (40 mg/m3)[2]
IDLH (Immediate danger)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Cyclohexylamine is an organic compound, belonging to the aliphatic amine class. It is a colorless liquid, although like many amines, samples are often colored due to contaminants. It has a fishy odor and is miscible with water. Like other amines, it is a weak base, compared to strong bases such as NaOH, but it is a stronger base than its aromatic analog, aniline.

It is a useful intermediate in the production of many other organic compounds. It is a metabolite of cyclamate.


Cyclohexylamine is produced by two routes, the main one being hydrogenation of aniline using cobalt or nickel catalysts:[4]

Cyclohexylamine catalytical synthesis from aniline hydrogenation upon high pressure and temperature.

It is also prepared by alkylation of ammonia using cyclohexanol.


Cyclohexylamine is used as an intermediate in synthesis of other organic compounds. It is the precursor to sulfenamide-based reagents used as accelerators for vulcanization. It is a building block for pharmaceuticals (e.g., mucolytics, analgesics, and bronchodilators). The amine itself is an effective corrosion inhibitor. Some sweeteners are derived from this amine, notably cyclamate. The herbicide hexazinone and the anesthetic hexylcaine are derived from cyclohexylamine.[4]


LD50 (rat; p.o.) = 0.71 ml/kg[5]


It is flammable, with flash point at 28.6 °C. It is toxic by both ingestion and inhalation; the inhalation itself may be fatal. It readily absorbs through skin, which it irritates. It is corrosive. Cyclohexylamine is listed as an extremely hazardous substance as defined by Section 302 of the U.S. Emergency Planning and Community Right-to-Know Act. It has been used as a flushing aid in the printing ink industry.[6]

In regards to occupational exposures, the National Institute for Occupational Safety and Health has suggested workers not be exposed to a recommended exposure limit of over 10 ppm (40 mg/m3) over an eight-hour workshift.[2]


  1. ^ Merck Index, 11th Edition, 2735.
  2. ^ a b c d e f "NIOSH Pocket Guide to Chemical Hazards #0168". National Institute for Occupational Safety and Health (NIOSH). 
  3. ^ H. K. Hall, J. Am. Chem. Soc. (1957) 79 5441.
  4. ^ a b Karsten Eller, Erhard Henkes, Roland Rossbacher, Hartmut Höke "Amines, Aliphatic" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005. doi:10.1002/14356007.a02_001
  5. ^ The Merck Index, 10th Ed. (1983) p.392, Rahway: Merck & Co.
  6. ^ Apps, E. A. (1958). Printing Ink Technology. London: Leonard Hill [Books] Limited. pp. ix.