Skeletal formula of n-butylamine
Ball-and-stick model of the n-butylamine molecule
Preferred IUPAC name
Other names
  • 1-Aminobutane
  • 1-Butanamine
  • Monobutylamine
3D model (JSmol)
Abbreviations NBA
ECHA InfoCard 100.003.364 Edit this at Wikidata
EC Number
  • 203-699-2
MeSH n-butylamine
RTECS number
  • EO29750002
UN number 1125
  • InChI=1S/C4H11N/c1-2-3-4-5/h2-5H2,1H3 checkY
Molar mass 73.139 g·mol−1
Appearance Colorless liquid
Odor fishy, ammoniacal
Density 740 mg ml−1
Melting point −49 °C; −56 °F; 224 K
Boiling point 77 to 79 °C; 170 to 174 °F; 350 to 352 K
log P 1.056
Vapor pressure 9.1 kPa (at 20 °C)
570 μmol Pa−1 kg−1
Basicity (pKb) 3.22
-58.9·10−6 cm3/mol
Viscosity 500 µPa s (at 20 °C)
188 J K−1 mol−1
−128.9–−126.5 kJ mol−1
−3.0196–−3.0174 MJ mol−1
GHS labelling:
GHS02: Flammable GHS05: Corrosive GHS07: Exclamation mark
H225, H302, H312, H314, H332
P210, P280, P305+P351+P338, P310
NFPA 704 (fire diamond)
Flash point −7 °C (19 °F; 266 K)
312 °C (594 °F; 585 K)
Explosive limits 1.7–9.8%
Lethal dose or concentration (LD, LC):
  • 366 mg kg−1 (oral, rat)
  • 626 mg kg−1 (dermal, rabbit)
  • 430 mg kg−1 (oral, mouse)
  • 430 mg kg−1 (oral, guinea pig)
4000 ppm (rat, 4 hr)
263 ppm (mouse, 2 hr)[2]
NIOSH (US health exposure limits):
PEL (Permissible)
C 5 ppm (15 mg/m3) [skin][1]
REL (Recommended)
C 5 ppm (15 mg/m3) [skin][1]
IDLH (Immediate danger)
300 ppm[1]
Safety data sheet (SDS) hazard.com
Related compounds
Related alkanamines
Related compounds
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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n-Butylamine is an organic compound (specifically, an amine) with the formula CH3(CH2)3NH2. This colourless liquid is one of the four isomeric amines of butane, the others being sec-butylamine, tert-butylamine, and isobutylamine. It is a liquid having the fishy, ammonia-like odor common to amines. The liquid acquires a yellow color upon storage in air. It is soluble in all organic solvents. Vapors heavier than air and it produces toxic oxides of nitrogen during combustion.[3]

Synthesis and reactions[]

It is produced by the reaction of ammonia and alcohols over alumina:

CH3(CH2)3OH + NH3 → CH3(CH2)3NH2 + H2O

n-Butylamine is a weak base. The pKa of [CH3(CH2)3NH3]+ is 10.78.[4]

n-Butylamine exhibits reactions typical of other simple alkyl amines, i.e., alkylation, acylation, condensation with carbonyls. It forms complexes with metal ions, examples being cis- and trans-[PtI2(NH2Bu)2].[5]


This compound is used as an ingredient in the manufacture of pesticides (such as thiocarbazides), pharmaceuticals, and emulsifiers. It is also a precursor for the manufacture of N,N′-dibutylthiourea, a rubber vulcanization accelerator, and n-butylbenzenesulfonamide, a plasticizer of nylon. It is used in the synthesis of fengabine, the fungicide benomyl, and butamoxane, and the antidiabetic tolbutamide.[6]

Butylamine is a precursor to the fungicide benomyl.


The LD50 to rats through the oral exposure route is 366 mg/kg.[7]

In regards to occupational exposures to n-butylamine, the Occupational Safety and Health Administration and National Institute for Occupational Safety and Health have set occupational exposure limits at a ceiling of 5 ppm (15 mg/m3) for dermal exposure.[8]


  1. ^ a b c NIOSH Pocket Guide to Chemical Hazards. "#0079". National Institute for Occupational Safety and Health (NIOSH).
  2. ^ a b "N-Butylamine". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
  3. ^ PubChem. "Butylamine". pubchem.ncbi.nlm.nih.gov. Retrieved 2022-02-15.
  4. ^ H. K. Hall, Jr. (1957). "Correlation of the Base Strengths of Amines". J. Am. Chem. Soc. 79 (20): 5441–5444. doi:10.1021/ja01577a030.
  5. ^ Rochon, Fernande D.; Buculei, Viorel (2004). "Multinuclear NMR Study and Crystal Structures of Complexes of the Types cis- and trans-Pt(amine)2I2". Inorganica Chimica Acta. 357 (8): 2218–2230. doi:10.1016/j.ica.2003.10.039.
  6. ^ Karsten Eller, Erhard Henkes, Roland Rossbacher, Hartmut Höke, "Amines, Aliphatic" Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005.doi:10.1002/14356007.a02_001
  7. ^ "n-Butylamine MSDS" (PDF). Archived from the original (PDF) on 2013-11-12. Retrieved 2013-11-12.
  8. ^ CDC - NIOSH Pocket Guide to Chemical Hazards

External links[]