4-Aminophenol
4-Aminophenol
Names
Preferred IUPAC name
Other names
p -Aminophenolpara -Aminophenol
Identifiers
385836
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.004.198
EC Number
2926
KEGG
MeSH Aminophenols
UNII
UN number 2512
InChI=1S/C6H7NO/c7-5-1-3-6(8)4-2-5/h1-4,8H,7H2
Y Key:
PLIKAWJENQZMHA-UHFFFAOYSA-N
Y InChI=1/C6H7NO/c7-5-1-3-6(8)4-2-5/h1-4,8H,7H2
Key: PLIKAWJENQZMHA-UHFFFAOYAD
Properties
C 6 H 7 N O
Molar mass g·mol−1
Appearance
Colorless to reddish-yellow crystals
Density 1.13 g/cm3
Melting point 187.5 °C (369.5 °F; 460.6 K)
Boiling point 284 °C (543 °F; 557 K)
1.5 g/100 mL
Solubility
log P 0.04
Acidity (pK a )5.48 (amino; H2 O) 10.30 (phenol; H2 O)[ 2]
Structure
orthorhombic
Thermochemistry
−190.6 kJ/mol
Hazards
GHS labelling
Warning
H302 , H332 , H341 , H410
P201 , P202 , P261 , P264 , P270 , P271 , P273 , P281 , P301+P312 , P304+P312 , P304+P340 , P308+P313 , P312 , P330 , P391 , P405 , P501
NFPA 704 diamond)
Flash point 195 °C (383 °F; 468 K) (cc)
Lethal dose or concentration (LD, LC):
671 mg/kg
Related compounds
Related aminophenols
2-Aminophenol 3-Aminophenol
Related compounds
Aniline Phenol
Except where otherwise noted, data are given for materials in their
standard state (at 25
°C [77
°F], 100
kPa).
Chemical compound
4-Aminophenol (or para -aminophenolp -aminophenolorganic compound with the formula H2 NC6 H4 OH. It is a metabolite of acetaminophen which the body converts to N-arachidonoylphenolamine and this compound is responsible for all or part of acetaminophen's analgesic action[ 3] anticonvulsant effects.[ 4]
Commercially available as a white powder,[ 5] developer for black-and-white film , marketed under the name Rodinal .
Reflecting its slightly hydrophilic character, the white powder is moderately soluble in alcohols and can be recrystallized from hot water. In the presence of a base, it oxidizes readily. The methylated derivatives N -methylaminophenolN ,N -dimethylaminophenol
The compound is one of three isomeric aminophenols, the other two being 2-aminophenol and 3-aminophenol .
Preparation
4-Aminophenol can be prepared by several routes. One route is hydrogenation of 4-nitrophenol over Raney nickel .[ 6]
HOC6 H4 NO2 + 3 H2 → HOC6 H4 NH2 + 2 H2 O The nitrophenol can also be reduced by iron or by stannous chloride .[ 7] [ 8]
4-Aminophenol can be produced by reduction of nitrobenzene via the intermediate phenylhydroxylamine , which spontaneously rearranges to 4-aminophenol.[ 9] [ 6]
C6 H5 NHOH → HOC6 H4 NH2 References
↑ Nomenclature of Organic Chemistry : IUPAC Recommendations and Preferred Names 2013 (Blue Book) . Cambridge: The Royal Society of Chemistry . 2014. p. 690. doi :10.1039/9781849733069-FP001 . ISBN 978-0-85404-182-4 ↑ Haynes, William M., ed. (2016). CRC Handbook of Chemistry and Physics ed.). CRC Press . pp. 5– 89. ISBN 978-1498754286 ↑ Ottani A, Leone S, Sandrini M, Ferrari A, Bertolini A (February 2006). "The analgesic activity of paracetamol is prevented by the blockade of cannabinoid CB1 receptors". European Journal of Pharmacology . 531 (1– 3): 280– 281. doi :10.1016/j.ejphar.2005.12.015 . PMID 16438952 . ↑ Deshpande LS, DeLorenzo RJ (January 2011). "Acetaminophen inhibits status epilepticus in cultured hippocampal neurons" . NeuroReport . 22 (1): 15– 18. doi :10.1097/WNR.0b013e3283413231 . PMC 3052417 PMID 21037491 . ↑ CRC Handbook of Chemistry and Physics 65th Ed.1 2 Mitchell, Stephen C.; Waring, Rosemary H. (2000). "Aminophenols". Ullmann's Encyclopedia of Industrial Chemistry . doi :10.1002/14356007.a02_099 . ISBN 978-3-527-30385-4 ↑ US2998450A , Godfrey, Wilbert & De, Angelis John, "Process of preparing nu-acetyl-p-amino phenol", issued 1961-08-29 ↑ Bellamy, F. D.; Ou, K. (1984-01-01). "Selective reduction of aromatic nitro compounds with stannous chloride in non acidic and non aqueous medium" Tetrahedron Letters . 25 (8): 839– 842. doi :10.1016/S0040-4039(01)80041-1 . ISSN 0040-4039 . ↑ Polat, K.; Aksu, M.L.; Pekel, A.T. (2002), "Electroreduction of nitrobenzene to p-aminophenol using voltammetric and semipilot scale preparative electrolysis techniques", Journal of Applied Electrochemistry , 32 (2), Kluwer Academic Publishers: 217– 223, doi :10.1023/A:1014725116051 , S2CID 54499902 ↑ Ellis, Frank (2002). Paracetamol: a curriculum resource . Cambridge: Royal Society of Chemistry. ISBN 0-85404-375-6 ↑ Anthony S. Travis (2007). "Manufacture and uses of the anilines: A vast array of processes and products". In Zvi Rappoport (ed.). The chemistry of Anilines Part 1 764 . ISBN 978-0-470-87171-3 ↑ Elmar Friderichs; Thomas Christoph; Helmut Buschmann. "Analgesics and Antipyretics". Ullmann's Encyclopedia of Industrial Chemistry doi :10.1002/14356007.a02_269.pub2 . ISBN 978-3-527-30673-2 ↑ F. B. Dains, Floyd Eberly (1935). "p-Iodophenol". Organic Syntheses . 15 : 39. doi :10.15227/orgsyn.015.0039 .
