Acetaminophen

• Formula: C₈H₉NO₂
• Molecular weight: 151.1626
• IUPAC Standard InChI: InChI=1S/C8H9NO2/c1-6(10)9-7-2-4-8(11)5-3-7/h2-5,11H,1H3,(H,9,10) Copy

  
• IUPAC Standard InChIKey: RZVAJINKPMORJF-UHFFFAOYSA-N Copy
• CAS Registry Number: 103-90-2
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
  The 3d structure may be viewed using Java or Javascript.
• Other names: Acetamide, N-(4-hydroxyphenyl)-; Acetanilide, 4'-hydroxy-; p-(Acetylamino)phenol; p-Acetamidophenol; p-Hydroxyacetanilide; p-Hydroxyphenolacetamide; Abensanil; Acamol; Acetagesic; Acetalgin; Acetaminofen; Algotropyl; Alvedon; Amadil; Anaflon; Anelix; Apamid; Apamide; APAP; Ben-u-Ron; Bickie-mol; Calpol; Cetadol; Clixodyne; Dial-a-gesic; Dirox; Dymadon; Eneril; Febrilix; Febro-Gesic; Febrolin; Fendon; Finimal; Hedex; Homoolan; Lestemp; Liquagesic; Lonarid; Lyteca; Lyteca Syrup; Multin; N-(4-Hydroxyphenyl)acetamide; N-Acetyl-p-aminophenol; N-Acetyl-4-aminophenol; Napafen; Naprinol; Nobedon; NAPA; NAPAP; Pacemo; Panadol; Panets; Paracetamol; Paracetamole; Paracetanol; Parmol; Pedric; Phendon; Pyrinazine; Tabalgin; Temlo; Tempanal; Tempra; Tralgon; Tussapap; Tylenol; Valadol; Valgesic; 4-Acetamidophenol; 4-Acetaminophenol; 4-Hydroxyacetanilide; 4'-Hydroxyacetanilide; Accu-Tap; Acetamide, N-(p-hydroxyphenyl)-; Alpiny; Anapap; Anhiba; Apadon; Datril; Dimindol; Dularin; Dypap; Elixodyne; Febridol; Febrinol; G 1; Gelocatil; Injectapap; Janupap; Korum; Nealgyl; Nebs; Neotrend; NCI-C55801; Painex; Paracet; Paracetamol DC; Parapan; Phenol, p-acetamido-; Rivalgyl; Servigesic; St. Joseph Fever Reducer; SK-Apap; Tapar; Alpinyl; Doliprane; Enelfa; Exdol; 4-Hydroxyanilid kyseliny octove; Momentum; Panex; Panofen; Paracetamolo; Paraspen; Banesin; Phenaphen; Captin; Dafalgan; Disprol; Dolprone; Eu-Med; Ortensan; Paldesic; Panaleve; Panasorb; Parelan; Pasolind N; Salzone; 4-(Acetylamino)phenol; 4-(N-Acetylamino)phenol; Acenol; Biocetamol; Citramon P; Claratal; Cyclopam; Daga; Daphalgan; Minoset; N-Acetyl-4-hydroxyaniline; Pacemol; Panodil; Pinex; Pyral; Resfenol; Resprin; Vermidon; p-Acetoaminophen; N-(p-Hydroxyphenyl) acetamide; Actifed Plus (Salt/Mix); Anexsia (Salt/Mix); Aspirin-Free Anacin (Salt/Mix); Bayer Select Allergy-Sinus (Salt/Mix); Bayer Select Head Cold (Salt/Mix); Bayer Select Menstrual Multi-Symptom (Salt/Mix); Bayer Select Sinus Pain Relief (Salt/Mix); Contac Cough & Sore Throat Formula (Salt/Mix); Coricidin (Salt/Mix); Coricidin D (Salt/Mix); Coricidin Sinus (Salt/Mix); DHCplus (Salt/Mix); Darvocet-N (Salt/Mix); Demilets (Salt/Mix); Drixoral Cold & Flu (Salt/Mix); Drixoral Sinus (Salt/Mix); Empracet (Salt/Mix); Endecon (Salt/Mix); Hy-Phen (Salt/Mix); Hycomine Compound (Salt/Mix); Intensin (Salt/Mix); Liquiprin (Salt/Mix); Midol Maximum Strength (Salt/Mix); Midol PM Night Time Formula (Salt/Mix); Midol Regular Strength (Salt/Mix); Midol Teen Formula (Salt/Mix); Naldegesic (Salt/Mix); Ornex Severe Cold Formula (Salt/Mix); Percocet (Salt/Mix); Propacet (Salt/Mix); Quiet World (Salt/Mix); Rhinex D-Lay Tablets (Salt/Mix); Robitussin Night Relief (Salt/Mix); Sine-Aid, Maximum Strength (Salt/Mix); Sine-Off Sinus Medicine Caplets (Salt/Mix); Sinubid (Salt/Mix); St. Joseph Cold Tablets for Children (Salt/Mix); Sudafed Cold and Cough (Salt/Mix); Sudafed Severe Cold Formula (Salt/Mix); Sudafed Sinus (Salt/Mix); Supac (Salt/Mix); Talacen (Salt/Mix); TheraFlu (Salt/Mix); Triaminic Sore Throat Formula (Salt/Mix); Tylenol Allergy Sinus (Salt/Mix); Tylox (Salt/Mix); Vanquish (Salt/Mix); Vicodin (Salt/Mix); Zydone (Salt/Mix); Wygesic (Salt/Mix)
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• Information on this page:
  • Phase change data
  • IR Spectrum
  • THz IR spectrum
  • UV/Visible spectrum
  • References
  • Notes
• Other data available:
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • Gas Chromatography
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Phase change data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos

Enthalpy of vaporization

Enthalpy of fusion

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

• SOLID (NUJOL MULL); PERKIN-ELMER 21 (GRATING) $$SPECTRAL CONTAMINATION DUE TO OIL AROUND 2850 CM^-1; 2 cm^-1 resolution

Data compiled by: Timothy J. Johnson, Tanya L. Myers, Yin-Fong Su, Russell G. Tonkyn, Molly Rose K. Kelly-Gorham, and Tyler O. Danby

• solid; Bruker Tensor 37 FTIR; 0.96450084 cm^-1 resolution

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

• gas; HP-GC/MS/IRD

THz IR spectrum

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Edwin J. Heilweil and Matthew B. Campbell

Condensed Phase Spectrum

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Additional Data

UV/Visible spectrum

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Victor Talrose, Alexander N. Yermakov, Alexy A. Usov, Antonina A. Goncharova, Axlexander N. Leskin, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

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Additional Data

References

Go To: Top, Phase change data, IR Spectrum, THz IR spectrum, UV/Visible spectrum, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Manzo and Ahumanda, 1990
Manzo, R.H.; Ahumanda, A.A., Effects of solvent medium on solubility. V: Enthalpic and entropic contributions to the free energy changes of Di-substituted benzene derivatives in ethanol: Water and ethanol: Cyclohexane mixtures, J. Pharm. Sci., 1990, 79, 12, 1109, https://doi.org/10.1002/jps.2600791214 . [all data]

El-Banna, 1978
El-Banna, H.M., Solid Dispersion of Pharmaceutaical Ternary Systems I. Phase Diagrams of Aspirin- Acetominophen-Urea Systems, J. Pharm. Sci., 1978, 67, 1109. [all data]

Vecchio and Tomassetti, 2009
Vecchio, Stefano; Tomassetti, Mauro, Vapor pressures and standard molar enthalpies, entropies and Gibbs energies of sublimation of three 4-substituted acetanilide derivatives, Fluid Phase Equilibria, 2009, 279, 1, 64-72, https://doi.org/10.1016/j.fluid.2009.02.001 . [all data]

Mota, Carneiro, et al., 2009
Mota, Fátima L.; Carneiro, Aristides P.; Queimada, António J.; Pinho, Simão P.; Macedo, Eugénia A., Temperature and solvent effects in the solubility of some pharmaceutical compounds: Measurements and modeling, European Journal of Pharmaceutical Sciences, 2009, 37, 3-4, 499-507, https://doi.org/10.1016/j.ejps.2009.04.009 . [all data]

Xu, Sun, et al., 2006
Xu, F.; Sun, L.X.; Tan, Z.C.; Liang, J.G.; Zhang, T., Adiabatic calorimetry and thermal analysis on acetaminophen, J Therm Anal Calorim, 2006, 83, 1, 187-191, https://doi.org/10.1007/s10973-005-6969-0 . [all data]

Romero, Bustamante, et al., 2004
Romero, S.; Bustamante, P.; Escalera, B.; Cirri, M.; Mura, P., Characterization of the solid phases of paracetamol and fenamates at equilibrium in saturated solutions, Journal of Thermal Analysis and Calorimetry, 2004, 77, 2, 541-554, https://doi.org/10.1023/B:JTAN.0000038993.61782.ba . [all data]

Manzo and Ahumada, 1990
Manzo, Ruben H.; Ahumada, Amelia A., Effects of solvent medium on solubility. V: Enthalpic and entropic contributions to the free energy changes of Di-substituted benzene derivatives in ethanol: Water and ethanol: Cyclohexane mixtures, J. Pharm. Sci., 1990, 79, 12, 1109-1115, https://doi.org/10.1002/jps.2600791214 . [all data]

Lang (editor), 1965
Lang (editor), L., Absorption Spectra in the Ultraviolet and Visible Region, 1965, 5, 93. [all data]

Notes

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• Symbols used in this document:
  

  Tfus	Fusion (melting) point
  ΔfusH	Enthalpy of fusion
  ΔsubH°	Enthalpy of sublimation at standard conditions
  ΔvapH	Enthalpy of vaporization

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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