Acetaminophen
- Formula: C8H9NO2
- Molecular weight: 151.1626
- IUPAC Standard InChIKey: RZVAJINKPMORJF-UHFFFAOYSA-N
- 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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Phase change data
Go To: Top, Gas phase ion energetics data, IR Spectrum, THz IR spectrum, References, Notes
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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tfus | 441.2 | K | N/A | Manzo and Ahumanda, 1990 | Uncertainty assigned by TRC = 0.5 K; TRC |
Tfus | 441. | K | N/A | El-Banna, 1978 | Uncertainty assigned by TRC = 2. K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔsubH° | 138. ± 3. | kJ/mol | Fus+Vap | Vecchio and Tomassetti, 2009 | AC |
Enthalpy of vaporization
ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
103. ± 3. | 521. | TGA | Vecchio and Tomassetti, 2009 | AC |
99. ± 1. | 494. | TGA | Vecchio and Tomassetti, 2009 | AC |
Enthalpy of fusion
ΔfusH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
27.6 | 443.2 | DSC | Mota, Carneiro, et al., 2009 | AC |
27.0 | 440.3 | DSC | Vecchio and Tomassetti, 2009 | AC |
26.49 | 441.9 | AC,DSC | Xu, Sun, et al., 2006 | AC |
26.2 | 443. | DSC | Romero, Bustamante, et al., 2004 | AC |
26.02 | 441.2 | N/A | Manzo and Ahumada, 1990 | AC |
Gas phase ion energetics data
Go To: Top, Phase change data, IR Spectrum, THz IR spectrum, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled by: Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
Ionization energy determinations
IE (eV) | Method | Reference |
---|---|---|
7.57 ± 0.02 | EI | Benezra and Bursey, 1972 |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C6H6NO+ | 13.52 ± 0.02 | CH3CO | EI | Benezra and Bursey, 1972 | |
C6H7NO+ | 9.82 ± 0.02 | CH2=C=O | EI | Benezra and Bursey, 1972 |
IR Spectrum
Go To: Top, Phase change data, Gas phase ion energetics data, THz IR spectrum, References, Notes
Data compiled by: Coblentz Society, Inc.
Data compiled by: Timothy J. Johnson, Tanya L. Myers, Yin-Fong Su, Russell G. Tonkyn, Molly Rose K. Kelly-Gorham, and Tyler O. Danby
Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director
THz IR spectrum
Go To: Top, Phase change data, Gas phase ion energetics data, IR Spectrum, References, Notes
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
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Owner | Collection (C) 2005 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
State | Solid (powder) |
Sample description | 8.1 mg + 113.5 mg polyethylene spectrograde powder |
Sample contents | acetaminophen |
References
Go To: Top, Phase change data, Gas phase ion energetics data, IR Spectrum, THz IR 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]
Benezra and Bursey, 1972
Benezra, S.A.; Bursey, M.M.,
Hydrogen bonding in mass spectral activated complexes. A correction,
J. Chem. Soc. Perkin Trans. 2, 1972, 11, 1537. [all data]
Notes
Go To: Top, Phase change data, Gas phase ion energetics data, IR Spectrum, THz IR spectrum, References
- Symbols used in this document:
AE Appearance energy 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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