gamma-Butyrolactone

Athanor · official

C₄H₆O₂ · 86.09 g/mol

IUPAC name: oxolan-2-one

Also called GBL, butyrolactone, dihydrofuran-2-one, oxolan-2-one

Rings Solvents

Open in Athanor

Drawn from its SMILES with RDKit

DangerHarmful if swallowed · Causes skin irritation · Causes serious eye damage · Causes serious eye irritation · Toxic if inhaled · May cause drowsiness or dizziness

Names and identifiers

IUPAC name: oxolan-2-one
Synonyms: GBL, butyrolactone, dihydrofuran-2-one
+ 38 more
oxolan-2-one, BUTYROLACTONE, dihydrofuran-2(3H)-one, 4-Butyrolactone, 4-Butanolide, 1,4-Butanolide, 4-Hydroxybutyric acid lactone, 2-Oxolanone, Dihydro-2(3H)-furanone, Butyryl lactone, Butyrylactone, 4-Deoxytetronic acid, 1,2-Butanolide, Butyric acid lactone, BLON, gamma-BL, 2(3H)-Furanone, dihydro-, Tetrahydro-2-furanone, 4-Hydroxybutanoic acid lactone, gamma-Hydroxybutyric acid lactone, Dihydro-2-furanone, 1,4-Lactone, Agrisynth BLO, gamma-6480, 2-Oxotetrahydrofuran, gamma-Hydroxybutyrolactone, No Go, gamma-Butalactone, 1-Oxacyclopentan-2-one, FEMA No. 3291, Paint Clean G, DTXSID6020224, gamma-Butyryllactone, gamma-Hydroxybutyric Acid cyclic ester, OL659KIY4X, 4 Hydroxybutyric Acid Lactone, 4,5-Dihydro-2(3H)-furanone, Butanoic acid, 4-hydroxy-, gamma-lactone
Molecular formula: C₄H₆O₂
Empirical formula: C₂H₃O
Molecular weight: 86.09 g/mol
Exact mass: 86.03678
CAS number: 96-48-0
PubChem CID: 7302
Canonical SMILES: C1CC(=O)OC1
Isomeric SMILES: C1CC(=O)OC1
InChI: InChI=1S/C4H6O2/c5-4-2-1-3-6-4/h1-3H2
InChIKey: YEJRWHAVMIAJKC-UHFFFAOYSA-N
Molfile

Names, InChI and the identifiers from PubChem, retrieved 2026-10-14.

Physical properties

TemperaturePressureDensity

Appearance: Colorless liquid[4]
4 values
From Hazardous Substances Data Bank (HSDB), the most authoritative source here.
Value As written Source
– 4-butyrolactone is a clear colorless oily liquid with a pleasant odor. (NTP, 1992) [1] CAMEO Chemicalscites National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
– Liquid [2] EPA Chemical Data Reporting (CDR)
– COLOURLESS OILY HYGROSCOPIC LIQUID. [3] ILO-WHO International Chemical Safety Cards (ICSCs)
–shown Colorless liquid [4] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 14th Edition. John Wiley & Sons, Inc. New York, NY 2001., p. 184
Odor: Faint odor[4]
2 values
From Hazardous Substances Data Bank (HSDB), the most authoritative source here.
Value As written Source
– Pleasant odor [4] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 14th Edition. John Wiley & Sons, Inc. New York, NY 2001., p. 184
–shown Faint odor [4] Hazardous Substances Data Bank (HSDB)cites Gerhartz, W. (exec ed.). Ullmann's Encyclopedia of Industrial Chemistry. 5th ed.Vol A1: Deerfield Beach, FL: VCH Publishers, 1985 to Present., p. VA4: 495
Melting point: -43.53 °C[4]
4 values
4 of 4 sources agree on it (most common value).
Value As written Source
−45 °C -49 °F (NTP, 1992) [1] CAMEO Chemicalscites National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
−43.5 °Cshown -43.53 °C [4] Hazardous Substances Data Bank (HSDB)cites Lide, D.R., G.W.A. Milne (eds.). Handbook of Data on Organic Compounds. Volume I. 3rd ed. CRC Press, Inc. Boca Raton ,FL. 1994., p. 2858
−44 °C -44 °C [3] ILO-WHO International Chemical Safety Cards (ICSCs)
−44 °C -44 °C [5] PAC Chemical Database, U.S. Department of Energy
Boiling point: 204 °C[3]
3 values
3 of 3 sources agree on it (most common value).
Value As written Source
204 to 205 °C 399 to 401 °F at 760 mmHg (NTP, 1992) [1] CAMEO Chemicalscites National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
204 °C 204 °C at 760 mm Hg [4] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 14th Edition. John Wiley & Sons, Inc. New York, NY 2001., p. 184
204 °Cshown 204 °C [3] ILO-WHO International Chemical Safety Cards (ICSCs)
Density: 1.1286 at 15 °C (59 °F) (NTP, 1992) - Denser than water[1]
3 values
2 of 3 sources agree on it (most common value).
Value As written Source
–shown 1.1286 at 59 °F (NTP, 1992) - Denser than water [1] CAMEO Chemicalscites National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
– Relative density (water = 1): 1.13 (20 °C) [3] ILO-WHO International Chemical Safety Cards (ICSCs)
– 1.41 @ 0°C [5] PAC Chemical Database, U.S. Department of Energy
Solubility in water: Solubility in water: very soluble[3]
4 values
From ILO-WHO International Chemical Safety Cards (ICSCs), the most authoritative source here.
Value As written Source
– greater than or equal to 100 mg/mL at 55 °F (NTP, 1992) [1] CAMEO Chemicalscites National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
– Miscible with alcohol and ether. [4] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 14th Edition. John Wiley & Sons, Inc. New York, NY 2001., p. 184
– Very soluble in acetone, benzene, diethyl ether, and ethanol. [4] Hazardous Substances Data Bank (HSDB)cites Lide, D.R., G.W.A. Milne (eds.). Handbook of Data on Organic Compounds. Volume I. 3rd ed. CRC Press, Inc. Boca Raton ,FL. 1994., p. 2858
–shown Solubility in water: very soluble [3] ILO-WHO International Chemical Safety Cards (ICSCs)
log P: -0.64[3]
2 values
2 of 2 sources agree on it (most common value).
Value As written Source
– log Kow = -0.64 [4] Hazardous Substances Data Bank (HSDB)cites Hansch, C., Leo, A., D. Hoekman. Exploring QSAR - Hydrophobic, Electronic, and Steric Constants. Washington, DC: American Chemical Society., 1995., p. 9
–shown -0.64 [3] ILO-WHO International Chemical Safety Cards (ICSCs)
Vapor pressure: Vapor pressure, kPa at 20 °C: 0.15[3]
2 values
Only one source reports it.
Value As written Source
< 1 mmHg less than 1 mmHg at 77 °F (NTP, 1992) [1] CAMEO Chemicalscites National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
1.1 mmHgshown Vapor pressure, kPa at 20 °C: 0.15 [3] ILO-WHO International Chemical Safety Cards (ICSCs)
Flash point: 98 °C (209 °F) (open cup)[4]
3 values
3 of 3 sources agree on it (most common value).
Value As written Source
98 °C 209 °F (NTP, 1992) [1] CAMEO Chemicalscites National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
98 °Cshown 209 °F (98 °C) (open cup) [4] Hazardous Substances Data Bank (HSDB)cites Fire Protection Guide to Hazardous Materials. 13 ed. Quincy, MA: National Fire Protection Association, 2002., p. 325-28
98 °C 98 °C c.c. [3] ILO-WHO International Chemical Safety Cards (ICSCs)
Autoignition temperature: 455 °C[3]
2 values
2 of 2 sources agree on it (most common value).
Value As written Source
455 °C 455 °C [4] Hazardous Substances Data Bank (HSDB)cites International Program on Chemical Safety/Commission of the European Communities; International Chemical Safety Card on gamma-Butyrolactone (October 2000). Available from, as of January 14, 2008: https://www.inchem.org/pages/icsc.html
455 °Cshown 455 °C [3] ILO-WHO International Chemical Safety Cards (ICSCs)
Viscosity: 1.75 centipoise at 25 °C[4]

Value	As written	Source
–	4-butyrolactone is a clear colorless oily liquid with a pleasant odor. (NTP, 1992)	[1] CAMEO Chemicalscites National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
–	Liquid	[2] EPA Chemical Data Reporting (CDR)
–	COLOURLESS OILY HYGROSCOPIC LIQUID.	[3] ILO-WHO International Chemical Safety Cards (ICSCs)
–shown	Colorless liquid	[4] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 14th Edition. John Wiley & Sons, Inc. New York, NY 2001., p. 184

Value	As written	Source
–	Pleasant odor	[4] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 14th Edition. John Wiley & Sons, Inc. New York, NY 2001., p. 184
–shown	Faint odor	[4] Hazardous Substances Data Bank (HSDB)cites Gerhartz, W. (exec ed.). Ullmann's Encyclopedia of Industrial Chemistry. 5th ed.Vol A1: Deerfield Beach, FL: VCH Publishers, 1985 to Present., p. VA4: 495

Value	As written	Source
−45 °C	-49 °F (NTP, 1992)	[1] CAMEO Chemicalscites National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
−43.5 °Cshown	-43.53 °C	[4] Hazardous Substances Data Bank (HSDB)cites Lide, D.R., G.W.A. Milne (eds.). Handbook of Data on Organic Compounds. Volume I. 3rd ed. CRC Press, Inc. Boca Raton ,FL. 1994., p. 2858
−44 °C	-44 °C	[3] ILO-WHO International Chemical Safety Cards (ICSCs)
−44 °C	-44 °C	[5] PAC Chemical Database, U.S. Department of Energy

Value	As written	Source
204 to 205 °C	399 to 401 °F at 760 mmHg (NTP, 1992)	[1] CAMEO Chemicalscites National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
204 °C	204 °C at 760 mm Hg	[4] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 14th Edition. John Wiley & Sons, Inc. New York, NY 2001., p. 184
204 °Cshown	204 °C	[3] ILO-WHO International Chemical Safety Cards (ICSCs)

Value	As written	Source
–shown	1.1286 at 59 °F (NTP, 1992) - Denser than water	[1] CAMEO Chemicalscites National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
–	Relative density (water = 1): 1.13 (20 °C)	[3] ILO-WHO International Chemical Safety Cards (ICSCs)
–	1.41 @ 0°C	[5] PAC Chemical Database, U.S. Department of Energy

Value	As written	Source
–	greater than or equal to 100 mg/mL at 55 °F (NTP, 1992)	[1] CAMEO Chemicalscites National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
–	Miscible with alcohol and ether.	[4] Hazardous Substances Data Bank (HSDB)cites Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 14th Edition. John Wiley & Sons, Inc. New York, NY 2001., p. 184
–	Very soluble in acetone, benzene, diethyl ether, and ethanol.	[4] Hazardous Substances Data Bank (HSDB)cites Lide, D.R., G.W.A. Milne (eds.). Handbook of Data on Organic Compounds. Volume I. 3rd ed. CRC Press, Inc. Boca Raton ,FL. 1994., p. 2858
–shown	Solubility in water: very soluble	[3] ILO-WHO International Chemical Safety Cards (ICSCs)

Value	As written	Source
–	log Kow = -0.64	[4] Hazardous Substances Data Bank (HSDB)cites Hansch, C., Leo, A., D. Hoekman. Exploring QSAR - Hydrophobic, Electronic, and Steric Constants. Washington, DC: American Chemical Society., 1995., p. 9
–shown	-0.64	[3] ILO-WHO International Chemical Safety Cards (ICSCs)

Value	As written	Source
< 1 mmHg	less than 1 mmHg at 77 °F (NTP, 1992)	[1] CAMEO Chemicalscites National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
1.1 mmHgshown	Vapor pressure, kPa at 20 °C: 0.15	[3] ILO-WHO International Chemical Safety Cards (ICSCs)

Value	As written	Source
98 °C	209 °F (NTP, 1992)	[1] CAMEO Chemicalscites National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
98 °Cshown	209 °F (98 °C) (open cup)	[4] Hazardous Substances Data Bank (HSDB)cites Fire Protection Guide to Hazardous Materials. 13 ed. Quincy, MA: National Fire Protection Association, 2002., p. 325-28
98 °C	98 °C c.c.	[3] ILO-WHO International Chemical Safety Cards (ICSCs)

Value	As written	Source
455 °C	455 °C	[4] Hazardous Substances Data Bank (HSDB)cites International Program on Chemical Safety/Commission of the European Communities; International Chemical Safety Card on gamma-Butyrolactone (October 2000). Available from, as of January 14, 2008: https://www.inchem.org/pages/icsc.html
455 °Cshown	455 °C	[3] ILO-WHO International Chemical Safety Cards (ICSCs)

Each value as its source reports it, with the source's number after it (listed under References). Where several sources report a property, the row shows the value most of them agree on, the rule the app uses; open the values to see every one.

Calculated

Heavy atoms: 6
Rings: 1
Aromatic rings: 0
Fraction sp³ carbons (Fsp3): 0.75
H-bond donors: 0
H-bond acceptors: 2
Rotatable bonds: 0
TPSA (Å²): 26.3
Formal charge: 0
XLogP3: -0.6 PubChem
Complexity: 67 PubChem
Stereocenters: None
Double-bond geometry: None specified
Point group: C1 of one 3D conformer with its hydrogens, by Athanor’s engine (as in the app)

Elemental analysis

C55.81%
H7.03%
O37.17%

Isotope pattern

Each peak is a nominal mass with its abundance-weighted exact mass, as a percentage of the tallest, from IUPAC natural isotope abundances.

Computed from the structure with RDKit 2026.09 when this page was built, beside PubChem's own computed values from its record; where the two differ, both are shown.

Predicted

log P: 0.32 Crippen (Wildman and Crippen 1999)
log S (water solubility): -0.58 ESOL (Delaney 2004), log mol/L
Synthetic accessibility: 2.47 SA score, 1 easy to 10 hard (Ertl and Schuffenhauer 2009)

Drug-likeness: Lipinski’s rule of five

Molecular weight ≤ 500: 86.09
log P ≤ 5 (Crippen): 0.32
H-bond donors ≤ 5: 0
H-bond acceptors ≤ 10: 2

Passes all four rules.

¹³C NMR shifts, predicted

Predictions, not measurements; each names its method. A measured log P, where a source reports one, is under Physical properties.

Safety

Danger

Most widely reported: 3,692 company reports to ECHA. Source [6].

Corrosive
Acute toxicity
Harmful or irritant

NFPA 704[4]

H302Harmful if swallowed (99.6% of reports)
H315Causes skin irritation (12.4% of reports)
H318Causes serious eye damage (68.3% of reports)
H319Causes serious eye irritation (31.5% of reports)
H331Toxic if inhaled (12.2% of reports)
H336May cause drowsiness or dizziness (62% of reports)

Precautionary statements: P261, P264, P264+P265, P270, P271, P280, P301+P317, P302+P352, P304+P340, P305+P351+P338, P305+P354+P338, P316, P317, P319, P321, P330, P332+P317, P337+P317, P362+P364, P403+P233, P405, P501

View all classifications (2)

[6] European Chemicals Agency (ECHA)This chemical does not meet GHS hazard criteria for 0.4% (16 of 3692) of reports.
[6] European Chemicals Agency (ECHA) · 3,692 reports · DangerH302, H315, H318, H319, H331, H336

First aid

Eyes: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. Immediately transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop. Skin: Immediately flood affected skin with water while removing and isolating all contaminated clothing.[1]
Fresh air, rest. Seek medical attention if you feel unwell.[3]
Wear protective gloves when administering first aid. Rinse skin with plenty of water or shower.[3]
Rinse with plenty of water for several minutes (remove contact lenses if easily possible). Refer immediately for medical attention.[3]

Storage

Store only in original container. Separated from acids, alcohols, amines, bases and oxidants. Dry. Well closed. Store in an area without drain or sewer access.[3]
Butyrolactone can be stored indefinitely. The pure product is noncorrosive and therefore can be stored and transported in carbon steel containers. Butyrolactone becomes slightly yellow on prolonged storage in carbon steel vessels without nitrogen padding. In this case stainless steel containers are recommended. The hygroscopicity of the product requires some precautions. Butyrolactone attacks concrete vigorously.[4]
Separated from acids, alcohols, amines and bases. Dry.[4]

Incompatibilities

... Can react with oxidizing materials.[4]
Potentially explosive reaction with butanol + 2,4-dichlorophenol + sodium hydroxide.[4]
Reacts with inorganic acids and bases, alcohols and amines.[4]

Always read the supplier’s safety data sheet before working with it.

Spectra

Experimental spectra held by these sources; each link opens the source's own record.

Literature

Reading PubChem, OpenAlex and GSRS…

Bioactivity

Reading ChEMBL…

References

[1]CAMEO Chemicals · Public domain (NOAA) · via PubChem · retrieved 2026-10-14
[2]EPA Chemical Data Reporting (CDR) · Public domain (US EPA) · via PubChem · retrieved 2026-10-14
[3]ILO-WHO International Chemical Safety Cards (ICSCs) · CC BY 4.0 · via PubChem · retrieved 2026-10-14
[4]Hazardous Substances Data Bank (HSDB) · Public domain (US NLM) · via PubChem · retrieved 2026-10-14
[5]PAC Chemical Database, U.S. Department of Energy · Public domain (US DOE) · via PubChem · retrieved 2026-10-14
[6]European Chemicals Agency (ECHA) · ECHA legal notice: reuse with acknowledgement · via PubChem · retrieved 2026-10-14
[7]NMRShiftDB · Linked only · via PubChem · retrieved 2026-10-14
[8]Human Metabolome Database (HMDB) · Linked only · via PubChem · retrieved 2026-10-14
[9]SpectraBase · Linked only · via PubChem · retrieved 2026-10-14
[10]MassBank of North America (MoNA) · CC BY 4.0 · via PubChem · retrieved 2026-10-14
[11]NIST Mass Spectrometry Data Center · Linked only · via PubChem · retrieved 2026-10-14
[12]MassBank Europe · Linked only · via PubChem · retrieved 2026-10-14
·Calculated values: computed by Athanor with RDKit 2026.09 from the structure.
·Literature on PubChem

Data last updated 2026-10-14.