Carbazole (C12H9N): structure, properties and hazards

Names and identifiers

IUPAC name: 9H-carbazole
Synonyms: dibenzopyrrole, 9-azafluorene, 9H-Carbazole
+ 37 more
Dibenzopyrrole, Diphenylenimine, 9-Azafluorene, Diphenylenimide, Diphenyleneimine, Dibenzo[b,d]pyrrole, USAF EK-600, Dibenzo(b,d)pyrrole, DTXSID4020248, SKF 20091, 0P2197HHHN, NSC-3498, DTXCID40248, CHEBI:27543, RefChem:574162, CHEBI:3391, CHEBI:39205, 201-696-0, NSC 3498, MFCD00004960, Carvedilol Carbazole Impurity, diphenyleneimide, CAS-86-74-8, SMR000112232, CCRIS 121, HSDB 2164, EINECS 201-696-0, UNII-0P2197HHHN, para-carbazole, AI3-00096, 9H carbazole, 9-H-carbazole, 9CA, Carbazole, 96%, Chlorophenesin carbamate, CARBAZOLE [MI], Carbazole (High Purity)
Molecular formula: C₁₂H₉N
Empirical formula: C₁₂H₉N
Molecular weight: 167.21 g/mol
Exact mass: 167.07350
CAS number: 86-74-8
PubChem CID: 6854
Canonical SMILES: C1=CC=C2C(=C1)C3=CC=CC=C3N2
Isomeric SMILES: C1=CC=C2C(=C1)C3=CC=CC=C3N2
InChI: InChI=1S/C12H9N/c1-3-7-11-9(5-1)10-6-2-4-8-12(10)13-11/h1-8,13H
InChIKey: UJOBWOGCFQCDNV-UHFFFAOYSA-N
Molfile

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

Physical properties

TemperaturePressureDensity

Appearance: White crystals[2]
3 values
From Hazardous Substances Data Bank (HSDB), the most authoritative source here.
Value As written Source
– Carbazole appears as white crystals, plates, leaflets or light tan powder. Sublimes readily. Exhibits strong fluorescence and long phosphorescence on exposure to ultraviolet light. (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.
–shown White crystals [2] Hazardous Substances Data Bank (HSDB)cites Larranaga, M.D., Lewis, R.J. Sr., Lewis, R.A.; Hawley's Condensed Chemical Dictionary 16th Edition. John Wiley & Sons, Inc. Hoboken, NJ 2016., p. 256
– White crystals, plates, leaflets or light tan powder [2] Hazardous Substances Data Bank (HSDB)cites NOAA; CAMEO Chemicals. Database of Hazardous Materials. Carbazole (86-74-8). Natl Ocean Atmos Admin, Off Resp Rest; NOAA Ocean Serv. Available from, as of Mar 15, 2017: https://cameochemicals.noaa.gov/
Odor: Characteristic odor[2]
Melting point: 244.8 °C[3]
2 values
2 of 2 sources agree on it (most common value).
Value As written Source
245 to 246 °C 473 to 475 °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.
244.8 °Cshown 244.8 °C [3] PAC Chemical Database, U.S. Department of Energy
Boiling point: 354.7 °C @760 [mmHg][3]
2 values
2 of 2 sources agree on it (most common value).
Value As written Source
355 °C 671 °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.
354.7 °Cshown 354.7 °C @760 [mm Hg] [3] PAC Chemical Database, U.S. Department of Energy
Density: 1.10 @18°C[3]
2 values
2 of 2 sources agree on it (most common value).
Value As written Source
– 1.1 at 64 °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.
–shown 1.10 @18°C [3] PAC Chemical Database, U.S. Department of Energy
Solubility in water: In water, 1.80 mg/L at 25 °C[2]
3 values
From Hazardous Substances Data Bank (HSDB), the most authoritative source here.
Value As written Source
– less than 1 mg/mL at 66 °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.
–shown In water, 1.80 mg/L at 25 °C [2] Hazardous Substances Data Bank (HSDB)cites Ainsworth CC et al; Soil Sci Soc Amer J 53: 1391-1401 (1989)
– In water, 1.20 mg/L at 20 °C [2] Hazardous Substances Data Bank (HSDB)cites Yalkowsky, S.H., He, Yan, Jain, P. Handbook of Aqueous Solubility Data Second Edition. CRC Press, Boca Raton, FL 2010
log P: log Kow = 3.72[2]
pKa: pKa = -6.0[2]
Vapor pressure: 400 [mmHg] @323 °C[3]
3 values
2 of 3 sources agree on it (most common value).
Value As written Source
400 mmHg 400 mmHg at 613 °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.
0.0000015 mmHg 1.5X10-6 mm Hg at 25 °C (extrapolated) [2] Hazardous Substances Data Bank (HSDB)cites Jimenez P et al; J Chem Thermodyn 22: 721-726 (1990)
400 mmHgshown 400 [mm Hg] @323 °C [3] PAC Chemical Database, U.S. Department of Energy
Flash point: 220.0 °C (428.0 °F) - closed cup[2]

Value	As written	Source
–	Carbazole appears as white crystals, plates, leaflets or light tan powder. Sublimes readily. Exhibits strong fluorescence and long phosphorescence on exposure to ultraviolet light. (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.
–shown	White crystals	[2] Hazardous Substances Data Bank (HSDB)cites Larranaga, M.D., Lewis, R.J. Sr., Lewis, R.A.; Hawley's Condensed Chemical Dictionary 16th Edition. John Wiley & Sons, Inc. Hoboken, NJ 2016., p. 256
–	White crystals, plates, leaflets or light tan powder	[2] Hazardous Substances Data Bank (HSDB)cites NOAA; CAMEO Chemicals. Database of Hazardous Materials. Carbazole (86-74-8). Natl Ocean Atmos Admin, Off Resp Rest; NOAA Ocean Serv. Available from, as of Mar 15, 2017: https://cameochemicals.noaa.gov/

Value	As written	Source
245 to 246 °C	473 to 475 °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.
244.8 °Cshown	244.8 °C	[3] PAC Chemical Database, U.S. Department of Energy

Value	As written	Source
355 °C	671 °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.
354.7 °Cshown	354.7 °C @760 [mm Hg]	[3] PAC Chemical Database, U.S. Department of Energy

Value	As written	Source
–	1.1 at 64 °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.
–shown	1.10 @18°C	[3] PAC Chemical Database, U.S. Department of Energy

Value	As written	Source
–	less than 1 mg/mL at 66 °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.
–shown	In water, 1.80 mg/L at 25 °C	[2] Hazardous Substances Data Bank (HSDB)cites Ainsworth CC et al; Soil Sci Soc Amer J 53: 1391-1401 (1989)
–	In water, 1.20 mg/L at 20 °C	[2] Hazardous Substances Data Bank (HSDB)cites Yalkowsky, S.H., He, Yan, Jain, P. Handbook of Aqueous Solubility Data Second Edition. CRC Press, Boca Raton, FL 2010

Value	As written	Source
400 mmHg	400 mmHg at 613 °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.
0.0000015 mmHg	1.5X10-6 mm Hg at 25 °C (extrapolated)	[2] Hazardous Substances Data Bank (HSDB)cites Jimenez P et al; J Chem Thermodyn 22: 721-726 (1990)
400 mmHgshown	400 [mm Hg] @323 °C	[3] PAC Chemical Database, U.S. Department of Energy

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: 13
Rings: 3
Aromatic rings: 3
Fraction sp³ carbons (Fsp3): 0
H-bond donors: 1
H-bond acceptors: 0
Rotatable bonds: 0
TPSA (Å²): 15.8
Formal charge: 0
XLogP3: 3.7 PubChem
Complexity: 170 PubChem
Stereocenters: None
Double-bond geometry: None specified
Point group: C2v of one 3D conformer with its hydrogens, by Athanor’s engine (as in the app)

Elemental analysis

C86.20%
H5.43%
N8.38%

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: 3.32 Crippen (Wildman and Crippen 1999)
log S (water solubility): -3.71 ESOL (Delaney 2004), log mol/L
Synthetic accessibility: 1.47 SA score, 1 easy to 10 hard (Ertl and Schuffenhauer 2009)

Drug-likeness: Lipinski’s rule of five

Molecular weight ≤ 500: 167.21
log P ≤ 5 (Crippen): 3.32
H-bond donors ≤ 5: 1
H-bond acceptors ≤ 10: 0

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

Warning

Most widely reported: 229 company reports to ECHA. Source [4].

Harmful or irritant
Health hazard
Environmental hazard

H315Causes skin irritation (10% of reports)
H341Suspected of causing genetic defects (52.8% of reports)
H351Suspected of causing cancer (70.3% of reports)
H400Very toxic to aquatic life (16.2% of reports)
H411Toxic to aquatic life with long lasting effects (48% of reports)
H413May cause long lasting harmful effects to aquatic life (23.1% of reports)

Precautionary statements: P203, P264, P273, P280, P302+P352, P318, P321, P332+P317, P362+P364, P391, P405, P501

View all classifications (3)

[4] European Chemicals Agency (ECHA)This chemical does not meet GHS hazard criteria for 10.9% (25 of 229) of reports.
[4] European Chemicals Agency (ECHA) · 229 reports · WarningH315, H341, H351, H400, H411, H413
[2] Hazardous Substances Data Bank (HSDB) · WarningH351, H413

Exposure limits

TLV: For more Threshold Limit Values (TLV) (Complete) data for Carbazole (6 total), please visit the HSDB record page.[2]
IDLH: NIOSH considers coal tar pitch volatiles to be potential occupational carcinogens. (coal tar pitch volatiles)[2]

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]

Storage

Keep container tightly closed in a dry and well-ventilated place.[2]

Incompatibilities

Incompatible materials: Oxidizing agents.[2]
Strong oxidizers.[2]

Safety data sheets on the supplier’s page: AKos Consulting & Solutions, Achemtek, Biorbyt.

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]Hazardous Substances Data Bank (HSDB) · Public domain (US NLM) · via PubChem · retrieved 2026-10-14
[3]PAC Chemical Database, U.S. Department of Energy · Public domain (US DOE) · via PubChem · retrieved 2026-10-14
[4]European Chemicals Agency (ECHA) · ECHA legal notice: reuse with acknowledgement · via PubChem · retrieved 2026-10-14
[5]NMRShiftDB · Linked only · via PubChem · retrieved 2026-10-14
[6]SpectraBase · Linked only · via PubChem · retrieved 2026-10-14
[7]Human Metabolome Database (HMDB) · Linked only · via PubChem · retrieved 2026-10-14
[8]MassBank of North America (MoNA) · CC BY 4.0 · via PubChem · retrieved 2026-10-14
[9]NIST Mass Spectrometry Data Center · Linked only · via PubChem · retrieved 2026-10-14
[10]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.