Benzofuran

This article is about the heterocyclic chemical compound. For its purportedly recreational derivative drugs, see Benzofury (disambiguation).

Benzofuran is the heterocyclic compound consisting of fused benzene and furan rings. This colourless liquid is a component of coal tar. Benzofuran is the structural nucleus (parent compound) of many related compounds with more complex structures. For example, psoralen is a benzofuran derivative that occurs in several plants.

Benzofuran

Names
Preferred IUPAC name 1-Benzofuran[1]
Other names Benzofuran[1] Coumarone Benzo[b]furan
Identifiers
CAS Number	271-89-6 Y
3D model (JSmol)	Interactive image
Beilstein Reference	107704
ChEBI	CHEBI:35260 Y
ChEMBL	ChEMBL363614 Y
ChemSpider	8868 Y
DrugBank	DB04179 Y
ECHA InfoCard	100.005.439
EC Number	205-982-6
Gmelin Reference	260881
KEGG	C14512 Y
PubChem CID	9223
RTECS number	DF6423800
UNII	LK6946W774 Y
UN number	1993
CompTox Dashboard (EPA)	DTXSID6020141
InChI InChI=1S/C8H6O/c1-2-4-8-7(3-1)5-6-9-8/h1-6H Y Key: IANQTJSKSUMEQM-UHFFFAOYSA-N Y InChI=1/C8H6O/c1-2-4-8-7(3-1)5-6-9-8/h1-6H Key: IANQTJSKSUMEQM-UHFFFAOYAU
SMILES o2c1ccccc1cc2
Properties
Chemical formula	C8H6O
Molar mass	118.135 g·mol−1
Melting point	−18 °C (0 °F; 255 K)
Boiling point	173 °C (343 °F; 446 K)
Hazards
GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H226, H351, H412
Precautionary statements	P201, P202, P210, P233, P240, P241, P242, P243, P273, P280, P281, P303+P361+P353, P308+P313, P370+P378, P403+P235, P405, P501
Lethal dose or concentration (LD, LC):
LD50 (median dose)	500 mg/kg (mice).[2]
Related compounds
Related compounds	Benzothiophene, Indole, Indene, 2-Cumaranone
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

Production

Benzofuran is extracted from coal tar. It is also obtained by dehydrogenation of 2-ethylphenol.^[2]

Laboratory methods

Benzofurans can be prepared by various methods in the laboratory. Notable examples include:

• O-alkylation of salicylaldehyde with chloroacetic acid followed by dehydration (cyclication) of the resulting ether and decarboxylation.^[3]

• Perkin rearrangement, where a coumarin is reacted with a hydroxide:^[4][5][6]

• Diels–Alder reaction^{[clarification needed]} of nitro vinyl furans with various dienophiles:^[7]

• Cycloisomerization of alkyne ortho-substituted phenols:^[8]

Related compounds

• Substituted benzofurans
• Dibenzofuran, an analog with a second fused benzene ring.
• Furan, an analog without the fused benzene ring.
• Indole, an analog with a nitrogen instead of the oxygen atom.
• Benzothiophene, an analog with a sulfur instead of the oxygen atom.
• Isobenzofuran, the isomer with oxygen in the adjacent position.
• Aurone
• Thunberginol F