Indene
Template:Short description Page Template:Chembox/styles.css has no content.
Template:Chembox IndexlistTemplate:Chembox CompToxTemplate:Chembox OHS (set)Template:Chembox Datapage check| Lua error in package.lua at line 80: module 'Module:InfoboxImage/data' not found. | |
| Lua error in package.lua at line 80: module 'Module:InfoboxImage/data' not found. | |
| Names | |
|---|---|
| Preferred IUPAC name
1H-Indene[1] | |
| Other names
Benzocyclopentadiene
Indonaphthene Bicyclo[4.3.0]nona-1,3,5,7-tetraene | |
| Identifiers | |
| Page Template:Plainlist/styles.css has no content. | |
3D model (JSmol)
|
Page Template:Plainlist/styles.css has no content. |
| 635873 | |
| ChEBI | Page Template:Plainlist/styles.css has no content. |
| ChEMBL | Page Template:Plainlist/styles.css has no content. |
| ChemSpider | Page Template:Plainlist/styles.css has no content. |
| DrugBank | Page Template:Plainlist/styles.css has no content. |
| EC Number | Page Template:Plainlist/styles.css has no content. |
| 27265 | |
| KEGG | Page Template:Plainlist/styles.css has no content. |
PubChem CID
|
Page Template:Plainlist/styles.css has no content. |
| RTECS number | Page Template:Plainlist/styles.css has no content. |
| UNII | Page Template:Plainlist/styles.css has no content. |
| |
| Properties | |
| Page Module:Chem2/styles.css has no content.C9H8 | |
| Molar mass | 116.16 |
| Appearance | Colorless liquid[2] |
| Density | 0.997 g/mL |
| Melting point | −1.8 °C (28.8 °F; 271.3 K) |
| Boiling point | 181.6 °C (358.9 °F; 454.8 K) |
| Insoluble | |
| Acidity (pKa) | 20.1 (in DMSO)[3] |
| −80.89×10−6 cm3/mol | |
| Hazards | |
| Flash point | 78.3 °C (172.9 °F; 351.4 K) |
| NIOSH (US health exposure limits): | |
PEL (Permissible)
|
none[2] |
REL (Recommended)
|
TWA 10 ppm (45 mg/m3)[2] |
IDLH (Immediate danger)
|
N.D.[2] |
| Related compounds | |
Related compounds
|
Benzofuran, Benzothiophene, Indole |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
| |
Template:Chembox Footer/trackingTemplate:Short description
Indene is an aromatic, polycyclic hydrocarbon with chemical formula Page Module:Chem2/styles.css has no content.C9H8. It is composed of a benzene ring fused with a cyclopentene ring. This flammable liquid is colorless although samples often are pale yellow. The principal industrial use of indene is in the production of indene/coumarone thermoplastic resins. Substituted indenes and their closely related indane derivatives are important structural motifs found in many natural products and biologically active molecules, such as sulindac.[4]
Isolation
Indene occurs naturally in coal-tar fractions boiling around 175–185 °C. It can be obtained by heating this fraction with sodium to precipitate solid "sodio-indene". This step exploits indene's weak acidity evidenced by its deprotonation by sodium to give the indenyl derivative. The sodio-indene is converted back to indene by steam distillation.[5]
Reactivity
Indene readily polymerises. Oxidation of indene with acid dichromate yields homophthalic acid (o-carboxylphenylacetic acid). It condenses with diethyl oxalate in the presence of sodium ethoxide to form indene–oxalic ester, and with aldehydes or ketones in the presence of alkali to form benzofulvenes, which are highly coloured. Treatment of indene with organolithium reagents gives lithium indenyl compounds:
- Page Module:Chem2/styles.css has no content.C9H8 + RLi → LiC9H7 + RH
Indenyl is a ligand in organometallic chemistry, giving rise to many transition metal indenyl complexes.[6]
At temperatures ranging from 30-75 Kelvin (the temperature range of most dark molecular clouds and photodissociation regions), Indene undergoes a process called superhydrogenation. It begins with saturation of carbon atoms in the pentagonal ring which is then followed by the hydrogenation of the benzene unit. Quantum tunneling also plays a role is this.[7]
Applications
- Indene can also be used directly to synthesize 2-Aminoindan & NM-2-AI.[8]
- Indene is used as a starting material to make 2-indanone [615-13-4].[9] 2-indanone in-turn is used to synthesize the following drugs: Aprindine, Delapril, Indanorex, Indantadol, Pip-AI [23928-93-0], Pyr-AI, S-15535 & BChE-IN-7 [2416910-85-3], 2-aminoindane analog of fentanyl: O=C(CC)N(C1=CC=CC=C1)C2CCN(C3CC(C=CC=C4)=C4C3)CC2.
See also
References
- ^ Page Module:Citation/CS1/styles.css has no content.International Union of Pure and Applied Chemistry (2014). Nomenclature of Organic Chemistry: IUPAC Recommendations and Preferred Names 2013. The Royal Society of Chemistry. p. 207. doi:10.1039/9781849733069. ISBN 978-0-85404-182-4.
- ^ a b c d Page Module:Citation/CS1/styles.css has no content.NIOSH Pocket Guide to Chemical Hazards. "#0340". National Institute for Occupational Safety and Health (NIOSH).
- ^ Page Module:Citation/CS1/styles.css has no content.Bordwell FG (1988). "Equilibrium acidities in dimethyl sulfoxide solution". Accounts of Chemical Research. 21 (12): 456–463. doi:10.1021/ar00156a004. Bordwell pKa Table in DMSO Script error: No such module "webarchive".
- ^ Page Module:Citation/CS1/styles.css has no content.Wu, Jie; Qiu, Guanyinsheng (2014). "Generation of Indene Derivatives by Tandem Reactions". Synlett. 25 (19): 2703–2713. doi:10.1055/s-0034-1379318.
- ^ Script error: No such module "Template wrapper".
- ^ Page Module:Citation/CS1/styles.css has no content.O'Connor, Joseph M.; Casey, Charles P. (1987). "Ring-Slippage Chemistry of Transition Metal Cyclopentadienyl and Indenyl Complexes". Chemical Reviews. 87 (2): 307–318. doi:10.1021/cr00078a002.
- ^ Page Module:Citation/CS1/styles.css has no content.Haid, S.; Gugeler, K.; Kästner, J.; Campisi, D. (2025). "Superhydrogenation of indene at low temperatures". Astronomy & Astrophysics. 701: A34. arXiv:2507.22036. doi:10.1051/0004-6361/202451572.
- ^ Page Module:Citation/CS1/styles.css has no content.Yasuda, M., Kojima, R., Tsutsui, H., Utsunomiya, D., Ishii, K., Jinnouchi, K., Shiragami, T., Yamashita, T. (1 October 2003). "Redox-Photosensitized Aminations of 1,2-Benzo-1,3-cycloalkadienes, Arylcyclopropanes, and Quadricyclane with Ammonia". The Journal of Organic Chemistry. 68 (20): 7618–7624. doi:10.1021/jo030053+.
- ^ Page Module:Citation/CS1/styles.css has no content."2-INDANONE". Organic Syntheses. 41: 53. 1961. doi:10.15227/orgsyn.041.0053.
External links
- Page Module:Citation/CS1/styles.css has no content.W. v. Miller, Rohde (1890). "Zur Synthese von Indenderivaten". Berichte der Deutschen Chemischen Gesellschaft. 23 (2): 1881–1886. doi:10.1002/cber.18900230227.
- Page Module:Citation/CS1/styles.css has no content.W. v. Miller, Rohde (1890). "Zur Synthese von Indenderivaten". Berichte der Deutschen Chemischen Gesellschaft. 23 (2): 1887–1902. doi:10.1002/cber.18900230228.
- Page Module:Citation/CS1/styles.css has no content.Finar, I. L. (1985). Organic Chemistry. Longman Scientific & Technical. ISBN 0-582-44257-5.
Lua error in package.lua at line 80: module 'Module:Authority control/config' not found.
