| Isoprenol |
 |
| IUPAC name | |
| Other names | 3-Methyl-3-buten-1-ol |
| Identifiers |
| CAS number | 763-32-6  Y |
| EC-number | 212-110-8 |
| InChI | 1/C5H10O/c1-5(2)3-4-6/h6H,1,3-4H2,2H3 |
| ChemSpider ID | 12448 |
| Properties[1] |
| Molecular formula | C5H10O |
| Molar mass | 86.132 g/mol |
| Density | 0.853 g/cm3 |
| Boiling point | 130–132 ºC |
| Refractive index (nD) | 1.433 |
| Hazards[2] |
| EU Index | not listed |
| GHS pictograms |   |
| GHS signal word | WARNING |
| GHS hazard statements | H226, H319 |
| GHS precautionary statements | P210, P233, P240, P241, P242, P243, P264, P280, P303+361+353, P305+351+338, P337+313, P370+378, P403+235, P501 |
| Flash point | 36 ºC (97 ºF)[note 1] |
| Related compounds |
| Related compounds | Prenol |
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) |
| Infobox references |
Isoprenol, also known as 3-methylbut-3-en-1-ol, is a hemiterpene alcohol. It is produced industrially as an intermediate to 3-methylbut-2-en-1-ol (prenol): global production in 2001 can be estimated as 6–13 thousand tons.[3]
Isoprenol is produced by the reaction between isobutene (2-methylpropene) and formaldehyde.
The thermodynamically preferred isomer with the more substituted double bond cannot be directly formed in this reaction, but isomerization yields the desired product:
The reaction is catalyzed by any species which can form an allyl complex without excessive hydrogenation of the substrate, for example poisoned palladium catalysts.[4]
- ^ Sigma-Aldrich Co. gives a value for the flash point of isoprenol of 42 ºC (108 ºF). The difference in the two values does not alter the safety classification of isoprenol as a category 3 flammable liquid under the GHS; but the lower value quoted here (from the New Zealand Environmental Risk Management Authority) would make it a class IC flammable liquid instead of a class II combustible liquid under the U.S. OSHA classification (29 C.F.R § 1910.106), and F3 rather than F2 under the NFPA 704 standard.
[edit] References
- ^ Source: Sigma-Aldrich Co., product no. W519308 (data accessed 2009-08-31).
- ^ HSNO Chemical Classification Information Database (New Zealand Environmental Risk Management Authority), http://www.ermanz.govt.nz/Chemicals/ChemicalDisplay.aspx?SubstanceID=13375, retrieved 2009-08-31 .
- ^ 3-Methyl-2-buten-1-ol, SIDS Initial Assessment Report, Geneva: United Nations Environment Programme, May 2005, http://www.inchem.org/documents/sids/sids/556821.pdf .
- ^ See, eg, Kogan, S. B.; Kaliya, M.; Froumin, N. (2006), "Liquid phase isomerization of isoprenol into prenol in hydrogen environment", Appl. Catal. A: Gen. 297 (2): 231–36, doi:10.1016/j.apcata.2005.09.010 .
