Pinacolone (3,3-dimethyl-2-butanone) is an important ketone in organic chemistry. It is a colorless liquid with a slight peppermint or camphor odor. It is a precursor to triazolylpinacolone in the synthesis of the fungicide triadimefon and in synthesis of the herbicide metribuzin. The molecule is an unsymmetrical ketone. The α-methyl group can participate in condensation reactions. The carbonyl group can undergo the usual reactions (hydrogenation, reductive amination, etc.). It is a Schedule 3 compound under the Chemical Weapons Convention 1993, due to being related to pinacolyl alcohol, which is used in the production of soman.[2] It is also a controlled export in Australia Group member states.[3]
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| Names | |||
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| Preferred IUPAC name
3,3-Dimethylbutan-2-one | |||
| Other names
t-Butyl methyl ketone
1,1,1-Trimethylacetone | |||
| Identifiers | |||
3D model (JSmol)
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| 1209331 | |||
| ChEBI | |||
| ChemSpider | |||
| ECHA InfoCard | 100.000.838 | ||
| EC Number |
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| MeSH | Pinacolone | ||
PubChem CID
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| RTECS number |
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| UNII | |||
| UN number | 1224 | ||
CompTox Dashboard (EPA)
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| Properties | |||
| C6H12O | |||
| Molar mass | 100.161 g·mol−1 | ||
| Appearance | Colorless liquid | ||
| Density | 0.801 g cm−3 | ||
| Melting point | −52[1] °C (−62 °F; 221 K) | ||
| Boiling point | 103 to 106 °C (217 to 223 °F; 376 to 379 K) | ||
| -69.86·10−6 cm3/mol | |||
| Hazards | |||
| GHS labelling: | |||
 
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| Danger | |||
| H225, H302, H315, H319, H332, H335, H412 | |||
| P210, P233, P240, P241, P242, P243, P261, P264, P270, P271, P273, P280, P301+P312, P302+P352, P303+P361+P353, P304+P312, P304+P340, P305+P351+P338, P312, P321, P330, P332+P313, P337+P313, P362, P370+P378, P403+P233, P403+P235, P405, P501 | |||
| NFPA 704 (fire diamond) | |||
| Flash point | 5 °C (41 °F; 278 K) | ||
| Safety data sheet (SDS) | External MSDS | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Preparation
editMost famously, at least in the classroom, pinacolone arises by the pinacol rearrangement, which occurs by protonation of pinacol (2,3-dimethylbutane-2,3-diol).[4]
Industrially pinacolone is made by the hydrolysis of 4,4,5-trimethyl-1,3-dioxane, which is the product of isoprene and formaldehyde via the Prins reaction. It also is generated by ketonization of pivalic acid and acetic acid or acetone over metal oxide catalysts. 3-Methylbutanal is a starting material for 2,3-dimethyl-2-butene, which in turn is converted to pinacolone. Pinacolone can also be produced from 2-methy-2-butanol when reacted with C5 alcohols.[5]
Uses
editPinacolone is produced in large amounts for use in fungicides, herbicides, and pesticides. Some derivatives include:
- retrosynthetic analysis of vibunazole showed that it was derived from pinacolone.
- It is also used to prepare pinacidil, as well as naminidil.
- Stiripentol
- Tribuzone
- Pivaloylacetonitrile is used in the synthesis of Doramapimod.
- Triadimefon
- Diclobutrazole
- Paclobutrazol
- Valconazole
- Diethylstilbestrol pinacolone [18922-13-9].[6]
- Some kind of Bisphenol A derivative also U.S. patent 4,599,463
- Thiofanox
See also
editReferences
edit- ^ "Pinacolone | C6H12O | ChemSpider".
- ^ Handbook of chemical and biological warfare agents (2nd ed.). CRC Press. 24 August 2007. ISBN 9780849314346.
- ^ "Export Control List: Chemical Weapons Precursors". Australia Group. australiagroup.net. Retrieved 7 April 2017.
- ^ G. A. Hill and E. W. Flosdorf (1941). "Pinacolone". Organic Syntheses; Collected Volumes, vol. 1, p. 462.
- ^ Siegel, H; Eggersdorfer (2012). Ketones. 5. Vol. 20. doi:10.1002/14356007.a15_077. ISBN 9783527306732.
{{cite book}}:|journal=ignored (help) - ^ Oda, T; Sato, Y; Kodama, M; Kaneko, M (July 1993). "Inhibition of DNA topoisomerase I activity by diethylstilbestrol and its analogues". Biological & Pharmaceutical Bulletin. 16 (7): 708–10. doi:10.1248/bpb.16.708. PMID 8401407.