Cycloheptanone
{{Chembox
| Watchedfields = changed
| verifiedrevid = 460110237
| ImageFile = Cycloheptanone.svg
| ImageSize = 100px
| PIN = Cycloheptanone
| OtherNames = Suberone
|Section1={{Chembox Identifiers
| CASNo = 502-42-1
| CASNo_Ref = {{cascite|correct|CAS}}
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = QH80295937
| ChEMBL_Ref = {{ebicite|correct|EBI}}
| ChEMBL = 18607
| PubChem = 10400
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 9971
| EINECS = 207-937-6
| SMILES = O=C1CCCCCC1
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/C7H12O/c8-7-5-3-1-2-4-6-7/h1-6H2
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = CGZZMOTZOONQIA-UHFFFAOYSA-N
}}
|Section2={{Chembox Properties
| C=7 | H=12 | O=1
| Appearance = Colorless liquid
| Density = 0.949 g/cm3 (20 °C)The Merck Index, 11th Edition, 2728
| MeltingPt =
| BoilingPtC = 179 to 181
| Solubility = Insoluble
}}
|Section3={{Chembox Hazards
| MainHazards =
| FlashPtC = 56
| FlashPt_ref = [http://www.sigmaaldrich.com/catalog/ProductDetail.do?lang=en&N4=C99000|ALDRICH&N5=SEARCH_CONCAT_PNO|BRAND_KEY&F=SPEC Cycloheptanone] at Sigma-Aldrich
| AutoignitionPt =
| GHSPictograms = {{GHS02}}{{GHS05}}{{GHS07}}
| GHSSignalWord = Danger
| HPhrases = {{H-phrases|226|302|318}}
| PPhrases = {{P-phrases|210|233|240|241|242|243|264|270|280|301+312|303+361+353|305+351+338|310|330|370+378|403+235|501}}
}}
|Section8={{Chembox Related
| OtherFunction_label = cyclic ketones
| OtherAnions =
| OtherCations =
| OtherCompounds =
| OtherFunction = Cyclohexanone, Cyclooctanone, Tropinone }}
}}
Cycloheptanone, (CH2)6CO, is a cyclic ketone also referred to as suberone. It is a colourless volatile liquid. Cycloheptanone is used as a precursor for the synthesis of pharmaceuticals.
Synthesis
In 1836, French chemist Jean-Baptiste Boussingault first synthesized cycloheptanone from the calcium salt of dibasic suberic acid. The ketonization of calcium suberate yields calcium carbonate and suberone:{{ cite book | author = Thorpe, T. E. | title = A Dictionary of Applied Chemistry | year = 1912 | lccn = 12009914 }}
:Ca(O2C(CH2)6CO2) → CaCO3 + (CH2)6CO
Cycloheptanone is still produced by the cyclization and decarboxylation of suberic acid or suberic acid esters. This reaction is typically conducted in the gas phase at 400–450 °C over alumina doped with zinc oxide or cerium oxide.{{ Ullmann | author = Siegel, H. | author2 = Eggersdorfer, M. | title = Ketones | doi = 10.1002/14356007.a15_077 }}
Cycloheptanone is also produced by the reaction of cyclohexanone with sodium ethoxide and nitromethane. The resulting sodium salt of 1-(nitromethyl)cyclohexanol is added to acetic acid and shaken with hydrogen gas in the presence of W-4 Raney nickel catalyst. Sodium nitrite and acetic acid are then added to give cycloheptanone.{{ OrgSynth | prep = cv4p0221 | author = Dauben, H. J. Jr. | author2 = Ringold, H. J. | author3 = Wade, R. H. | author4 = Pearson, D. L. | author5 = Anderson, A. G. Jr. | title = Cycloheptanone | year = 1954 | volume = 34 | pages = 19 | collvol = 4 | collvolpages = 221 }}
Cycloheptanone is also prepared by ring expansion of cyclohexanone with diazomethane as the methylene source.
Uses and reactions
Cycloheptanone is a precursor to bencyclane, a spasmolytic agent and vasodilator. Pimelic acid is produced by the oxidative cleavage of cycloheptanone.{{ Ullmann | author = Cornils, B. | author2 = Lappe, P. | title = Dicarboxylic Acids, Aliphatic | doi = 10.1002/14356007.a08_523.pub2 }} Dicarboxylic acids such as pimelic acid are useful for the preparation of fragrances and certain polymers.{{cite web | title = Dicarboxylic Acids | url = http://www.cyberlipid.org/fa/acid0004.htm | publisher = cyberlipids.org | access-date = 2011-04-26 | archive-url = https://web.archive.org/web/20110907093548/http://www.cyberlipid.org/fa/acid0004.htm | archive-date = 2011-09-07 | url-status = dead }}
Several microorganisms, including Mucor plumbeus, Mucor racemosus, and Penicillium chrysogenum, have been found to reduce cycloheptanone to cycloheptanol. These microorganisms have been investigated for use in certain stereospecific enzymatic reactions.{{ cite journal |author1=Lemiere, G. L. |author2=Alderweireldt, F. C. |author3=Voets, J. P. | title = Reduction of cycloalkanones by several microorganisms | journal = Zeitschrift für Allgemeine Mikrobiologie | year = 1975 | volume = 15 | issue = 2 | pages = 89–92 | doi = 10.1002/jobm.19750150204 }}