Cycloheptanone

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.

Cycloheptanone

Names
Preferred IUPAC name Cycloheptanone
Other names Suberone
Identifiers
CAS Number	502-42-1 Y
3D model (JSmol)	Interactive image
ChEMBL	ChEMBL18607 Y
ChemSpider	9971 Y
ECHA InfoCard	100.007.216
EC Number	207-937-6
PubChem CID	10400
UNII	QH80295937 Y
CompTox Dashboard (EPA)	DTXSID8060113
InChI InChI=1S/C7H12O/c8-7-5-3-1-2-4-6-7/h1-6H2 Y Key: CGZZMOTZOONQIA-UHFFFAOYSA-N Y
SMILES O=C1CCCCCC1
Properties
Chemical formula	C7H12O
Molar mass	112.172 g·mol−1
Appearance	Colorless liquid
Density	0.949 g/cm3 (20 °C)[1]
Boiling point	179 to 181 °C (354 to 358 °F; 452 to 454 K)[1]
Solubility in water	Insoluble
Hazards
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H226, H302, H318
Precautionary statements	P210, P233, P240, P241, P242, P243, P264, P270, P280, P301+P312, P303+P361+P353, P305+P351+P338, P310, P330, P370+P378, P403+P235, P501
Flash point	56 °C (133 °F; 329 K)[2]
Related compounds
Related cyclic ketones	Cyclohexanone, Cyclooctanone, Tropinone
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

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:^[3]

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.^[4]

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.^[5]

Cycloheptanone is also prepared by ring expansion of cyclohexanone with diazomethane as the methylene source.^[5]

Uses and reactions

Cycloheptanone is a precursor to bencyclane, a spasmolytic agent and vasodilator.^[4] Pimelic acid is produced by the oxidative cleavage of cycloheptanone.^[6] Dicarboxylic acids such as pimelic acid are useful for the preparation of fragrances and certain polymers.^[7]

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.^[8]