Cyclononyne

Cyclononyne is an organic compound with the chemical formula C₉H₁₄.^[1] Its molecule has a ring of nine carbon atoms, connected by eight single bonds and one triple bond.^[2]

Cyclononyne

Names
Preferred IUPAC name Cyclononyne
Identifiers
CAS Number	6573-52-0 Y
3D model (JSmol)	Interactive image
Beilstein Reference	1920441
ChEBI	CHEBI:37816
ChemSpider	122379
PubChem CID	138773
CompTox Dashboard (EPA)	DTXSID60215936
InChI InChI=1S/C9H14/c1-2-4-6-8-9-7-5-3-1/h1-7H2 Key: WXUICIMSUQBFMI-UHFFFAOYSA-N
SMILES C1CCCC#CCCC1
Properties
Chemical formula	C9H14
Molar mass	122.211 g·mol−1
Density	0.8972 g/cm³
Boiling point	68 °C (154 °F; 341 K) at 15 Torr
Related compounds
Related compounds	Cyclopentyne Cyclooctyne Cyclononene Cyclononane Cyclodecyne
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Synthesis

The compound can be prepared by converting 1,2-cyclononanedione to the corresponding dihydrazone via hydrazine and then reacting it with mercuric oxide in the presence of sodium sulfate.^[3][4] When 1,2-cyclononadiene is exposed to light in a dilute pentane solution, it will produce a small amount of cyclononyne and other C₉ cycloolefin products via the intermediate isomer of bicyclo[6.1.0]non-8-ene. Under the catalysis of a rhodium complex, it is refluxed with sulfur in butanone to obtain a dithiol derivative, which is then refluxed in o-dichlorobenzene and desulfurized to obtain a thiophene derivative.^[5]

Physical properties

It is reported that pyrolysis of cyclononyne at 600 °C will lead to forming 1,2,8-nonatriene and trans-bicyclo[4.3.0]nona-2-ene in a 1:0.9 ratio.^[6]