an·​nu·​lene | \ ˈan-yə-ˌlēn How to pronounce annulene (audio) \
plural annulenes

Definition of annulene

: any of a class of completely conjugated cyclic hydrocarbons (such as benzene or cyclooctatetraene) In 1991, a temperate rainforest near Puerto Montt in central Chile yielded a fungus that made annulene, a hydrocarbon that has a history going back to the first formulations of rocket fuel.— Buzzy Gordon, Americas, 1 Nov. 2007 This class of annulenes, which have few hydrogens and are considered high-energy because of their numerous triple bonds, has also drawn attention as potential precursors to new carbon allotropes.— Elizabeth Wilson, Chemical & Engineering News, 3 Mar. 1997

Note: Annulenes have the general chemical formula CnHn where n is an even number or CnHn + 1 if n is an odd number.

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First Known Use of annulene

1962, in the meaning defined above

History and Etymology for annulene

Latin annulus “ring” + -ene

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The first known use of annulene was in 1962

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Cite this Entry

“Annulene.” Dictionary, Merriam-Webster, Accessed 5 Aug. 2020.

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