KnowraCyclopentadienyl anionLinked fromLinked fromThe 7 pages that link to Cyclopentadienyl anion, each with the reason it gives.All 7Broader topic 4Related 1Compared with 2AromaticityBroader topic: Its lone pair completes an aromatic electron count across the five-membered ring.Hückel's ruleBroader topic: Its lone pair completes a 4n + 2 count, making the ring aromatic.PyrroleCompared with: It matches pyrrole’s six-electron count but obtains the extra electron pair through negative charge on carbon.CyclobutadieneCompared with: Adding a carbon and an electron pair gives this related ring an aromatic electron count.Sodium hydrideBroader topic: Sodium hydride can deprotonate cyclopentadiene to prepare salts used in organometallic synthesis.CyclopentadieneBroader topic: Removing a ring proton creates the aromatic ligand central to many metal complexes.AzuleneRelated: Its aromatic five-membered ring helps illuminate one resonance contribution to azulene.