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|Section2= |Section7= }} Corannulene is a polycyclic aromatic hydrocarbon with chemical formula C20H10. The molecule consists of a cyclopentane ring fused with 5 benzene rings, so another name for it is ()circulene. It is of scientific interest because it is a geodesic polyarene and can be considered a fragment of buckminsterfullerene. Due to this connection and also its bowl shape, corannulene is also known as a buckybowl. Corannulene exhibits a bowl-to-bowl inversion with an inversion barrier of 10.2 kcal/mol (42.7 kJ/mol) at −64 °C. ==Synthesis== Several synthetic routes exist to corannulene. Flash vacuum pyrolysis techniques generally have lower chemical yields than solution-chemistry syntheses, but offer routes to more derivatives. Corannulane was first isolated in 1966 by multistep organic synthesis. A flash vacuum pyrolysis method followed in 1991. One synthesis based on solution chemistry consists of a nucleophilic displacement–elimination reaction of an octabromide with potassium hydroxide: : The bromine substituents are removed with an excess of ''n''-butyllithium. Much effort is directed at functionalization of the corannulene ring with novel functional groups such as ethynyl groups,〔 ether groups, thioether groups, platinum functional groups, aryl groups, phenalenyl fused and indeno extensions. and ferrocene groups. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「corannulene」の詳細全文を読む スポンサード リンク
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