Synthesis, Stability, and Crystal Structure of an Azulenium Cation Containing an Adamantyl Group
作者:Mitsunori Oda、Nobue Nakajima、Nguyen Chung Thanh、Kazuhiro Kitahara、Ryuta Miyatake、Shigeyasu Kuroda
DOI:10.1002/ejoc.200800700
日期:2008.11
been obtained in similar reactions forming tetrahydroazulenones. The pKR+ value of the title cation was found to be 9.8, which is less than that expected by inductive stabilization from the number of carbons at the 1-position. The X-ray crystal structure of the title cation (ClO4– salt) reveals CH–O interactions and deformation of the azulenyl ion part.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim
从 1-乙酰基-1,3,5-环庚三烯的三甲基甲硅烷基烯醇醚开始,通过五步序列合成标题 1H-azulenium 阳离子,包括 Noyori-Mukaiyama 羟醛反应、Nazarov 环化、Shapiro 反应、和氢化物抽象。羟醛型加合物的纳扎罗夫反应导致形成了一种不寻常的双键位置异构体,这在形成四氢芴酮的类似反应中从未获得过。发现标题阳离子的 pKR+ 值为 9.8,这低于通过 1 位碳数诱导稳定所预期的值。标题阳离子 (ClO4– 盐) 的 X 射线晶体结构揭示了薁基离子部分的 CH–O 相互作用和变形。 (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)