Novel Synthesis of Benzalacetone Analogues of Naphth[<i>a</i>]azulenes by Intramolecular Tropylium Ion-Mediated Furan Ring-Opening Reaction and X-ray Investigation of a Naphth[1,2-<i>a</i>]azulene Derivative
作者:Kimiaki Yamamura、Shizuka Kawabata、Takatomo Kimura、Kazuo Eda、Masao Hashimoto
DOI:10.1021/jo051409f
日期:2005.10.1
Benzalacetone analogues of naphth[1,2-a]azulene (8), naphth[2,1-a]azulene (13), and naphth[2,3-a]azulene (18) were synthesized from 2-(5-methyl-2-furyl)-1-tropylionaphthalene (7), 1-(5-methyl-2-furyl)-2-tropylionaphthalene (12), and 2-(5-methy-2-furyl)-3-tropylionaphthalene (17), respectively. The synthetic method is based on furan ring-opening reaction by the intramolecular electrophilic attack of
由2-(5-)合成萘[1,2- a ] azulene(8),萘[2,1- a ] azulene(13)和萘[2,3- a ] azulene(18)的苯丙酮丙酮类似物。甲基-2-呋喃基)-1-对苯二甲酰基(7),1-(5-甲基-2-呋喃基)-2-对苯二甲酰基萘(12)和2-(5-甲基-2-呋喃基)-3-对苯二甲酰基萘(17)。合成方法基于对呋喃离子的分子内亲电攻击而引起的呋喃开环反应。萘[1,2- a ] az杂烯衍生物的单晶X射线研究(8)表明,其四环体系的平面度与苯并[ c ]菲(四螺旋)相似。在晶体中发现了一个中心对称相关的二聚体结构,就像羧酸分子一样,但通过C O···H-C氢键。还发现减少了七元环中的键长交替。