Acid-catalyzed cyclization of anthracenol derivatives to homotriptycenes
Acid-catalyzed cyclization of anthracenol derivatives to homotriptycenes
复制标题
酸催化蒽酚衍生物环化为同三蝶烯
DOI：
10.1021/jo0526791
复制
发表时间：
2006-04-14
影响因子：
3.6
通讯作者：
Meier, H
中科院分区：
文献类型：
--
作者：
Gao, CM;Cao, DR;Meier, H
10-苄基-9，10-二氢蒽-9-醇在苯环上具有高电子密度，在酸存在下以几乎定量的产率与相应的高三蝶烯发生跨环闭环反应。由于起始化合物容易从9（10 H）-蒽酮获得，因此该方法代表了获得此类五环体系的最容易的途径。释放电子的甲氧基使分子内亲电取代在其帕拉。在没有这种活化的情况下，可以发生许多替代过程，即酸催化脱水成蒽衍生物，具有（R不等于H）或不具有（R = H）重排或仲醇的缩合反应成相应的酮和烃。
10-Benzyl-9,10-dihydroanthracen-9-ols, having high electron densities in the benzene ring, exhibit in the presence of acid a transannular ring closure to the corresponding homotriptycenes in almost quantitative yields. Since the starting compounds are easily accessible from 9(10H)-anthracenone, this process represents the most facile route to such pentacyclic systems. An electron-releasing methoxy group enables the intramolecular electrophilic substitution in its para position. In the absence of such an activation, a number of alternative processes can occur, namely the acid-catalyzed dehydration to anthracene derivatives with (R not equal H) or without (R = H) rearrangement or a disproportionation reaction of the secondary alcohol to the corresponding ketone and hydrocarbon.