Department of Chemistry, University of Alabama at Birmingham, 901 14th Street South, Birmingham, Alabama 35294, USA.
J Org Chem. 2011 Aug 5;76(15):5873-81. doi: 10.1021/jo200692c. Epub 2011 Jun 2.
A series of trityl-based photolabile hydroxyl protecting groups have been examined. These PPGs evolve from the traditional acid-labile trityl protecting group with proper electron-donating substituents. Structure-reactivity relationships have been explored. A m-dimethylamino group is crucial to achieve high photochemical deprotection efficiency. The o-hydroxyl group in 8 greatly improves the yield of the photochemical deprotection reaction, compared with the corresponding o-methoxyl-substituted counterpart 7. However, comparison between the photoreactions of 9 and 11 does not show similar structural relevance. The PPG in ether 1 (i.e., DMATr group) is structurally simple and easy to prepare and install. Its deprotection can be successfully carried out with irradiation of sunlight without requirement of photochemical devices.
已经研究了一系列基于三苯甲基的光不稳定羟基保护基团。这些 PPG 是从传统的酸不稳定三苯甲基保护基团发展而来，具有适当的供电子取代基。已经探索了结构-反应性关系。间二甲基氨基是实现高光化学脱保护效率的关键。与相应的邻甲氧基取代物 7 相比，8 中的邻羟基极大地提高了光化学脱保护反应的产率。然而，9 和 11 的光反应之间的比较并没有显示出类似的结构相关性。醚 1 中的 PPG（即 DMATr 基团）结构简单，易于制备和安装。其脱保护可以在阳光照射下成功进行，而不需要光化学设备。
