Quantum Dot‐Catalyzed Photoreductive Removal of Sulfonyl‐Based Protecting Groups
Quantum Dot‐Catalyzed Photoreductive Removal of Sulfonyl‐Based Protecting Groups
复制标题
量子点催化光还原去除磺酰基保护基团
DOI：
10.1002/ange.202005074
复制
发表时间：
2020
影响因子：
--
通讯作者：
Weiss, Emily A.
中科院分区：
文献类型：
--
作者：
Perez, Kaitlyn A.;Rogers, Cameron R.;Weiss, Emily A.
该通讯描述了使用 CuInS2/ZnS 量子点 (QD) 作为光催化剂，用于芳基磺酰基保护酚的还原脱保护。对于一系列具有吸电子取代基的芳基磺酸盐，相应的苯基芳基磺酸盐的脱保护速率随着催化循环内两个电子转移的电化学势的降低而增加。含有羧酸（一种已知的 QD 结合基团）的底物的脱保护速率比根据转化电化学势预期的速率加快了十倍以上，这一结果表明亚稳态电子供体-受体复合物的形成提供了显着的动力学优势。这种去保护方法不会干扰常见的 NHBoc 或甲苯磺酰基保护基团，并且如雌酮底物所证明的那样，不会干扰邻近的酮，而邻近的酮通常容易受到用于此类反应的许多化学还原方法的影响。
This Communication describes the use of CuInS2/ZnS quantum dots (QDs) as photocatalysts for the reductive deprotection of aryl sulfonyl‐protected phenols. For a series of aryl sulfonates with electron‐withdrawing substituents, the rate of deprotection for the corresponding phenyl aryl sulfonates increases with decreasing electrochemical potential for the two electron transfers within the catalytic cycle. The rate of deprotection for a substrate that contains a carboxylic acid, a known QD‐binding group, is accelerated by more than a factor of ten from that expected from the electrochemical potential for the transformation, a result that suggests that formation of metastable electron donor–acceptor complexes provides a significant kinetic advantage. This deprotection method does not perturb the common NHBoc or toluenesulfonyl protecting groups and, as demonstrated with an estrone substrate, does not perturb proximate ketones, which are generally vulnerable to many chemical reduction methods used for this class of reactions.