Enantioselective photoredox dehalogenative protonation
Enantioselective photoredox dehalogenative protonation
复制标题
对映选择性光氧化还原脱卤质子化
DOI：
10.1039/c9sc02000d
复制
发表时间：
2019-07-21
期刊：
影响因子：
8.4
通讯作者：
Jiang, Zhiyong
中科院分区：
文献类型：
--
作者：
Hou, Meimei;Lin, Lu;Jiang, Zhiyong
本文报道了一种新型的不对称质子化反应——对映选择性光氧化还原脱卤质子化反应。以手性h键催化剂和双氰吡嗪衍生的发色团（DPZ）光敏剂组成的协同催化体系为例，在可见光照射下，以仲胺为末端还原剂，以高收率获得了一系列具有手性C-F、C-Cl和C-Br键的环酮和无环酮，具有良好的对映选择性（高达100 - 99% ee）。鉴于卤化物的易接近性，本研究的成功将为构建手性α -叔羰基及其变体提供灵感。
We report an enantioselective photoredox dehalogenative protonation as a new type of asymmetric protonation. As a paradigm, with a cooperative catalytic system consisting of a chiral H-bonding catalyst and a dicyanopyrazine-derived chromophore (DPZ) photosensitizer that is irradiated with visible light, a range of cyclic and acyclic ketones with labile chiral secondary C-F, C-Cl and C-Br bonds at the alpha-position were obtained in high yields with good to excellent enantioselectivities (up to >99% ee) by using a secondary amine as the terminal reductant. Given the ready accessibility of halides, the success of this work should provide inspiration for constructing diverse chiral alpha-tertiary carbonyls and their variants.