Das Sayantani, Zhu Chendan, Demirbas Derya, Bill Eckhard, De Chandra Kanta, List Benjamin
Max-Planck-Institut für Kohlenforschung, D-45470 Mülheim an der Ruhr, Germany.
Max-Planck-Institut für Chemische Energiekonversion, D-45470 Mülheim an der Ruhr, Germany.
Science. 2023 Feb 3;379(6631):494-499. doi: 10.1126/science.ade8190. Epub 2023 Jan 19.
Photoredox catalysis enables distinctive and broadly applicable chemical reactions, but controlling their selectivity has proven to be difficult. The pursuit of enantioselectivity is a particularly daunting challenge, arguably because of the high energy of the activated radical (ion) intermediates, and previous approaches have invariably required pairing of the photoredox catalytic cycle with an additional activation mode for asymmetric induction. A potential solution for photoredox reactions proceeding via radical ions would be catalytic pairing with enantiopure counterions. However, although attempts toward this approach have been described, high selectivity has not yet been accomplished. Here we report a potentially general solution to radical cation-based asymmetric photoredox catalysis. We describe organic salts, featuring confined imidodiphosphorimidate counteranions that catalyze highly enantioselective [2+2]-cross cycloadditions of styrenes.
光氧化还原催化能够实现独特且广泛适用的化学反应，但事实证明控制其选择性很困难。对映选择性的追求是一项特别艰巨的挑战，这可以说是因为活化自由基（离子）中间体的能量很高，而且以前的方法总是需要将光氧化还原催化循环与用于不对称诱导的额外活化模式相结合。对于通过自由基离子进行的光氧化还原反应，一种可能的解决方案是与对映体纯抗衡离子进行催化配对。然而，尽管已经描述了针对这种方法的尝试，但尚未实现高选择性。在这里，我们报告了一种基于自由基阳离子的不对称光氧化还原催化的潜在通用解决方案。我们描述了有机盐，其具有受限的亚氨基二磷酸亚胺酸根抗衡阴离子，可催化苯乙烯的高度对映选择性[2+2]交叉环加成反应。
