Base-Free Photoredox/Nickel Dual-Catalytic Cross-Coupling of Ammonium Alkylsilicates.
Base-Free Photoredox/Nickel Dual-Catalytic Cross-Coupling of Ammonium Alkylsilicates.
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DOI：
10.1021/jacs.5b10963
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发表时间：
2016-01-20
影响因子：
15
通讯作者：
Molander GA
中科院分区：
文献类型：
--
作者：
Jouffroy M;Primer DN;Molander GA
单电子金属转移被认为是在交叉偶联反应中将烷基温和转移到过渡金属催化剂上的一种技术。超配位硅酸盐代表了一类新的和改进的自由基前体，因为它们的低氧化电位和氧化时产生的无害副产物。在此，我们报道了烷基硅酸仲铵和烷基硅酸伯铵与（杂）芳基溴的交叉偶联，产率良好。无碱条件对两个伴侣都具有特殊的质子基团耐受性，允许未保护的伯胺和仲胺的交叉偶联。
Single-electron transmetalation is recognized as an enabling technology for the mild transfer of alkyl groups to transition metal catalysts in cross-coupling reactions. Hypercoordinate silicates represent a new and improved class of radical precursors because of their low oxidation potentials and the innocuous byproducts generated upon oxidation. Herein, we report the cross-coupling of secondary and primary ammonium alkylsilicates with (hetero)aryl bromides in good to excellent yields. The base-free conditions have exceptional protic group tolerance on both partners, permitting the cross-coupling of unprotected primary and secondary amines.