A Practical Electrophilic Nitrogen Source for the Synthesis of Chiral Primary Amines by Copper-Catalyzed Hydroamination
作者:Sheng Guo、Jeffrey C. Yang、Stephen L. Buchwald
DOI:10.1021/jacs.8b10564
日期:2018.11.21
and practical method for the catalytic installation of the amino group across alkenes and alkynes has long been recognized as a significant challenge in synthetic chemistry. As the direct hydroamination of olefins using ammonia requires harsh conditions, the development of suitable electrophilic aminating reagents for formal hydroamination methods is of importance. Herein, we describe the use of 1
metal-hydride atom transfer (MHAT) to the olefin prior to carbofunctionalization with a cocatalyst, our mechanistic evidence points toward a nonradical reaction pathway that begins with site-selective carbonickelation across the C═C bond followed by hydridetransferusing alkoxide as the hydride source. Utility of the single-catalyst protocol is highlighted through the synthesis of medicinally relevant
Enantioselective Preparation of Arenes with β‐Stereogenic Centers: Confronting the 1,1‐Disubstituted Olefin Problem Using CuH/Pd Cooperative Catalysis
作者:Zhaohong Lu、Stephen L. Buchwald
DOI:10.1002/anie.202004414
日期:2020.9.7
Arenes with β‐stereogenic centers are important substructures in pharmaceuticals and natural products. We have developed an asymmetric anti‐Markovnikov hydroarylation of 1,1‐disubstituted olefins by dual palladium and copper hydride catalysis as a convenient and general approach to access these substructures. This efficient one‐step process addresses several limitations of the traditional stepwise
Design and Application of Hybrid Phosphorus Ligands for Enantioselective Rh-Catalyzed Anti-Markovnikov Hydroformylation of Unfunctionalized 1,1-Disubstituted Alkenes
作者:Cai You、Shuailong Li、Xiuxiu Li、Jialing Lan、Yuhong Yang、Lung Wa Chung、Hui Lv、Xumu Zhang
DOI:10.1021/jacs.8b00275
日期:2018.4.18
series of novel hybrid phosphorus ligands were designed and applied to the Rh-catalyzed enantioselective anti-Markovnikov hydroformylation of unfunctionalized 1,1-disubstituted alkenes. By employing the new catalyst, linear aldehydes with β-chirality can be prepared with high yields and enantioselectivities under mild conditions. Furthermore, catalyst loading as low as 0.05 mol % furnished the desired