Cobalt−NHC Catalyzed C(sp
<sup>2</sup>
)−C(sp
<sup>3</sup>
) and C(sp
<sup>2</sup>
)−C(sp
<sup>2</sup>
) Kumada Cross‐Coupling of Aryl Tosylates with Alkyl and Aryl Grignard Reagents
作者:Aleksandra Piontek、Wioletta Ochędzan‐Siodłak、Elwira Bisz、Michal Szostak
DOI:10.1002/cctc.202001347
日期:2021.1.12
cross‐coupling of aryl tosylates with alkyl and aryl Grignard reagents is reported. The catalytic system uses CoF3 and NHCs (NHC=N‐heterocyclic carbene) as ancillary ligands. The reaction proceeds via highly selective C−O bond functionalization, leading to the corresponding products in up to 98 % yield. The employment of alkyl Grignard reagents allows to achieve a rare C(sp2)−C(sp3) cross‐coupling of
据报道,芳基甲苯磺酸盐与烷基和芳基格氏试剂首次进行钴催化的交叉偶联。催化系统使用CoF 3和NHC(NHC = N-杂环卡宾)作为辅助配体。该反应通过高度选择性的C-O键官能化进行,从而以高达98%的收率得到相应的产物。烷基格氏试剂的使用允许实现C-O亲电试剂的罕见C(sp 2)-C(sp 3)交叉偶联,避免了异构化和消除β-氢化物的问题。芳基格氏试剂的使用导致联芳基的形成。通过利用催化系统的正交选择性,C-O交叉偶联为顺序交叉偶联奠定了基础。