Coupling of Reformatsky Reagents with Aryl Chlorides Enabled by Ylide‐Functionalized Phosphine Ligands
作者:Zhiyong Hu、Xiao‐Jing Wei、Jens Handelmann、Ann‐Katrin Seitz、Ilja Rodstein、Viktoria H. Gessner、Lukas J. Gooßen
DOI:10.1002/anie.202016048
日期:2021.3.15
organozinc reagents with aryl electrophiles using a cyclohexyl‐YPhos ligand bearing an ortho‐tolyl‐substituent in the backbone. This highly electron‐rich, bulky ligand enables the use of aryl chlorides in room temperature couplings of Reformatsky reagents. The reaction scope covers diversely functionalized arylacetic and arylpropionic acid derivatives. Aryl bromides and chlorides can be converted selectively
芳基氯化物与Reformatsky试剂的偶联是构建α-芳基酯的理想策略,但由于各种可能的副反应带来许多挑战,到目前为止,在基质范围上已受到很大的限制。现在,通过调整内酯官能化的膦以满足Negishi联轴器的要求,克服了这一局限性。使用在主链上带有邻甲苯基取代基的环己基-YPhos配体,在钯催化的有机锌试剂与芳基亲电试剂的芳基化中达到了创纪录的活性。这种高度电子富集的庞大配体使得可以在Reformatsky试剂的室温偶联中使用芳基氯化物。反应范围包括各种官能化的芳酸和芳基丙酸衍生物。