Direct Enantioselective α-Allylation of Unfunctionalized Cyclic Ketones with Alkynes through Pd-Amine Cooperative Catalysis
作者:Jin Tu Danence Lee、Yu Zhao
DOI:10.1002/chem.201802273
日期:2018.7.5
in good to high enantiopurity. In this transformation, a chiral palladium complex containing the (S)‐DIFLUORPHOS ligand catalyzes the isomerization of alkynes into an electrophilic allylpalladium species, which is attacked by the enamine generated in situ from the condensation of (R)‐prolinol with the ketone substrate.
据报道,使用炔烃作为经济的选择试剂,首次对未官能化的环酮进行了直接对映选择性的α-烯丙基化反应。此转化过程使用市售的钯,手性双膦配体和手性胺催化剂进行的简单操作,并提供具有良好对映纯度的α-叔立体中心的有价值的酮。在此转化过程中,含有(S)-DIFLUORPHOS配体的手性钯络合物催化炔烃异构化为亲电烯丙基钯物种,并受到(R)-脯氨醇与酮底物缩合的原位生成的烯胺的攻击。