Chiral acetyl-protected aminoethyl quinoline (APAQ), pyridine and imazoline ligands are disclosed that enable Pd (II)-catalyzed enantioselective arylation or heteroarylation of ubiquitous prochiral β-methylene C—H bonds of aliphatic amides offers an alternative disconnection for constructing β-chiral centers. Systematic tuning of the ligand structure reveals that a six-membered instead of a five-membered chelation of these types of ligands with the Pd(II) is important for accelerating the C(sp3)-H activation thereby achieving enantioselectivity for quinoline and pyridine ligands.
本研究公开了手性乙酰基保护的
氨基乙基
喹啉 (APAQ)、
吡啶和
咪唑啉配体,这些
配体能够在
钯(II)催化下对无处不在的脂肪族酰胺的原手性 β-亚甲基 C-H 键进行对映选择性芳基化或杂芳基化,为构建 β-手性中心提供了另一种断开方式。
配体结构的系统调整表明,这些
配体与 Pd(II) 的六元螯合而非五元螯合对于加速 C(sp3)-H 活化非常重要,从而实现了
喹啉和
吡啶配体的对映选择性。