Planar Chiral [2.2]Paracyclophane-Based Bisoxazoline Ligands: Design, Synthesis, and Use in Cu-Catalyzed Inter- and Intramolecular Asymmetric O–H Insertion Reactions
作者:Shinji Kitagaki、Shunsuke Murata、Kisaki Asaoka、Kenta Sugisaka、Chisato Mukai、Naoko Takenaga、Keisuke Yoshida
DOI:10.1248/cpb.c18-00519
日期:2018.10.1
insertion reactions of α-diazo esters. The reactivities and enantioselectivities of Cu complexes of the synthesized bisoxazoline ligands were lower than those of ligands without central chirality. However, planar chiral [2.2]paracyclophane-based bisoxazoline ligands with an inserted benzene spacer that had a sterically demanding isopropyl substituent showed good enantioselectivities in inter- and intramolecular
合成了直接连接到平面手性[2.2]对环环烷骨架上的中心手性双恶唑啉,并在Cu催化的α-重氮酯的分子间乙醇氢插入反应中将其作为不对称配体进行了评估。合成的双恶唑啉配体的Cu配合物的反应性和对映选择性低于没有中心手性的配体。然而,具有手性要求高的异丙基取代基的带有插入的苯间隔基的平面手性[2.2]对环环烷基双恶唑啉配体在分子间和分子内芳族OH插入反应中没有良好的对映选择性,而没有中心手性。