Toda Yasunori, Sato Kayo, Sato Kensuke, Nagasaki Kazuma, Nakajima Hirotaka, Kikuchi Ayaka, Sukegawa Kimiya, Suga Hiroyuki
Department of Materials Chemistry, Faculty of Engineering, Shinshu University 4-17-1 Wakasato, Nagano 380-8553, Japan.
Org Lett. 2022 Jul 8;24(26):4739-4744. doi: 10.1021/acs.orglett.2c01682. Epub 2022 Jun 20.
Chiral binaphthyldiimine-Ni(II)-catalyzed asymmetric 1,3-dipolar cycloaddition reactions between acyclic carbonyl ylides generated from donor-acceptor oxiranes and aldehydes are reported. Both aromatic and aliphatic aldehydes could be used as dipolarophiles, providing -1,3-dioxolanes with high diastereo- and enantioselectivities. On the basis of mechanistic studies, a monomeric chiral Ni(II) complex was hypothesized to act as the active species for the cycloaddition. The high levels of asymmetric induction are satisfactorily explained by a concerted-asynchronous -face approach of the aldehyde.
报道了手性联萘二亚胺-Ni(II)催化供体-受体环氧乙烷生成的无环羰基叶立德与醛之间的不对称1,3-偶极环加成反应。芳族和脂肪族醛均可用作亲偶极体，以高非对映选择性和对映选择性提供-1,3-二氧戊环。基于机理研究，推测单体手性Ni(II)配合物为环加成的活性物种。醛的协同-异步-面进攻令人满意地解释了高水平的不对称诱导。
