Zhu Ren-Yi, Wang Cong-Shuai, Zheng Jian, Shi Feng, Tu Shu-Jiang
School of Chemistry & Chemical Engineering, and Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials, Jiangsu Normal University , Xuzhou, 221116, China.
J Org Chem. 2014 Oct 3;79(19):9305-12. doi: 10.1021/jo5018469. Epub 2014 Sep 17.
The first organocatalytic asymmetric inverse-electron-demand 1,3-dipolar cycloaddition (IED 1,3-DC) of N,N'-cyclic azomethine imines has been established in the presence of chiral phosphoric acid. This approach assembles N,N'-cyclic azomethine imines and o-hydroxystyrenes into chiral N,N-bicyclic pyrazolidin-3-one derivatives with the creation of two stereogenic centers, one of which is quaternary, in excellent diastereoselectivities and good enantioselectivities (up to >95:5 dr, 88:12 er). The investigation of the activation mode of the reaction revealed that the dual hydrogen-bonding interaction between the two substrates and the catalyst together with the conjugative effect initiated by the o-hydroxyl group played a crucial role in the designed IED 1,3-DC. This study will not only greatly enrich the underdeveloped research potential of catalytic asymmetric IED 1,3-DCs but will also facilitate the design of other enantioselective IED 1,3-DCs based on different activation modes.
在手性磷酸存在下，首次实现了N，N'-环甲亚胺亚胺的有机催化不对称逆电子需求1,3-偶极环加成反应（IED 1,3-DC）。该方法将N，N'-环甲亚胺亚胺与邻羟基苯乙烯组装成手性N，N-双环吡唑烷-3-酮衍生物，形成两个立体ogenic中心，其中一个是季碳中心，具有优异的非对映选择性和良好的对映选择性（高达>95:5 dr，88:12 er）。对反应活化模式的研究表明，两种底物与催化剂之间的双重氢键相互作用以及邻羟基引发的共轭效应在设计的IED 1,3-DC中起着关键作用。这项研究不仅将极大地丰富催化不对称IED 1,3-DC尚未充分开发的研究潜力，还将促进基于不同活化模式的其他对映选择性IED 1,3-DC的设计。
