文献类型：期刊文献

英文题名：Ir/Bronsted acid dual-catalyzed asymmetric synthesis of bisbenzannulated spiroketals and spiroaminals from isochroman ketals

作者：Chen, Yang[1];Yan, Hui[1];Zheng, Hanliang[2];Deng, Wei-Ping[2];Li, Zhong[1];Yang, Wu-Lin[1]

机构：[1]East China Univ Sci & Technol, Shanghai Key Lab Chem Biol & Sch Pharm, 130 Meilong Rd, Shanghai 200237, Peoples R China;[2]Zhejiang Normal Univ, Coll Chem & Mat Sci, Key Lab Minist Educ Adv Catalysis Mat, Jinhua 321004, Peoples R China

年份：2024

卷号：11

期号：20

起止页码：5831

外文期刊名：ORGANIC CHEMISTRY FRONTIERS

收录：;WOS:【SCI-EXPANDED(收录号:WOS:001302717500001)，CCR-EXPANDED(收录号:WOS:001302717500001)】；

基金：This work was supported by the National Natural Science Foundation of China (22171081), Shanghai Rising-Star Program (23QA1402600), Natural Science Foundation of Shanghai Municipality (23ZR1416700), Shanghai Agriculture Applied Technology Development Program (T2023309), and Fundamental Research Funds for the Central Universities (JKY01241718). Hui Yan thanks Lin Li for the help on the preparation of the substrates. The authors thank the Research Center of Analysis and Test of East China University of Science and Technology for the help on HRMS and NMR analyses.

语种：英文

摘要：Herein, we reported an Ir/Br & oslash;nsted acid dual-catalyzed asymmetric cascade reaction of 2-(1-hydroxyallyl)-phenols with isochroman ketals to produce bisbenzannulated spiroketals in high efficiency with generally high diastereo- and enantioselectivities (up to 17 : 1 dr, >99% ee). The procedure involved the generation of exocyclic enol ethers from isochroman ketals through Bronsted acid catalysis, followed by an Ir-catalyzed enantioselective allylation/spiroketalization sequence with 2-(1-hydroxyallyl)-phenols. Mechanistic investigations and theoretical calculations revealed that chiral iridium catalyst controlled the enantioselectivity, while the high diastereoselectivity was attributed to a Br & oslash;nsted acid-promoted thermodynamically controlled epimerization process. Furthermore, the asymmetric cascade reaction involving 2-(1-hydroxyallyl)anilines was found to be applicable for synthesizing optically pure bisbenzannulated spiroaminals. Additionally, some of the bisbenzannulated spiroketal products showed promising inhibitory activity against Rhizoctonia solani, suggesting their potential applications in agrochemical discovery.