Generation of Fused Seven-Membered Polycyclic Systems via Ring Expansion and Application to the Total Synthesis of Sesquiterpenoids
作者:Zhimin Xing、Bowen Fang、Shangwen Luo、Xingang Xie、Xiaolei Wang
DOI:10.1021/acs.orglett.2c01401
日期:2022.6.10
methods for synthesizing fused medium-sized bicyclo[m.n.0] ringsystems, including the benzo-cycloheptane systems, are still urgent. Herein we describe a base-induced ring expansion as a general strategy to construct a wide range of fused seven-membered ringsystems. The application of this method was demonstrated by the efficient total syntheses of two sesquiterpenoids, plecarpenene and plecarpenone
广泛存在于天然产物和分子药物中的七元多环结构是具有挑战性的合成靶标。然而,合成融合中型双环的方法[ m . n .0] 环系统,包括苯并环庚烷系统,仍然是紧迫的。在这里,我们将碱基诱导的环扩展描述为构建广泛的稠合七元环系统的一般策略。该方法的应用通过两种倍半萜类化合物 plecarpenene 和 plecarpenone 的高效全合成得到证明,两者均具有稠合的双环 [5.3.0] 癸烷骨架。
Catalytic Enantioselective Nucleophilic Addition to Arynes by a New Quaternary Guanidinium Salt-Based Phase-Transfer Catalyst
作者:Guihua Pan、Maoping Pu、Hongyu Wang、Meijia Ying、Yi Li、Shunxi Dong、Xiaoming Feng、Xiaohua Liu
DOI:10.1021/jacs.3c09594
日期:2023.12.6
in situ generated fluoride-based chiral phase-transfer catalyst. In this study, we present a catalytic enantioselective nucleophilicaddition reaction involving arynes, utilizing an amino amide-based guanidinium salt QG•X. Furthermore, we demonstrate the broad compatibility of this reaction with various arynes and cyclic/acyclic β-keto amides, leading to the creation of diverse α-aryl quaternary stereocenters
Zirconium‐Salan Catalyzed Enantioselective
<i>α</i>
‐Hydroxylation of
<i>β</i>
‐Keto Esters
作者:Jie Chen、Haiyang Gu、Xueying Zhu、Wonwoo Nam、Bin Wang
DOI:10.1002/adsc.202000290
日期:2020.7.29
C2‐symmetric salan ligands and cumene hydroperoxide as an oxidant, affording synthetically valuable hydroxylation products in high yields (up to 99%) with excellent enantioselectivities (up to 99% ee) under mild reaction conditions. In mechanistic studies, we have shown that (1) a Zr(IV)‐salan complex was generated in situ as the active catalyst responsible for the chiralinduction, (2) the transfer