A Unified Catalytic Asymmetric (4+1) and (5+1) Annulation Strategy to Access Chiral Spirooxindole‐Fused Oxacycles
作者:Min Gao、Yanshu Luo、Qianlan Xu、Yukun Zhao、Xiangnan Gong、Yuanzhi Xia、Lin Hu
DOI:10.1002/anie.202105282
日期:2021.9
A unified catalyticasymmetric (N+1) (N=4, 5) annulation reaction of oxindoles with bifunctional peroxides has been achieved in the presence of a chiral phase-transfer catalyst (PTC). This general strategy utilizes peroxides as unique bielectrophilic four- or five-atom synthons to participate in the C−C and the subsequent umpolung C−O bond-forming reactions with one-carbon unit nucleophiles, thus providing
在手性相转移催化剂 (PTC) 的存在下,已经实现了羟吲哚与双官能过氧化物的统一催化不对称 ( N +1) ( N =4, 5) 环化反应。这种通用策略利用过氧化物作为独特的双亲电四原子或五原子合成子参与 C−C 和随后与单碳单元亲核试剂的 umpolung C−O 键形成反应,从而提供了一种独特的方法来获得有价值的手性螺吲哚-四氢呋喃和-四氢吡喃在温和条件下具有良好的产率和高对映选择性。进行 DFT 计算以合理化高对映选择性的起源。还证明了所得产物的克级合成和合成效用。
An unprecedented protocol for the synthesis of 3-hydroxy-3-phenacyloxindole derivatives with indolin-2-ones and α-substituted ketones
An unprecedented reaction between indolin-2-ones and α-substituted ketones has been developed. Using this protocol, a wide range of biologically important 3-hydroxy-3-phenacyloxindole derivatives could be obtained in good yield (up to 93%) under mild reaction conditions. A possible mechanism of this reaction was tentatively proposed based on some control experiments and MS spectrometry analysis.
A new, practical synthesis of the antirheumatic oxindole derivative, tenidap, has been elaborated. The new approach has initiated studies on the mechanism of the acylation reactions of oxindoles. Methods have been developed for the synthesis of 1-[alkoxy(or aryloxy)carbonyl]- and 1,3-di[alkoxy(or aryloxy)carbonyl]oxindoles starting from oxindoles. The route designed for tenidap has provided a facile
Phase-Transfer-Catalyzed Asymmetric Annulations of Alkyl Dihalides with Oxindoles: Unified Access to Chiral Spirocarbocyclic Oxindoles
作者:Min Gao、Yongyi Li、Xuemin Li、Lin Hu
DOI:10.1021/acs.orglett.1c04174
日期:2022.1.28
A general phase-transfer-catalyzed asymmetric (n+1) (n = 4 or 5) annulation reaction, featuring the direct coupling of simple oxindoles with alkyl dihalides that are allylic/benzylic and non-allylic/benzylic, has been developed to provide previously inaccessible cyclopentane- and cyclohexane-fused spirooxindole scaffolds with high yields and enantioselectivities (88–95% ee). Along with a broad scope
已开发出一种通用的相转移催化不对称 ( n +1) ( n = 4 或 5) 环化反应,其特点是简单的羟吲哚与烯丙基/苄基和非烯丙基/苄基的烷基二卤化物直接偶联,以提供以前无法获得的环戊烷和环己烷融合的螺氧吲哚支架具有高产率和对映选择性(88-95% ee)。除了广泛的范围和温和的条件外,新协议还可以对药物 ubrogepant 的核心进行两步和克级合成。
Asymmetric Organocatalytic [4 + 1] Annulations: Enantioselective Construction of Multifunctionalized Spirocyclopentane Oxindoles Bearing α,α-Disubstituted α-Amino-β-keto Esters
作者:Chuan-Chuan Wang、Jian Huang、Xin-Hao Li、Søren Kramer、Guo-Qiang Lin、Xing-Wen Sun
DOI:10.1021/acs.orglett.8b00927
日期:2018.5.18
α-disubstituted α-amino-β-keto esters was achieved through [4 + 1] annulation of oxindoles and α-imine-β-oxo-γ,δ-unsaturated esters under mild conditions in good yields (up to 82%) and stereoselectivities (up to >20:1 dr, 96% ee). The reaction is amenable to gram scale synthesis using catalyst loading as low as 1 mol %. The corresponding chiral α,α-disubstituted α-amino-β-keto esters could be easily transformed
通过在温和的条件下,于[4 +1]环化吲哚和α-亚胺-β-氧代-γ,δ-不饱和酯,可以实现具有α,α-二取代的α-氨基-β-酮基酯的螺硫辛酯的高对映选择性。良率(高达82%)和立体选择性(高达> 20:1 dr,96%ee)。该反应适合于使用低至1mol%的催化剂负载进行克规模的合成。相应的手性α,α-二取代的α-氨基-β-酮基酯可以很容易地转化为环戊[ b ]吲哚衍生物,而不会破坏对映体纯度。