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Updated: May 15, 2025

Solid-phase Synthesis of [4.4] Spirocyclic Oximes

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Published on: February 6, 2019

螺旋cyclopropanes的硫介导环开放循环化,用于构建本佐[b]thiophene骨架

Hisanori Nambu^1,2, Yuki Seto¹, Yuta Onuki¹

¹Faculty of Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama, 930-0194, Japan.

Chemistry, an Asian journal

|May 14, 2025

概括

一种新方法通过区域选择性环开环循环化从环烯中合成[b]. 这种方法为宝贵的[b]衍生物提供了替代途径,没有复杂的原料.

科学领域:

有机化学有机化学
合成方法论合成方法论
异环化学异环化学

背景情况:

[b]thiophenes是重要的异环化合物,具有多种应用.
传统的[b]thiophenes合成往往需要复杂的,多替代的前体.
开发新的,高效的合成路线对于访问这些有价值的支架至关重要.

研究的目的:

开发一种新的合成方法来构建[b]thiophene骨架.
探索螺旋cyclopropane衍生物在[b]thiophene合成中的实用性.
建立一种替代方法,从易于获得的原料中合成[b]thiophenes.

主要方法:

区域选择性环开环循环化循环-1,3-二氧化-2-螺旋cyclopropanes和循环-1,3-二氧化-2-螺旋cyclopropanes.
使用硫化作为硫转移试剂.
随后进行酸性处理以获得四二[b]-4-one衍生物.

主要成果:

开发的协议成功合成了四乙[b]-4-one衍生物,产量良好至优异.
鉴定出环烯的螺旋环结构对于成功的环开环循环化至关重要.
随后的转化产生了2-替代的4-基[b]衍生物,没有不必要的氧化.

结论:

已经建立了一种新且高效的合成途径,从环烯前体中获得[b]thiophenes.
这种方法为现有的合成策略提供了有价值的替代方案,避免了难以制备的替代的需求.
这项工作代表了第一份关于使用环烯作为起始材料合成[b]thiophenes的报告.

关键词:

循环化循环化区域活动性区域活动性螺旋cyclopropanes 螺旋cyclopropanes 的使用方法硫的异循环环是硫的异循环环.合成方法合成方法

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