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Updated: Aug 4, 2025

Chemoselective Preparation of 1-Iodoalkynes, 1,2-Diiodoalkenes, and 1,1,2-Triiodoalkenes Based on the Oxidative Iodination of Terminal Alkynes

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Published on: September 12, 2018

1,1-非替代的氧化重新排列为

Qiang Feng¹, Qian Wang¹, Jieping Zhu¹

¹Laboratory of Synthesis and Natural Products (LSPN), Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH5304, CH-1015 Lausanne, Switzerland.

Science (New York, N.Y.)

|March 30, 2023

概括

这项研究引入了一种新的催化反应,用于从1,1-非替代中合成甲基,克服现有方法的局限性. 新的Pd^II/Pd^IV循环可以实现更广泛的基板范围和功能组耐受性.

科学领域:

有机化学
催化剂
有机金属化学

背景情况:

瓦克尔工艺是一种 (Pd) 催化氧化到甲基的过程,通常涉及单替代和Pd^II/Pd⁰循环与β-化物.
这种已确定的机制不适合从1,1-非替代合成.
对于1,1-非替代的现有方法,如Pd^II中间体的半重排,仅限于特定的应力循环系统.

研究的目的:

开发一种新型的催化方法,用于从1,1-非替代中合成甲基基.
克服目前这种类型化合物的合成策略的局限性
建立适用于更广泛的基质的新催化循环.

主要方法:

在Pd^II和Pd^IV氧化状态之间运行的催化循环的设计和实施.
在催化循环中利用一个关键的1,2-基/Pd^IV二基重组步骤.
测试反应与多种功能组和多种基质的兼容性,包括线性和循环系统.

主要成果:

一个新的Pd^II/Pd^IV催化循环成功地设计并证明了从1,1-非替代中合成.
该反应具有广泛的功能组耐受性,适用于线性烯和甲基环,包括宏循环.
观察到的区域选择性有利于更替代的碳的迁移,并且对β-碳基组发现了显著的定向效应.

结论:

已经确定了一种新的多功能催化合成途径,从1,1-非替代中生成甲基基.
开发的Pd^II/Pd^IV催化循环,具有二极管重组,扩大了介导功能化的范围.
该反应的广泛适用性和观察到的选择性为有机合成提供了有价值的新工具.

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