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Updated: Jul 19, 2025

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate

Published on: June 21, 2017

热激活的几何区域选择性E→Z异构化启用连合天的级联序列:实验和DFT研究

Jayanta Saha^1,2, Soumadip Banerjee³, Sidhartha Malo^1,2

¹Organic and Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, Jadavpur, Kolkata, 700032, India.

Chemistry (Weinheim an der Bergstrasse, Germany)

|August 9, 2023

概括

这项研究通过将其与循环化相结合,克服了热E→Z异构化挑战,产生没有光,酸或催化剂的γ-alkoxybutenolides. 隔离的中间体展示了区域选择性的热异构化.

科学领域:

有机化学有机化学
反应机制反应机制
立体化学是一种立体化学.

背景情况:

微观可逆性使结合基的热E→Z同质化复杂化.
传统方法通常需要光,酸或金属催化剂.

研究的目的:

为了规避热E→Z异构化中的可逆性问题.
开发一种无催化剂的方法来合成g-alkoxybutenolides.
研究区域选择性异构化和随后循环化的机制.

主要方法:

在酒精-托卢混合物中热激活线性结合的迪纳尔.
介质2Z,4E-同位素的分离和表征.
密度函数理论 (DFT) 计算用于研究反应路径和能量.

主要成果:

在热条件 (60-70°C) 下,成功地将二甲醇转化为γ-氧丁化物.
区域选择性2Z,4E-异构体的分离,证明了热力学上容易异构化 (ΔG <0).
DFT研究确定了半乙路径作为动力学上更喜欢的循环级联.

结论:

已经建立了一个针对区域选择性E→Z异构化和循环化级联的新策略.
该过程避免了恶劣的条件,提供了一个更绿色的合成方法.
了解电荷转移和非共价相互作用的作用解释了同位素稳定性.

关键词:

酒精类酒精类酒精类酒精类级联反应是一种级联反应.迪纳尔斯 (Dienal) 的时间异构化的异构化地区选择性地区选择性

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