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Updated: Jun 30, 2025

Preparation and Use of Samarium Diiodide SmI2 in Organic Synthesis: The Mechanistic Role of HMPA and NiII Salts in the Samarium Barbier Reaction

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Published on: February 4, 2013

通过萨马里二氧化物对5-阿里-2-的灾难选择性脱奥马化循环 - - 一个计算分析

Luca Steiner^1,2, Andreas J Achazi^3,4, Anne-Marie Kelterer²

¹Institut für Chemie und Biochemie, Freie Universität Berlin, Arnimallee 22, 14195, Berlin, Germany.

Chemistry (Weinheim an der Bergstrasse, Germany)

|March 21, 2024

概括

这项研究使用密度函数理论来研究二氧化促进的循环. 动力控制,受到硬质效应的影响,以及一个涉及两个SmI2部分的修改机制,决定了双循环产品的形成.

科学领域:

有机化学有机化学
计算化学的计算化学
物理化学物理化学

背景情况:

二氧化 (SmI2) 是有机合成中的多功能还原剂.
循环反应对于构建复杂的分子架构至关重要.
了解反应机制是控制选择性的关键.

研究的目的:

阐明二氧化促进的5-arylpentan-2-ones循环的机制.
调查这些反应中控制区域和散列选择性的因素.
探索计算方法在预测反应结果中的作用.

主要方法:

密度函数理论 (DFT) 的计算.
使用小核心伪潜力,包括萨马里亚的f电子.
使用对辅溶剂效应的校正术语.
分析过渡状态能量和固态影响.

主要成果:

反应是通过单个电子转移 (SET) 进行的,其次是质子合电子转移 (PCET).
动力控制,而不是热力学控制,决定了产品的选择性.
萨马配体和基基群的立体效应显著影响立体选择性和区域选择性.
对于某些循环化,提出了一种涉及双金属SmI2复合物的修改机制.

结论:

DFT准确地预测了二氧化促进的循环运动的动力控制.
联体的硬质体质量对立体选择性至关重要.
对于产生螺旋化合物的反应,提出了一种涉及双金属复合物的新机制.

关键词:

亲爱的罗姆化反应反应密度函数理论密度函数理论电子转移是电子的转移.六甲基酸盐胺撒玛利亚 (Samararium) 是一个

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