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通过双混合 DFT 调查 [3]Cumulenes 的反应性和选择性

Abdulkader Baroudi¹, Wejdan E Matar¹, Sami Tlais¹

¹College of Engineering and Technology, American University of the Middle East, Egaila 54200, Kuwait.

|October 14, 2024

概括

这项研究研究了 [3]烯的反应性,揭示了替代剂如何控制反应选择性. 结果显示,在 [4 + 2] 循环加法中,终端债券的动力偏好和中央债券的热力学偏好.

科学领域:

有机化学有机化学
理论化学理论化学
计算化学的计算化学

背景情况:

[3]烯是独特的不和碳化合物,具有合成潜力.
了解它们的反应性对于利用它们的合成实用性至关重要.
控制 [3] 烯的反应选择性仍然是一个挑战.

研究的目的:

理论上研究替代 [3] 烯的反应性.
确定控制反应选择性的关键因素.
探索替代剂对循环添加反应的影响.

主要方法:

使用基于密度的局部对自然轨道合集群,以同一性近似的分辨率 (DLPNO-ωB97X-2/Def2-QZVPP) 进行理论计算.
分析了 [4 + 2] 循环加法反应的反应途径和能量概况.
研究了替代剂的电子和硬质效应的作用.

主要成果:

在涉及 [3]cumulenes 的三个 π 键的反应中表现出中度至高的选择性.
确定了对终端 π 键的 [4 + 2] 循环加法的动态有利性.
观察到的热力学有利性在中心的π键上为循环加法.
预测在特定的四位置换 [3] 烯中增强和逆转运动选择性.
由于扭曲能量的减少,在四[3]烯中解化反转选择性.
预测了由热力学因素驱动的四聚甲[3]烯的类似选择性.

结论:

替代效应显著影响 [3]烯反应的区域选择性.
动力和热力学控制之间的相互作用决定了反应结果.
理论见解为设计 [3] 合成应用量身定制的反应性烯提供了基础.
需要对动力学因素进行进一步的研究,以提高稳定性和实际应用.

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