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对π-基黄金复合物的核性添加:直接和间接路径的证据

Jessica Rodriguez¹, Marte Sofie Martinsen Holmsen¹, Yago García-Rodeja²

¹CNRS/Université Paul Sabatier, Laboratoire Hétérochimie Fondamentale et Appliquée (LHFA, UMR 5069), 118 Route de Narbonne, 31062 Toulouse Cedex 09, France.

Journal of the American Chemical Society

|July 26, 2021

概括

新发现的黄金 (III) π-化合物与β-二基酸盐具有复杂的反应性,与 (II) 路径不同. 机械研究揭示了竞争性的核爱攻击和独特的黄金介导转化.

科学领域:

有机金属化学
黄金催化
反应机制

背景情况:

π-合物复合物,特别是 π-合物 Pd (II) 种,在诸如 Tsuji-Trost 合物替代等反应中至关重要.
虽然黄金的π-复合物得到了很好的研究,但π-基Au (III) 复合物直到最近才被证明是真实的.
了解这些新型黄金复合物的反应性对于扩展合成方法至关重要.

研究的目的:

调查 (P,C) 循环金属化Au(III) π-合物复合物的与β-二基酸盐的反应性.
阐明所涉及的复杂机械路径,与已知的化学相对比.
描述反应过程中形成的中间体和产品.

主要方法:

合成和表征 (P,C) 循环金属化Au(III) π-基复合物.
用β-二乙烯酸盐进行反应研究.
使用核磁共振 (NMR) 光谱和密度功能理论 (DFT) 计算的详细机械研究.
关键中间体的晶体分析.

主要成果:

核友性攻击Au(III) π-合物复合物发生在中心,终端和金属位置,与Pd(II所见的主要终端攻击不同.
黄环和π-Au (I) 复合物的形成和表征.
确定了Au (III) σ-基复合体,并观察到它们对π-基系统和黄金中心的可逆添加.
通过C-C与的合,auracyclobutanes在黄金介导的环中被证明是相关的.

结论:

与β-二基酸盐的Au(III) π-基复合物的反应性在机理上很丰富,与Pd(II) 系统不同.
详细介绍了可逆核性添加的复杂相互作用,中间形成 (auracyclobutanes, σ-allyl复合物) 和最终的产品释放.
这项研究提供了对π-基Au (III) 复合物的综合反应性的全面了解,为黄金催化中的新合成应用开辟了道路.

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