10-(3,5-dimethoxyphenyl)benzo[h]quinoline | 1284234-06-5

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 喹啉及其衍生物
• 英文名称: 10-(3,5-dimethoxyphenyl)benzo[h]quinoline
• CAS: 1284234-06-5
• 化学式: C₂₁H₁₇NO₂
• 分子量: 315.371
• InChiKey: ZSIXPEQRJFYYQR-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  5
• 重原子数：
  24
• 可旋转键数：
  3
• 环数：
  4.0
• sp3杂化的碳原子比例：
  0.1
• 拓扑面积：
  31.4
• 氢给体数：
  0
• 氢受体数：
  3

反应信息

• 作为产物：
  描述：

  、 间苯二酚 在 溶剂黄146 、 二甲基亚砜 、 对苯醌 作用下， 反应 15.0h， 以9%的产率得到10-(3,5-dimethoxyphenyl)benzo[h]quinoline
  参考文献：
  名称：

  Controlling Site Selectivity in Pd-Catalyzed Oxidative Cross-Coupling Reactions

  摘要：

  This paper presents a detailed investigation of the factors controlling site selectivity in the Pd-mediated oxidative coupling of 1,3-disubstituted and 1,2,3-trisubstituted arenes (aryl -H) with cyclometalating substrates (L similar to C-H). The influence of both the concentration and the steric/electronic properties of the quinone promoter are studied in detail. In addition, the effect of steric/electronic modulation of the carboxylate ligand is discussed. Finally, we demonstrate that substitution of the carboxylate for a carbonate X-type ligand leads to a complete reversal in site selectivity for many arene substrates. The origins of these trends in site selectivity are discussed in the context of the mechanism of Pd-catalyzed oxidative cross-coupling.

  DOI：

  10.1021/ja1097918

文献信息

• On the role of anionic ligands in the site-selectivity of oxidative C–H functionalization reactions of arenes
  作者：Italo A. Sanhueza、Anna M. Wagner、Melanie S. Sanford、Franziska Schoenebeck

  DOI：10.1039/c3sc00017f

  日期：——

  The replacement of an acetate ligand for carbonate leads to a reversal in site-selectivity in the Pd-mediated C–H oxidative coupling of benzo[h]quinoline with 1,3-dimethoxybenzene. This report describes Density Functional Theory studies designed to elucidate the origin of this selectivity change. These studies focused on two key mechanistic steps: C–H activation and C–C bond-forming reductive elimination. We considered monometallic and bimetallic reaction pathways for acetate and carbonate conditions. The favored C–H activation pathway proceeds via a concerted metalation deprotonation (CMD) mechanism, independent of the nature of anionic ligand (acetate versus carbonate). The predicted selectivity is ortho/para for the C–H activation for both the acetate and carbonate-ligated Pd complexes. Further, we determined that the reductive elimination step is greatly facilitated by the coordination of benzoquinone (by ΔΔG‡ ∼ 20 kcal mol−1) and is predicted to be meta–meta selective with both anionic ligands. Overall, the DFT studies indicate that the anionic ligand does not induce a mechanism change at the elementary steps, and the predicted selectivity at all steps is equivalent for carbonate and acetate, no matter whether a dinuclear or mononuclear pathway is considered. These studies lead us to propose that the role of the anionic ligand is to control which step of the mechanism is overall selectivity-determining. This proposal has been tested experimentally using appropriately designed experiments. Notably, the insoluble base MgO as an acid trap under acetate conditions (with the aim of making the C–H insertion step less reversible), gave rise to predominant ortho/para selectivity in the presence of acetate, in analogy to the results previously seen under carbonate conditions.

  在钯介导的 1,3-二甲氧基苯与苯并[h]喹啉的 CâH 氧化偶联反应中，用碳酸盐取代醋酸盐配体会导致位点选择性的逆转。本报告介绍了旨在阐明这种选择性变化根源的密度泛函理论研究。这些研究侧重于两个关键的机理步骤：CâH 活化和 CâC 成键还原消除。我们考虑了醋酸盐和碳酸盐条件下的单金属和双金属反应途径。受青睐的 CâH 活化途径是通过协同金属化去质子化（CMD）机制进行的，与阴离子配体的性质（醋酸盐还是碳酸盐）无关。对于醋酸盐和碳酸盐配位的钯复合物，预测的 CâH 活化选择性为正/副选择性。此外，我们还确定，苯醌的配位（δGâ¡ â¼ 20 kcal molâ1）极大地促进了还原消除步骤，并预测这两种阴离子配体都具有元选择性。总体而言，DFT 研究表明，阴离子配体不会引起基本步骤的机理变化，而且无论考虑双核还是单核途径，碳酸酯和醋酸酯在所有步骤的预测选择性都是相同的。这些研究使我们提出，阴离子配体的作用是控制机理中哪一步对总体选择性起决定作用。我们通过适当设计的实验对这一观点进行了验证。值得注意的是，在醋酸盐条件下，将不溶性碱 MgO 作为酸阱（目的是降低 CâH 插入步骤的可逆性），在醋酸盐存在的情况下产生了主要的正/副选择性，这与之前在碳酸盐条件下看到的结果类似。