Catalytic Aerobic Oxidation of Alcohols by Copper Complexes Bearing Redox-Active Ligands with Tunable H-Bonding Groups
作者:Khashayar Rajabimoghadam、Yousef Darwish、Umyeena Bashir、Dylan Pitman、Sidney Eichelberger、Maxime A. Siegler、Marcel Swart、Isaac Garcia-Bosch
DOI:10.1021/jacs.8b08748
日期:2018.12.5
describe the structure, spectroscopy, and reactivity of a family of copper complexes bearing bidentate redox-active ligands that contain H-bonding donor groups. Single-crystal X-ray crystallography shows that these tetracoordinate complexes are stabilized by intramolecular H-bonding interactions between the two ligand scaffolds. Interestingly, the Cu complexes undergo multiple reversible oxidation-reduction
在这篇研究文章中,我们描述了带有双齿氧化还原活性配体的铜配合物家族的结构、光谱和反应性,这些配体含有氢键供体基团。单晶 X 射线晶体学表明,这些四配位配合物通过两个配体支架之间的分子内 H 键相互作用稳定。有趣的是,Cu 配合物经历了与金属离子(CuI、CuII、CuIII)和/或邻苯基二氨基配体(L2-、L•-、L)相关的多个可逆氧化还原过程。此外,一些 CuII 复合物在室温下催化醇类有氧氧化为醛类(或酮类)。我们广泛的机理分析表明,醇的脱氢是通过半乳糖氧化酶模型系统的一种不寻常的反应途径发生的,
Desymmetrisation of aromatic diamines and synthesis of non-symmetrical thiourea derivatives by click-mechanochemistry
作者:Vjekoslav Štrukil、Davor Margetić、Marina D. Igrc、Mirjana Eckert-Maksić、Tomislav Friščić
DOI:10.1039/c2cc34013e
日期:——
ortho- and para-Phenylenediamines were desymmetrised and quantitatively transformed into mono- and bis-(thio)ureas or mixed thiourea–ureas through a one-pot mechanochemical click reaction sequence; mechanochemical desymmetrisation proceeds quantitatively without excess reagents and allows the controlled extension of a molecular structure by combining normally competing reactions.
Carboxylate complexation by 1,1′-(1,2-phenylene)bis(3-phenylurea) in solution and the solid state
作者:Simon J. Brooks、Philip A. Gale、Mark E. Light
DOI:10.1039/b508144k
日期:——
A simple bis-urea containing anion receptor, synthesised from ortho-phenylenediamine, has been shown to have excellent selectivity for carboxylates in solution, with a crystal structure elucidation of the benzoate complex showing four hydrogen bonds between the receptor and anion in the solid state.
Two-Electron Redox Tuning of Cyclopentadienyl Cobalt Complexes Enabled by the Phenylenediamide Ligand
作者:Minzhu Zou、Thomas J. Emge、Kate M. Waldie
DOI:10.1021/acs.inorgchem.3c01283
日期:2023.7.3
transition-metal complexes has important implications for homogeneous catalysis using earth-abundant metals. Here, we report a family of cobalt–phenylenediamide complexes that undergo reversible 2e– oxidation regardless of the ligand substituents, enabling unprecedented multielectron redox tuning over 0.5 V and, in each case, affording the dicationic Co(III)-benzoquinonediimine species. The neutral complexes are
在第一行过渡金属配合物中实现多电子活性对于使用地球丰富的金属进行均相催化具有重要意义。在这里,我们报道了一系列钴-苯二酰胺配合物,无论配体取代基如何,它们都会经历可逆的 2e 氧化,从而实现前所未有的多电子氧化还原调谐超过 0.5 V,并且在每种情况下都提供双阳离子 Co(III)-苯醌二亚胺物种。中性配合物最好被描述为金属环中具有π键的离域系统,与密度泛函理论(DFT)计算预测的闭壳单线态基态一致。我们的 DFT 结果还预测了2e氧化的 ECE 途径(ECE = 电化学步骤、化学步骤、电化学步骤),其中第一个 1e–该步骤涉及氧化还原诱导的电子转移以产生 Co(II) 中间体。在这种状态下,金属环键合的破坏可以通过加成配体的缔合来改变配位几何形状,这对于实现电势反转至关重要。苯二酰胺配体的电子特性决定第二个电子是否从配体或金属中丢失,为第一行系统中可调谐 2e 行为提供了一个显着的例子。