Hydrogen Bonding to a Dinitrogen Complex at Room Temperature: Impacts on N<sub>2</sub> Activation
作者:James P. Shanahan、Nathaniel K. Szymczak
DOI:10.1021/jacs.9b02288
日期:2019.5.29
computational analysis of the effects of hydrogenbonding to a metal dinitrogen complex. A series of H-bond donors over a wide p Ka range (Δ 20) interact with the nitrogen unit of a ReI-(N2) complex at room temperature. Analysis by 15N NMR, IR spectroscopy, association equilibria, and DFT studies indicates that the H-bonding interaction polarizes and weakens the N-N bond. These results provide insight into
我们报告了氢键对金属二氮配合物的影响的实验和计算分析。一系列宽 p Ka 范围 (Δ 20) 上的氢键供体在室温下与 ReI-(N2) 复合物的氮单元相互作用。通过 15N NMR、IR 光谱、缔合平衡和 DFT 研究的分析表明,氢键相互作用极化并削弱了 NN 键。这些结果提供了深入了解二级球体残基在固氮酶中的作用。
Scope and Mechanisms of Frustrated Lewis Pair Catalyzed Hydrogenation Reactions of Electron‐Deficient CC Double Bonds
hydrogenation reactions catalyzed by frustrated Lewis pairs, were synthesized in high yield under mild conditions from triaryl boranes, ammonium or phosphonium halides, and triethylsilane. The kinetics and mechanisms of the reactions of these hydridoborate salts with benzhydrylium ions, iminium ions, quinone methides, and Michael acceptors were investigated, and their nucleophilicity was determined and compared
Electrophilic Phosphonium Cation‐Mediated Phosphane Oxide Reduction Using Oxalyl Chloride and Hydrogen
作者:Arne J. Stepen、Markus Bursch、Stefan Grimme、Douglas W. Stephan、Jan Paradies
DOI:10.1002/anie.201809275
日期:2018.11.12
The metal‐free reduction of phosphaneoxides with molecular hydrogen (H2) using oxalyl chloride as activating agent was achieved. Quantum‐mechanical investigations support the heterolytic splitting of H2 by the in situ formed electrophilic phosphonium cation (EPC) and phosphaneoxide and subsequent barrierless conversion to the phosphane and HCl. The reaction can also be catalyzed by the frustrated
使用草酰氯作为活化剂,实现了以分子氢(H 2)对金属氧化物氧化物的无金属还原。量子力学研究支持通过原位形成的亲电phospho阳离子(EPC)和氧化膦进行H 2的杂化裂解,以及随后的无阻转化为膦和HCl。该反应还可以通过由B(2,6-F 2 C 6 H 3)3和2,6-二甲基吡啶或氧化膦作为Lewis碱组成的沮丧Lewis对(FLP)催化。三芳基和二芳基氧化膦证明了这种新颖的还原方法,提供了以良好至极佳收率(51%至93%)的膦原子。
Tris(2,4,6-trifluorophenyl)borane: An Efficient Hydroboration Catalyst
作者:James R. Lawson、Lewis C. Wilkins、Rebecca L. Melen
DOI:10.1002/chem.201703109
日期:2017.8.16
The metal‐free catalyst tris(2,4,6‐trifluorophenyl)borane has demonstrated its extensive applications in the 1,2‐hydroboration of numerous unsaturated reagents, namely alkynes, aldehydes and imines, consisting of a wide array of electron‐withdrawing and donating functionalities. A range of over 50 borylated products are reported, with many reactions proceeding with low catalyst loading under ambient
Metal-Free Iodoperfluoroalkylation: Photocatalysis versus Frustrated Lewis Pair Catalysis
作者:Constantin Czekelius、Lucas Helmecke、Michael Spittler、Bernd M. Schmidt
DOI:10.1055/s-0040-1707232
日期:2021.1
Professor Rolf Huisgen Abstract A comparison of two catalytic, metal-free iodoperfluoroalkylation protocols is presented. FrustratedLewispairs [ t Bu3P/B(C6F5)3] or phosphines/phosphites under visible light irradiation efficiently mediate the functionalization of non-activated alkenes and alkynes. A comprehensive account of the corresponding substrate scopes as well as insights into the mechanistic details
纪念Rolf Huisgen教授 抽象 比较了两种催化的,无金属的碘代氟烷基化方案。沮丧的路易斯对[ t Bu 3 P / B(C 6 F 5)3 ]或膦/亚磷酸盐在可见光辐射下有效地介导了未活化的烯烃和炔烃的官能化。提供了对相应底物范围的全面介绍,以及对两种反应途径的机理细节的见解。