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Beibei Li Zhanfeng Ju Mi Zhou Kongzhao Su Daqiang Yuan 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(23):7769-7773
The exploitation of new and active earth‐abundant metal catalysts is critical for sustainable chemical production. Herein, we demonstrate the design of highly efficient, robust, and reusable ZnII‐bipyridine‐based metal–organic framework (MOF) catalysts for the intramolecular hydroamination of o‐alkynylanilines to indoles. Under similar conditions homogeneous catalytic systems mainly provide hydrolysate. Our results prove that MOFs support unique internal environments that can affect the direction of chemical reactions. The ZnII‐catalyzed hydroamination reaction can be conducted without additional ligands, base, or acid, and is thus a very clean reaction system with regard to its environmental impact. 相似文献
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《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(6):1636-1640
A unique Ir complex (tBuNCCP)Ir with the pyridine–phosphine pincer as the sole ligand, featuring a dual agostic interaction between the Ir and two σ C−H bonds from a t Bu substituent, has been prepared. This complex exhibits exceptionally high activity and excellent regio‐ and stereoselectivity for monoisomerization of 1‐alkenes to trans ‐2‐alkenes with wide functional‐group tolerance. Reactions can be performed in neat reactant on a more than 100 gram scale using 0.005 mol % catalyst loadings with turnover numbers up to 19000. 相似文献
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《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(32):9689-9693
The aerobic oxidative cleavage of 1,2‐diols using a heterogeneous catalyst only based on earth‐abundant metals manganese and sodium is reported for the first time. This reusable catalyst cleaves a variety of substrates into aldehydes or ketones with high selectivity. The reaction requires small catalytic loadings and is performed under mild conditions using ambient pressure O2 or air as the oxidant while producing water as the only by‐product. Mechanistic investigations reveal a monodentate, two‐electron oxidative fragmentation process involving a MnIV species. The eco‐friendly, innocuous catalyst is compatible with a wide range of functional groups and conditions, making it highly competitive with classical reagents, such as periodic acid or lead tetraacetate, as a preferred method for activated 1,2‐diols. 相似文献