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71.
The nickel‐catalyzed amination of aryl chlorides to form primary arylamines occurs with ammonia or ammonium sulfate and a well‐defined single‐component nickel(0) precatalyst containing a Josiphos ligand and an η2‐bound benzonitrile ligand. This system also catalyzes the coupling of aryl chlorides with gaseous amines in the form of their hydrochloride salts.  相似文献   
72.
A single‐component ambiphilic system capable of the cooperative activation of protic, hydridic and apolar H? X bonds across a Group 13 metal/activated β‐diketiminato (Nacnac) ligand framework is reported. The hydride complex derived from the activation of H2 is shown to be a competent catalyst for the highly selective reduction of CO2 to a methanol derivative. To our knowledge, this process represents the first example of a reduction process of this type catalyzed by a molecular gallium complex.  相似文献   
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An olefin‐directed palladium‐catalyzed oxidative regio‐ and stereoselective arylation of allenes to afford 1,3,6‐trienes has been established. A number of functionalized allenes, including 2,3‐ and 3,4‐dienoates and 3,4‐dienol derivatives, have been investigated and found to undergo the olefin‐directed allene arylation. The olefin moiety has been proven to be a crucial element for the arylating transformation.  相似文献   
76.
Control of boronic acid speciation is presented as a strategy to achieve nucleophile chemoselectivity in the Suzuki–Miyaura reaction. Combined with simultaneous control of oxidative addition and transmetalation, this enables chemoselective formation of two C? C bonds in a single operation, providing a method for the rapid preparation of highly functionalized carbogenic frameworks.  相似文献   
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Metagenomic studies suggest that only a small fraction of the viruses that exist in nature have been identified and studied. Characterization of unknown viral genomes is hindered by the many genomes populating any virus sample. A new method is reported that integrates drop‐based microfluidics and computational analysis to enable the purification of any single viral species from a complex mixed virus sample and the retrieval of complete genome sequences. By using this platform, the genome sequence of a 5243 bp dsDNA virus that was spiked into wastewater was retrieved with greater than 96 % sequence coverage and more than 99.8 % sequence identity. This method holds great potential for virus discovery since it allows enrichment and sequencing of previously undescribed viruses as well as known viruses.  相似文献   
79.
Herein, we report a way to achieve abrupt high‐spin to low‐spin transition with controllable transition temperature and hysteresis width, relying not on solid‐state cooperative interactions, but utilizing coherency between phase and spin transitions in neutral FeII meltable complexes.  相似文献   
80.
The Group 18 elements (noble gases) were the last ones in the periodic system to have not been encountered in perovskite structures. We herein report the synthesis of a new group of double perovskites KM(XeNaO6) (M=Ca, Sr, Ba) containing framework‐forming xenon. The structures of the new compounds, like other double perovskites, are built up of the alternating sequence of corner‐sharing (XeO6) and (NaO6) octahedra arranged in a three‐dimensional rocksalt order. The fact that xenon can be incorporated into the perovskite structure provides new insights into the problem of Xe depletion in the atmosphere. Since octahedrally coordinated XeVIII and SiIV exhibit close values of ionic radii (0.48 and 0.40 Å, respectively), one could assume that XeVIII can be incorporated into hyperbaric frameworks such as MgSiO3 perovskite. The ability of Xe to form stable inorganic frameworks can further extend the rich and still enigmatic chemistry of this noble gas.  相似文献   
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