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101.
Observation of Spontaneous C=C Bond Breaking in the Reaction between Atomic Boron and Ethylene in Solid Neon 下载免费PDF全文
Jiwen Jian Dr. Hailu Lin Prof. Mingbiao Luo Dr. Mohua Chen Prof. Mingfei Zhou 《Angewandte Chemie (International ed. in English)》2016,55(29):8371-8374
A ground‐state boron atom inserts into the C=C bond of ethylene to spontaneously form the allene‐like compound H2CBCH2 on annealing in solid neon. This compound can further isomerize to the propyne‐like HCBCH3 isomer under UV light excitation. The observation of this unique spontaneous C=C bond insertion reaction is consistent with theoretical predictions that the reaction is thermodynamically exothermic and kinetically facile. This work demonstrates that the stronger C=C bond, rather than the less inert C?H bond, can be broken to form organoboron species from the reaction of a boron atom with ethylene even at cryogenic temperatures. 相似文献
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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. 相似文献
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Jessica Cid Dr. Jorge J. Carbó Dr. Elena Fernández 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(40):12794-12802
Most trivalent boron reagents are electrophiles owing to the vacancy for two electrons to fill the outer orbital of boron; however, interestingly, trivalent boron compounds can change their electrophilic character to a nucleophilic character by only changing the nature of the substituents on the boron atoms. With the help of computational tools, we have analyzed the structural‐ and electronic properties of boryl fragments that were either bonded to main‐group metals or coordinated to transition‐metals/rare‐earth‐metals and we have designed a map that might help to identify certain trends. This trend map will be useful for selecting an appropriate trivalent boron compound, depending on the sought reactivity. 相似文献
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The efficient 'on water' β‐borylation using bis(pinacolato)diboron agent was achieved with a newly developed catalytic system based on basic copper carbonate and various ligands. The catalytic system was used for β‐borylation of various Michael acceptors, alkenes and alkynes. The presented methodology was successfully applied to the novel synthesis of β‐alcohol type sitagliptin side chain precursor via water‐based highly enantioselective β‐borylation followed by an oxidation process. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献