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《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(42):13302-13305
A highly practical and step‐economic α,β‐dehydrogenation of carboxylic acids via enediolates is reported through the use of allyl‐palladium catalysis. Dianions underwent smooth dehydrogenation when generated using Zn(TMP)2⋅2 LiCl as a base in the presence of excess ZnCl2, thus avoiding the typical decarboxylation pathway of these substrates. Direct access to 2‐enoic acids allows derivatization by numerous approaches. 相似文献
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Hikaru Yanai Takumi Suzuki Florian Kleemiss Haruhiko Fukaya Yasuo Dobashi Lorraine A. Malaspina Simon Grabowsky Takashi Matsumoto 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(26):8931-8936
1,1‐Diamino‐2,2‐bis(triflyl)ethylenes with both twisted and planar structures around the partial “C=C” bond were synthesised. Bonding properties in these compounds were analysed by an experimental approach using high‐resolution X‐ray diffraction data treated with X‐ray wavefunction refinement (XWR). In the twisted compound, a dominant contribution of the charge‐separated resonance structure was revealed. On the contrary, the nearly planar compound still showed π‐bonding character, however, with a considerable contribution of the charge‐separated resonance structure. 相似文献
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Rakesh Dontha Tian‐Cheng Zhu Yunjun Shen Michael Wrle Xin Hong Simon Duttwyler 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(52):19183-19189
The lithiacarborane [Li?CB11H11]? plays a central role in carborane chemistry, as it is a key intermediate to achieve the selective functionalization of the monocarba‐closo‐dodecaborate [CB11H12]? for applications in various fields. Also, it is an organometallic species of fundamental interest because it represents a 3D analogue of phenyllithium featuring an exo C?Li bond in addition to the delocalized negative endo charge of the spherical cluster. For the first time, the elusive and highly reactive endo/exo formal dianion [CB11H11]2? has been isolated as its lithiate as well as zincate in pure form and fully characterized. DFT calculations corroborate the experimental findings and underscore the remarkably high reactivity of the lithiacarborane. Subsequent derivatizations demonstrate the relevance of its initial clean formation. 相似文献