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M. Sc. Jannik Gilmer M. Sc. Hendrik Budy Dr. Thomas Kaese Dr. Michael Bolte Dr. Hans-Wolfram Lerner Prof. Dr. Matthias Wagner 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(14):5670-5674
Double reduction of the THF adduct of 9H-9-borafluorene ( 1 ⋅THF) with excess alkali metal affords the dianion salts M2[ 1 ] in essentially quantitative yields (M=Li–K). Even though the added charge is stabilized through π delocalization, [ 1 ]2− acts as a formal boron nucleophile toward organoboron ( 1 ⋅THF) and tetrel halide electrophiles (MeCl, Et3SiCl, Me3SnCl) to form B−B/C/Si/Sn bonds. The substrate dependence of open-shell versus closed-shell pathways has been investigated. 相似文献
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In this paper, we prove a local limit theorem for the distribution of the number of triangles in the Erdos‐Rényi random graph G(n, p), where is a fixed constant. Our proof is based on bounding the characteristic function of the number of triangles, and uses several different conditioning arguments for handling different ranges of t. © 2016 Wiley Periodicals, Inc. Random Struct. Alg., 48, 732–750, 2016 相似文献
166.
N-benzyldiphenylphosphinamides are deprotonated at the NCalpha position diastereospecifically upon treatment with t-BuLi in diethyl ether at low temperature. The reaction of the anions with alkyl, acyl, and tin halides, aliphatic and aromatic aldehydes, and Michael acceptors allowed installation of a variety of functional groups into the benzylic arm in excellent yields. Cleavage of the P-N linkage affords 1,2-amino alcohols and alpha-, beta-, and gamma-amino acids. 相似文献
167.
M Morón C Burgos J Alvarez-Builla A Salgado ME Mosquera JJ Vaquero 《Chemical communications (Cambridge, England)》2012,48(73):9171-9173
The reaction of bromo substituted pyrido[3',2':4,5]pyrrolo-[1,2-c]pyrimidine and pyrimido[1,6-a]indole methyl carboxylates with primary amines is described. The expected amide formation occurs but it is followed by an unexpected cascade process involving attack of the amine to the pyrimidine ring, opening of the pyrimidine ring, loss of the bromine substituent and competitive cyclizations to afford unusual imidazolidene substituted indoles and azaindoles. 相似文献
168.
M. L. Izquierdo E. Glvez C. Burgos F. Florencio 《Journal of heterocyclic chemistry》1988,25(2):419-423
A series of N-β(γ)-acyloxyalkylnortropinones have been synthesized and studied by 1H and 13C nmr spectroscopy, and the crystal structure of N-[γ-(p-chlorophenylcarbonyloxy)propyl]nortropinone 4 has been determined by X-ray diffraction. The compounds studied display in deuteriochloroform solution the same preferred conformation. The pyrrolidine and piperidone rings adopt a flattened N-8 envelope and distorted chair conformation, puckered at N-8 and flattened at C-3 respectively, with the N-substituent in axial position with respect to the piperidone ring. These results are in close agreement with that found for compound 4 in the crystalline state. 相似文献
169.
Cover Picture: Peptoid‐Ligated Pentadecanuclear Yttrium and Dysprosium Hydroxy Clusters (Chem. Eur. J. 7/2015) 下载免费PDF全文
Dr. Dominique T. Thielemann Anna T. Wagner Dr. Yanhua Lan Dr. Pascual Oña‐Burgos Prof. Dr. Ignacio Fernández Prof. Dr. Esther S. Rösch Dr. Dominik K. Kölmel Prof. Dr. Annie K. Powell Prof. Dr. Stefan Bräse Prof. Dr. Peter W. Roesky 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(7):2709-2709
170.
Degradation of poly(vinyl chloride) plasticized with non-phthalate plasticizers under sterilization conditions 总被引:1,自引:0,他引:1
Plasticized PVC formulations have traditionally been used in the production of medical devices, such as tubes and bags for plasma or blood because of their good performance in mechanical and thermal properties as well as their low cost. Clinical practice, in particular re-use after sterilization, can damage and promote degradation of these materials with the risk of release of polymer additives into physiological fluids and consequently risks to patient's health. Formulations with commercial plasticizers, alternative to traditional phthalates (citrate and carboxylate compounds) have been proposed in this work and their behaviour after repeated sterilization has been evaluated. Structural, mechanical, thermal and surface properties have been tested and no significant degradation was observed. No apparent risk of massive damage to plasticized PVC could be considered after repeated sterilization. 相似文献