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171.
Palladium‐Catalyzed Construction of Amidines from Arylboronic Acids under Oxidative Conditions 下载免费PDF全文
Fengxiang Zhu Yahui Li Zechao Wang Prof. Dr. Romano V. A. Orru Prof. Dr. Bert U. W. Maes Prof. Dr. Xiao‐Feng Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(23):7743-7746
A valuable palladium‐catalyzed three‐component coupling reaction for the synthesis of amidines has been developed. Using arylboronic acids, isocyanides, and anilines as the reactants under oxidative conditions, various amidines were isolated in good yields with good functional group tolerances. 相似文献
172.
Condensation of 2-nitrobenzenesulfonyl chloride with 2-ethoxycarbonyl-1H-pyrrole in the presence of potassium tert-butoxide and 18-crown-6 furnished 2-ethoxycarbonyl-1-(2-nitrobenzenesulfonyl)-1H-pyrrole. Reduction of nitro group to amino and subsequent cyclization by heating the aminoester in the presence of 2-hydroxypyridine as a bifuctional catalyst led to 11-oxo(10H)-pyrrolo[1,2-b] [1,2,5]benzothiadiazepine 5,5-dioxide. Treatment of the latter compound with di-4-morpholinylphosphinic chloride gave the corresponding phosphinyloxyimine, which on reacting with formylhydrazine underwent intramolecular cyclization to afford the title tetracyclic ring. 相似文献
173.
ABSTRACTClusters of planar-aligned short-pitch cholesteric liquid crystal spheres generate dynamic colourful patterns due to multiple selective reflections from the radially oriented cholesteric helices in neighbour shells at varying distances. These photonic communication patterns were widely investigated for the cases of both droplets and shells, demonstrating not only intriguing optical phenomena but also potential for applications as new optical elements for photonics, sensing or security pattern generation. However, the optics of these clusters is truly complex and until now only the strongest and most fundamental reflections have been analysed and explained. In this report, we elucidate the origin of a number of more subtle reflections and we explain the extension in space of various spots as well as their internal colour variations. 相似文献
174.
Abstract This paper focuses on the composting behavior of Mater-Bi Z grades for filming and on their in-use behavior, mainly as composting bags for the collection of organic waste. The compostability of Mater-Bi Z grades was demonstrated by means of a three-step test by following the approach of different international committees working on this matter comprising lab tests (biodegradability tests such as ASTM D 5338, ASTM 5901, and terrestrial toxicity tests) and full-scale composting tests. In addition to their compostability, the in-use behavior was estimated by tests of separate collection of organic wastes in different municipalities (Furstenfeldbruck/Bavaria, Korneuburg/Austria) comparing paper bags with Mater-Bi bags. 相似文献
175.
Treatment of oximes and semicarbazones of saturated and α,β-unsaturated ketones and aldehydes with trimethylchlorosilane-dimethyl sulphoxide in dry acetonitrile affords the corresponding carbonyl compounds in excellent yields under mild conditions. 相似文献
176.
177.
Nadia Manzo Fabiana Pizzolongo Alessandra Aiello Raffaele Romano 《Natural product research》2019,33(13):1835-1841
Heat treatments can cause degradation in tomatoes of lycopene which has important antioxidant effects. No information about decimal reduction time (D100) of lycopene is available. D-value is the time required at a given temperature to reduce 90% of the molecule. This study for the first time determine the kinetic of lycopene thermal degradation. The content was measured at regular intervals of pasteurization using canned tomato paste to determinate D value. Microbiological analysis was carried out to verify product stability after packaging. Yeasts, molds and lactic acid bacteria were determined. The pasteurization time allowed to observe a loss of the red color. Lycopene content, after an increase at 8 min, decreased at 32 min of pasteurization. D100 value was calculated at 75 min; a diminution of 90% in lycopene content in the concentrated tomato paste was observed. Microbiological analysis confirmed the stability of products after 8 min of pasteurization. 相似文献
178.
The paper is concerned with the IBVP of the Navier–Stokes equations. The goal is to evaluate the possible gap between the energy equality and the energy inequality deduced for a weak solution. This kind of analysis is new and the result is a natural continuation and improvement of a result obtained by the same authors in Crispo et al. (Some new properties of a suitable weak solution to the Navier–Stokes equations. arXiv:1904.07641).
相似文献179.
Two novel tetracyclic derivatives, namely 5 and 8, have been synthesized by intramolecular cyclization of the 10-bromoacetyl-10,11-dihydro-11-ethoxycarbonylpyrrolo[1,2-b] [1,2,5]benzothiadiazepine 5,5-dioxide (3) and, respectively, the bis-methylamide of 11-carboxy-10,11-dihydropyrrolo[1,2-b] [1,2,5]benzothiadiazepine-11-acetic acid 5,5-dioxide (4). The last compound formed when treating with an excess of methylamine either the lactam 5 or the diethyl ester of 11-carboxy-10,11-dihydropyrrolo[1,2-b] [1,2,5]benzothiadiazepine-11-acetic acid 5,5-dioxide (7). An unambiguous synthesis of the diester 7 was achieved to confirm the chemical structure of derivatives 4 and 5. 相似文献
180.