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Iodine(III)‐Catalyzed Rearrangements of Imides: A Versatile Route to α,α‐Dialkylated α‐Hydroxy Carboxylamides 下载免费PDF全文
Anna Ulmer Dr. Maciej Stodulski Stefanie V. Kohlhepp Christoph Patzelt Dr. Alexander Pöthig Dr. Wolfgang Bettray Dr. Tanja Gulder 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(4):1444-1448
A tertiary hydroxy group α to a carboxyl moiety comprises a key structural motif in many bioactive substances. With the herein presented metal‐free rearrangement of imides triggered by hypervalent λ3‐iodane, an easy and selective way to gain access to such a compound class, namely α,α‐disubstituted‐α‐hydroxy carboxylamides, was established. Their additional methylene bromide side chain constitutes a useful handle for rapid diversification, as demonstrated by a series of further functionalizations. Moreover, the in situ formation of an iodine(III) species under the reaction conditions was proven. Our findings clearly corroborate that hypervalent λ3‐benziodoxolones are involved in these organocatalytic reactions. 相似文献
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Unexpected benzimidazole ring formation from a quinoneimide species in the presence of ammonium acetate as supporting electrolyte used in the coupling of electrochemistry with mass spectrometry 下载免费PDF全文
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Timm Bergholz Dr. Benjamin Oelkers Dr. Benedikt Huber Prof. Bernhard Roling Prof. Dr. Jörg Sundermeyer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(6):2613-2620
New salts based on imidazolium, pyrrolidinium, phosphonium, guanidinium, and ammonium cations together with the 5‐cyanotetrazolide anion [C2N5]? are reported. Depending on the nature of cation–anion interactions, characterized by XRD, the ionic liquids (ILs) have a low viscosity and are liquid at room temperature or have higher melting temperatures. Thermogravimetric analysis, cyclic voltammetry, viscosimetry, and impedance spectroscopy display a thermal stability up to 230 °C, an electrochemical window of 4.5 V, a viscosity of 25 mPa s at 20 °C, and an ionic conductivity of 5.4 mS cm?1 at 20 °C for the IL 1‐butyl‐1‐methylpyrrolidinium 5‐cyanotetrazolide [BMPyr][C2N5]. On the basis of these results, the synthesized compounds are promising electrolytes for lithium‐ion batteries. 相似文献
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Lubomír Havlk Jan Fbry Margarida Henriques Michal Duek 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(7):623-630
The title structures of KScS2 (potassium scandium sulfide), RbScS2 (rubidium scandium sulfide) and KLnS2 [Ln = Nd (potassium neodymium sufide), Sm (potassium samarium sulfide), Tb (potassium terbium sulfide), Dy (potassium dysprosium sulfide), Ho (potassium holmium sulfide), Er (potassium erbium sulfide), Tm (potassium thulium sulfide) and Yb (potassium ytterbium sulfide)] are either newly determined (KScS2, RbScS2 and KTbS2) or redetermined. All of them belong to the α‐NaFeO2 structure type in agreement with the ratio of the ionic radii r3+/r+. KScS2, the member of this structural family with the smallest trivalent cation, is an extreme representative of these structures with rare earth trivalent cations. The title structures are compared with isostructural alkali rare earth sulfides in plots showing the dependence of several relevant parameters on the trivalent cation crystal radius; the parameters thus compared are c, a and c/a, the thicknesses of the S—S layers which contain the respective constituent cations, the sulfur fractional coordinates z(S2−) and the bond‐valence sums. 相似文献
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Saleh Z. M. Nasser H. Özkol E. Günöven M. Abak K. Canli S. Bek A. Turan R. 《Journal of nanoparticle research》2015,17(10):1-12
Journal of Nanoparticle Research - Plasmonic interfaces consisting of silver nanoparticles of different sizes (50–100&;nbsp;nm) have been processed by the self-assembled dewetting... 相似文献