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201.
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Emmanuelle Dubost Silvia Stiebing Thibault Ferrary Thomas Cailly Frédéric Fabis Valérie Collot 《Tetrahedron》2014
A set of variously substituted indazoles and hetero-aromatic derivatives were synthesized from o-halo-(het)arylaldehydes using a palladium catalyzed amination followed by cyclization. Starting from phenones, this process was extended to give 3-substituted indazoles. Moreover, N-1-substituted-indazoles can be reached by this strategy using an optional selective N-1-alkylation step during the process. This methodology offers a general and easy route for the synthesis of regioselectively substituted indazoles. 相似文献
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Christian Neis Thomas Kradolfer Kaspar Hegetschweiler 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(6):632-637
Single crystals of (1,3‐diamino‐5‐azaniumyl‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)(1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)lithium(I) diiodide dihydrate, [Li(C6H16N3O3)(C6H15N3O3)]I2·2H2O or [Li(Htaci)(taci)]I2·2H2O (taci is 1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol), (I), bis(1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)sodium(I) iodide, [Na(C6H15N3O3)2]I or [Na(taci)2]I, (II), and bis(1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)potassium(I) iodide, [K(C6H15N3O3)2]I or [K(taci)2]I, (III), were grown by diffusion of MeOH into aqueous solutions of the complexes. The structures of the Na and K complexes are isotypic. In all three complexes, the taci ligands adopt a chair conformation with axial hydroxy groups, and the metal cations exhibit exclusive O‐atom coordination. The six O atoms of the resulting MO6 unit define a centrosymmetric trigonal antiprism with approximate D3d symmetry. The interligand O...O distances increase significantly in the order Li < Na < K. The structure of (I) exhibits a complex three‐dimensional network of R—NH2—H...NH2—R, R—O—H...NH2—R and R—O—H...O(H)—H...NH2—R hydrogen bonds. The structures of the Na and K complexes consist of a stack of layers, in which each taci ligand is bonded to three neighbours via pairwise O—H...NH2 interactions between vicinal HO—CH—CH—NH2 groups. 相似文献
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Thomas Wick 《PAMM》2015,15(1):619-620
In this study, we consider phase-field-based fracture propagation in solid mechanics. The phase-field model is based on a thermodynamically-consistent version proposed by Miehe, Welschinger, Hofacker. The main focus is on goal-oriented functional evaluations using a partition-of-unity dual-weighted residual estimator for accurate measurement of, for example, point values, stresses, or crack opening displacements. Our developments are substantiated with a numerical test. (© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
209.
de Oliveira Thomas Rafael Tannous Katia de Lima Elisangela Cristina Trevisan 《Journal of Thermal Analysis and Calorimetry》2022,147(13):7431-7448
Journal of Thermal Analysis and Calorimetry - This work aims to investigate the thermal decomposition and reaction kinetics of the hybrid energy cane, as well as its thermochemical properties.... 相似文献
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Invited for this month′s cover picture is the group of Thomas Wirth at Cardiff University (UK). The cover picture shows two structures of triptycenes. In each of these molecules all three aromatic rings are different with the rigid structure of the molecules making them chiral. The two sp3-carbons shown in red and green are the stereocentres with defined configuration. These molecules contain the crucial iodine functionality which are utilised to generate hypervalent iodine(III)-catalysts in situ . The authors acknowledge Dr. Yu Wang for the creation of the cover image. Read the full text of their Research Article at 10.1002/open.202200145 . 相似文献