Results 11 to 20 of about 2,992 (134)
A Riboflavin-Derived Flavinium Salt Mediates Chemoselective Methylation Reactions. [PDF]
ChemistryA two‐component methylation protocol was developed, where the active flavin mediator can be recycled in a single step. Crystallographic data and NMR spectroscopy support the mechanistic proposal, while chemoselective methylation was observed for a broad range of biologically relevant substrates. ABSTRACT Selective methylation is among the most relevant
Langschwager T +3 more
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Molecules, 2021 Multiple zigzag chains Zm,n of length n and width m constitute an important class of regular graphene flakes of rectangular shape. The physical and chemical properties of these basic pericondensed benzenoids can be related to their various topological ...
Henryk A. Witek
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A wave-mechanical treatment of the Mills-Nixon effect [PDF]
, 1935 The Mills-Nixon effect has been examined by a very simple wave-mechanical treatment. This has led to the conclusion that the effect of saturated side rings upon the ratio of the coefficients of the wave-functions of the two Kekulé structures is ...
Pauling, L., Sutton, L. E.
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The electronic structure of benzene from a tiling of the correlated 126-dimensional wavefunction
Nature Communications, 2020 The electronic structure of benzene has been a test bed for competing theories along the years. Here the authors show via quantum chemistry calculations that the wavefunction of benzene can be partitioned into tiles which show that the two electron spins
Yu Liu +3 more
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Perimeter ring currents in benzenoids from Pauling bond orders [PDF]
, 2016 It is shown that the ring currents in perimeter hexagonal rings of Kekulean benzenoids, as estimated within the Randić conjugated-circuit model, can be calculated directly without tedious pairwise comparison of Kekulé structures or Kekulé counting for ...
Bird, W.H. +3 more
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Observation of nonlinear disclination states
Light: Science & Applications, 2023 Introduction of controllable deformations into periodic materials that lead to disclinations in their structure opens novel routes for construction of higher-order topological insulators hosting topological states at disclinations.
Boquan Ren +12 more
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Merging Pyrrole with Boron into Versatile Di(2-pyrryl)borane Building Blocks: π-Extension, Polymerization, and Coordination. [PDF]
Angew Chem Int Ed EnglThe synthesis of di(2‐pyrryl)boranes, including the previously elusive unprotected N–H derivative, has been achieved that serve as versatile building blocks for π‐extended tetrahetarene boranes, a poly(dipyrrole borane), and a zirconium(IV) complex. The new π‐conjugated boranes are efficient blue‐light emitters, due to a twisted intramolecular charge ...
Göbel D +6 more
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, 2018 Creativity has often been declared, especially by philosophers, as the last frontier of science. The assumption is that it will defy explanation forever.
Kronfeldner, Maria
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A simple mathematical model for the effect of benzoannelation on cyclic conjugation [PDF]
, 2011 In a series of earlier studies, it was established that benzoannelation in the angular (resp. linear) position relative to a ring R of a polycyclic conjugated π-electron system, increases (resp.
Balaban Aexanru T., Gutman Ivan
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Thiophene Derivatives as Versatile Precursors for (Hetero)Arene and Natural Product Synthesis. [PDF]
Angew Chem Int Ed EnglHidden but Powerful: Thiophenes and their saturated analogues have been demonstrated to be versatile C4‐building blocks that can be rapidly applied to natural product synthesis and the construction of functionalized (hetero)arenes. This minireview aims to provide a concise overview of the strategies and implementations of these sulfur‐containing ...
Keimer A, Haut FL.
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