Daniel Stern  Nils Finkelmeier  Kathrin Meindl  Julian Henn  Dietmar Stalke 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2010,122(38):7021-7024

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Fritz Stern 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2012,124(1):50-58

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Dr. Nema Hafezi  Dr. James M. Holcroft  Dr. Karel J. Hartlieb  Edward J. Dale  Dr. Nicolaas A. Vermeulen  Charlotte L. Stern  Dr. Amy A. Sarjeant  Prof. J. Fraser Stoddart 《Angewandte Chemie (International ed. in English)》2015,54(2):456-461

We report the template‐directed synthesis of BlueCage⁶⁺, a macrobicyclic cyclophane composed of six pyridinium rings fused with two central triazines and bridged by three paraxylylene units. These moieties endow the cage with a remarkably electron‐poor cavity, which makes it a powerful receptor for polycyclic aromatic hydrocarbons (PAHs). Upon forming a 1:1 complex with pyrene in acetonitrile, however, BlueCage?6 PF₆ exhibits a lower association constant K_a than its progenitor ExCage?6 PF₆. A close inspection reveals that the six PF₆^? counterions of BlueCage⁶⁺ occupy the cavity in a fleeting manner as a consequence of anion–π interactions and, as a result, compete with the PAH guests. This conclusion is supported by a one order of magnitude increase in the K_a value for pyrene in BlueCage⁶⁺ when the PF₆^? counterions are replaced by much bulkier anions. The presence of anion–π interactions is supported by X‐ray crystallography, and confirms the presence of a PF₆^? counterion inside its cavity.  相似文献   

    

Stern F 《Angewandte Chemie (International ed. in English)》2012,51(1):50-56

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John W. Sibert  Steven J. Lange  Charlotte L. Stern  A. G. M. Barrett  Brian M. Hoffman 《Angewandte Chemie (International ed. in English)》1995,34(18):2020-2022

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Nicholas Prokopuk  Charles&#x;S. Weinert  David&#x;P. Siska  Charlotte&#x;L. Stern  Duward&#x;F. Shriver 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2000,112(18):3450-3453

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Meisa&#x;S. Khoshbin  Maxim&#x;V. Ovchinnikov  Khalid&#x;S. Salaita  Chad&#x;A. Mirkin  Charlotte&#x;L. Stern  Lev&#x;N. Zakharov  Arnold&#x;L. Rheingold 《化学:亚洲杂志》2006,1(5):686-692

Pyromellitic diimide and naphthalene diimide moieties were incorporated into hemilabile phosphanylalkyl thioether ligands. These ligands reacted with [Cu(CH₃CN)₄]PF₆ and [Rh(NBD)Cl]₂ (NBD=norbornadiene) by the weak‐link approach to form condensed intermediates. Upon reaction of each diimide ligand with these transition‐metal precursors, the two diimide units became cofacially aligned within a supramolecular macrocyclic architecture. The introduction of ancillary ligands to each of these condensed intermediates caused the weak thioether–metal bonds to break, thus generating a large macrocycle in which the distance between diimide units is significantly larger than for the condensed intermediates. The two Rh^I cationic condensed intermediates were characterized by single‐crystal X‐ray diffraction studies, and the electrochemical activity of these macrocycles was demonstrated with the naphthalene diimide–Cu^I macrocycles.  相似文献   

    

Izumi HK  Kirsch JE  Stern CL  Poeppelmeier KR 《Inorganic chemistry》2005,44(4):884-895

Out-of-center \"primary\" electronic distortions are inherent to the oxide fluoride anions of the early d0 transition metals. In the [NbOF5]2- anion, the Nb5+ moves from the center of the octahedron toward the oxide ligand to form a short Nb=O bond and long trans Nb-F bond. The combined results of single-crystal X-ray diffraction and electronic structure calculations indicate that the primary distortion of the [NbOF5]2- anion is affected by the coordination environment that is created by the three-dimensional extended structure. The formation of bonds between an M(L)4(2+) (M = Cd2+, Cu2+; L = 3-aminopyridine, 4-aminopyridine) cation and the oxide and/or trans-fluoride ligands of the [NbOF5]2- anion weakens the pi component of the Nb=O bond. At the same time, hydrogen bond interactions between the equatorial fluorides and the aminopyridine groups both lengthen the equatorial Nb-F bonds and can further reduce the symmetry of the [NbOF5]2- anion. These combined three-dimensional bond network interactions that serve to lengthen the Nb=O bond and thereby decrease the primary distortion of the [NbOF5]2- anion are illustrated in the structures of three new niobium oxide fluoride phases, [4-apyH]2[Cu(4-apy)4(NbOF5)2] (4-apy = 4-aminopyridine), Cd(3-apy)4NbOF5 (3-apy = 3-aminopyridine), and Cu(3-apy)4NbOF5, that were synthesized and characterized using X-ray diffraction. Crystal data for [4-apyH]2[Cu(4-apy)4(NbOF5)2]: tetragonal, space group /4(1)/ acd (No. 142), with a = 20.8745(8) A, c = 17.2929(9) A, and Z= 8. Cd(3-apy)4NbOF5: tetragonal, space group P4(3) (No. 78), with a = 8.4034(4) A, c = 34.933(3) A, and Z = 4. Cu(3-apy)4NbOF5: monoclinic, space group P2(1)/n (No. 14), with a = 8.822(1) A, b = 16.385(3) A, c = 8.902(1) A, beta = 109.270(3) degrees, and Z = 2.  相似文献   

Aërogengas     

A. Stern 《Analytical and bioanalytical chemistry》1905,44(6-7):416-416

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Calorimetrie     

J. Lamort  P. Rothemund  H. Beyer  A. Stern  G. Klebs  M. M. Popoff  P. K. Schirokich  E. W. Washburn  L. G. Carpenter  T. F. Harle  A. L. Norton  H. Esser  W. Grass  F. Barry  A. K. Smith  I. W. Krotow  R. S. Jessup 《Analytical and bioanalytical chemistry》1934,98(7-8):268-273

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