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Eunji Lee Jung‐Keun Kim Myongsoo Lee Prof. 《Angewandte Chemie (International ed. in English)》2009,48(20):3657-3660
Deep‐water scrolls: It is demonstrated that amphiphilic rods containing lateral flexible chains self‐assemble into two‐dimensional sheets in aqueous solution (see picture). Remarkably, the sheets roll up reversibly into tubular scrolls upon heating, as confirmed by cryo‐transmission electron microscopy and fluorescence microscopy.
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Dong‐Je Hong Eunji Lee Haemi Jeong Jeong‐kyu Lee Wang‐Cheol Zin Trung Dac Nguyen Sharon C. Glotzer Myongsoo Lee Prof. 《Angewandte Chemie (International ed. in English)》2009,48(9):1664-1668
On a roll : Attachment of flexible coils to the middle of a rigid rod generates T‐shaped rod–coil molecules that self‐assemble into layers that roll up to form filled cylindrical and hollow tubular scrolls, depending on the coil length, in the solid state (see picture); the rods are arranged parallel to the layer plane.
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Bingjun Xu Xiaoying Liu Jan Haubrich Dr. Robert J. Madix Prof. Cynthia M. Friend Prof. 《Angewandte Chemie (International ed. in English)》2009,48(23):4206-4209
The Midas touch : The low‐temperature transformation of methanol to methyl formate, formaldehyde, and formic acid is promoted by atomic oxygen adsorbed on metallic gold (see picture). The reactions occur with O‐containing Au nanoparticles formed on Au(111) upon oxidation with ozone at 200 K; the facile esterification to methyl formate occurs well below room temperature.
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Jakob T. Nielsen Dr. Morten Bjerring Dr. Martin D. Jeppesen Ronnie O. Pedersen Jan M. Pedersen Dr. Kim L. Hein Thomas Vosegaard Dr. Troels Skrydstrup Prof. Daniel E. Otzen Prof. Niels C. Nielsen Prof. 《Angewandte Chemie (International ed. in English)》2009,48(12):2118-2121
The fibril structure formed by the amyloidogenic fragment SNNFGAILSS of the human islet amyloid polypeptide (hIAPP) is determined with 0.52 Å resolution. Symmetry information contained in the easily obtainable resonance assignments from solid‐state NMR spectra (see picture), along with long‐range constraints, can be applied to uniquely identify the supramolecular organization of fibrils.
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Jing Tan Xianxiu Xu Dr. Lingjuan Zhang Yifei Li Qun Liu Prof. 《Angewandte Chemie (International ed. in English)》2009,48(16):2868-2872
Up to four adjacent stereocenters can be formed stereoselectively in the construction of a pyrrolizidine unit through a novel organocatalytic reaction that involves treatment of various dienones with ethyl isocyanoacetate (see scheme; DBU=1,8‐diazabicyclo[5.4.0]undec‐7‐ene). Mechanisms for this atom‐economic, one‐pot synthesis have been proposed.
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Keunho Kim Jin Kun Cha Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(29):5334-5336
A stereoselective synthesis of cyathin A3 and cyathin B2 has been achieved by a Prins‐type reaction of a cycloalkenyl cyclopropanol. Particularly noteworthy is the use of a spirocyclobutanone moiety as a convenient scaffold for an efficient ring‐closing metathesis to stereoselectively construct a suitably functionalized seven‐membered ring (see scheme).
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Jung Hee Yoon Dae Won Ryu Hyoung Chan Kim Dr. Sung Won Yoon Byoung Jin Suh Prof. Chang Seop Hong Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(15):3661-3665
Two‐step magnetic transitions : An azide‐bridged 1D MnIII coordination polymer with a unique single end‐on mode was prepared; it displayed atypical antiferromagnetic couplings and field‐induced two‐step magnetic transitions (see figure). The spin‐canted phenomenon in the antiferromagnetic chain complex plays a pivotal role in establishing the slow magnetic relaxation.
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Andreas Sonnauer Frank Hoffmann Dr. Michael Fröba Prof. Dr. Lorenz Kienle Prof. Dr. Viola Duppel Matthias Thommes Dr. Christian Serre Gérard Férey Prof. Dr. Norbert Stock Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(21):3714-3714
Highly porous and stable metal–organic frameworks, isoreticular to MIL‐101 and with cage diameters of 39 and 46 Å, are obtained by replacement of the 1,4‐benzenedicarboxylate ligands in that framework with 2,6‐naphthalenedicarboxylate. In their Communication on page 3791 ff. , N. Stock and co‐workers report high‐throughput methods used to optimize reaction conditions and characterization of this MTN zeolite analogue by a combination of structure simulation, electron microscopy, and sorption measurements.
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Raffael Koller Kyrill Stanek Daniel Stolz Dr. Raphael Aardoom Katrin Niedermann Antonio Togni Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(24):4332-4336
A (fluor)ry of activity : The transfer of an intact trifluoromethyl group from a hypervalent iodine reagent to an aliphatic alcohol occurs smoothly upon activation by zinc bis(triflimide). This constitutes a straightforward method for the preparation of trifluoromethoxy alkyl derivatives, compounds otherwise difficult to access.
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Stephen A. Morin Young‐Hye La Dr. Chi‐Chun Liu Jeremy A. Streifer Dr. Robert J. Hamers Prof. Paul F. Nealey Prof. Song Jin Prof. 《Angewandte Chemie (International ed. in English)》2009,48(12):2135-2139
Growing in line: The surface chemistry of self‐assembled nanostructured block copolymers is used to control the sites at which semiconducting metal sulfide nanocrystals nucleate and grow on a surface directly from aqueous solutions. This process is a new and general strategy for the bottom‐up assembly of functional nanocrystalline materials for a variety of applications.
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Anusree Mukherjee Marlène Martinho Dr. Emile L. Bominaar Dr. Eckard Münck Prof. Dr. Lawrence Que Jr. Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(10):1780-1783
Picky ferryl : The complex [Fe(Tp)(BF)] (Tp=hydrotris(3,5‐diphenylpyrazolyl)borate; BF=benzoylformate) reacts with O2 to generate an oxidant (see picture; O red, pink; Fe yellow; N blue; C gray; H white) that oxidizes added hydrocarbons shape‐selectively. Discrimination derives from a cleft formed by two phenyl groups of the Tp ligand, favoring oblate spheroidal substrates.