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Graphical Abstract Angew. Chem. Int. Ed. 332005

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Contents
The following Communications have been judged by at least two referees to be “very
important papers” and will be published online at www.angewandte.org soon:
K. Haraguchi,* H.-J. Li
Control of the Coil-to-Globule Transition of
Poly(N-isopropylacrylamide) and Ultrahigh Mechanical
Properties in Nanocomposite Hydrogels
T. Buskas, S. Ingale, G.-J. Boons*
Towards a Fully Synthetic Carbohydrate-Based Anticancer
Vaccine: Synthesis and Immunological Evaluation of a Lipidated
Glycopeptide Containing the Tumor-Associated Tn Antigen
A. C. Filippou,* G. Schnakenburg, A. I. Philippopoulos,
N. Weidemann
Bonding Analysis of the MGeGeM Chain in the Germylidyne
Complexes trans,trans-[Cl(depe)2MGeGeM(depe)2Cl]
M. Veith*
Cubane-Type Li4H4 and Li3H3Li(OH): Stabilized in Molecular
Adducts with Alane
S. Protti, M. Fagnoni,* A. Albini*
Photochemical Cross-Coupling Reactions of Electron-Rich Aryl
Chlorides and Aryl Esters with Alkynes: A Metal-Free Alkynylation
V. Lavallo, Y. Canac, C. Pr-sang, B. Donnadieu, G. Bertrand*
Stable Cyclic (Alkyl)(amino)carbenes as Rigid or Flexible, Bulky,
Electron-Rich Ligands for Transition-Metal Catalysts
Meeting Review
Kaleidoscope of Catalysis: Heidelberg Forum of Molecular Catalysis 2005
M. Oestreich
5166
Books
The Life and Work of Friedrich W#hler
(1800–1882)
Johannes B+ttner
reviewed by H. Hopf
5168
Our Lives
Istv.n Hargittai
reviewed by W. Schroth
5169
At the interface: The supramolecular
organization of nanometer-scale objects
is of great interest in the field of applied
nanotechnology. Liquid–liquid interfaces
can provide an alternative to current
methods for the formation of highly
ordered structures through the selfassembly of nanoparticles, nanocrystals,
and even viruses (see picture). The concept is generally applicable and can be
transferred to other interfaces, such as
those of polymers.
Highlights
Self-Assembly
W. H. Binder*
5172 – 5175
Supramolecular Assembly of
Nanoparticles at Liquid–Liquid Interfaces
5154
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Angew. Chem. Int. Ed. 2005, 44, 5154 – 5163
Angewandte
Chemie
Minireviews
Electrophilic Reagents
M. Sugiura, S. Kobayashi*
5176 – 5186
N-Acylhydrazones as Versatile
Electrophiles for the Synthesis of
Nitrogen-Containing Compounds
Stable imine surrogates: N-Acylhydrazones are readily prepared from aldehydes
and ketones with N-acylhydrazines. As
imine equivalents in the presence of metal
catalysts, they effectively promote reactions with a variety of nucleophiles (see
scheme). Substrate N-acyl groups chelate
the metal catalyst, which increases substrate electrophilicity and stereochemical
control. The hydrazide products of Nacylhydrazones are useful chiral building
blocks for various nitrogen-containing
compounds.
Reviews
Azides
Tricky reagents: Besides their special
thermal properties, organic azides also
have unique reactivities (see scheme).
This Review covers the use of organic
azides in fundamental reactions as well as
more recent developments in the Staudinger ligation, in copper-catalyzed dipolar cycloadditions, and in heterocyclic
synthesis.
S. Br:se,* C. Gil, K. Knepper,
V. Zimmermann
5188 – 5240
Organic Azides: An Exploding Diversity of
a Unique Class of Compounds
Communications
For the USA and Canada:
ANGEWANDTE CHEMIE International
Edition (ISSN 1433-7851) is published weekly
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Meacham Ave., Elmont, NY 11003. Periodicals
Angew. Chem. Int. Ed. 2005, 44, 5154 – 5163
On cores: Silver carboxylates react with a
mixture of S(tBu)SiMe3 and S(SiMe3)2 (in
the presence of a bidentate phosphine
ligand) to yield [Ag123S35(StBu)50] (1) or
[Ag344S124(StBu)96] (2, see picture:
blue Ag+, red S atoms of the StBu groups,
yellow S2, gray C) with maximum diameters of 2.5 (1) or 3.7 nm (2). These
clusters can be described as core–shell
particles with the {(Ag2S)35Ag3} (1) and
the {(Ag2S)124} (2) cores surrounded by
shells of AgStBu units.
Cluster Compounds
postage paid at Jamaica NY 11431. US POSTMASTER: send address changes to Angewandte
Chemie, Wiley-VCH, 111 River Street, Hoboken,
NJ 07030. Annual subscription price for institutions: US$ 4948.00/4498.00 (valid for print
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individuals who are personal members of a
national chemical society, or whose institution
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Wiley-VCH prices are exclusive VAT.
D. Fenske,* C. E. Anson, A. Eichh#fer,
O. Fuhr, A. Ingendoh, C. Persau,
C. Richert
5242 – 5246
Syntheses and Crystal Structures of
[Ag123S35(StBu)50] and [Ag344S124(StBu)96]
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
5155
Angewandte
Chemie
Protein Structures
Mutations in the transcription factor p53
enhance one’s predisposition to cancer.
Mutational studies show that double salt
bridges are key elements for the dimerization of p53, its cooperative binding to
DNA, and thus its proper function as a
tumor suppressor (see picture). This
might explain certain germ-line mutations
found in patients with Li–Fraumeni syndrome.
A. Dehner, C. Klein, S. Hansen, L. M+ller,
J. Buchner, M. Schwaiger,
H. Kessler*
5247 – 5251
Cooperative Binding of p53 to DNA:
Regulation by Protein–Protein
Interactions through a Double Salt Bridge
Drug Delivery
S. Keller,* I. Sauer, H. Strauss, K. Gast,
M. Dathe, M. Bienert
5252 – 5255
Detergent activity is conferred upon a cellpenetrating peptide by dipalmitoylation,
and the peptide can incorporate large
amounts of phospholipid into supramolecular particles with unique physicochemical properties. These nanocarriers
combine the advantages of both lipo-
somes and micelles as they offer a
membrane-like environment in spite of
their small size, thus preserving the
biofunctionality of the vector peptide and
affording efficient internalization into live
cells.
Membrane-Mimetic Nanocarriers Formed
by a Dipalmitoylated Cell-Penetrating
Peptide
Zwitterionic structures with very low lying
triplet states are the dominant characteristics of the first hexaazaacridine, 3,5,7,9tetraphenylhexaazaacridine (TPH-acridine, see picture), and the analogous
TPH-anthracene. The structure and spectroscopic properties were studied experimentally and by DFT calculations and
analysis of nucleus-independent chemical
shifts.
Antiaromatic Species
Bridging the gap: Encapsulation by “soft”
organic ligands is the key to the isolation
of complexes containing “hard” MoVI-OBiV and MoVI-O-BiIII units (see example),
which might be regarded as molecular
models for pivotal species on the surfaces
of heterogeneous catalysts.
Coordination Chemistry
Angew. Chem. Int. Ed. 2005, 44, 5154 – 5163
P. Langer,* A. Bodtke, N. N. R. Saleh,
H. G#rls, P. R. Schreiner*
5255 – 5259
3,5,7,9-Tetraphenylhexaazaacridine:
A Highly Stable, Weakly Antiaromatic
Species with 16 p Electrons
S. Roggan, C. Limberg,*
B. Ziemer
5259 – 5262
Molecular Compounds with Mo-O-Bi
Moieties
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
5157
Contents
Multicomponent Micelles
Like a doughnut with a raspberry filling:
ABC triblock copolymers, composed of a
hydrophilic block with morpholinium
units (blue in the picture), a hydrophobic
hydrocarbon block (red), and a hydrophobic fluorocarbon-rich block (black),
self-assemble in water to form multicompartment micelles with a hydrophilic
corona and a hydrophobic core with
nanometer-scale subdomains.
S. Kubowicz, J.-F. Baussard, J.-F. Lutz,
A. F. Th+nemann, H. von Berlepsch,
A. Laschewsky*
5262 – 5265
Multicompartment Micelles Formed by
Self-Assembly of Linear ABC Triblock
Copolymers in Aqueous Medium
Asymmetric Synthesis
C. Herber, B. Breit*
5267 – 5269
Enantioselective Total Synthesis and
Determination of the Absolute
Configuration of the 4,6,8,10,16,18Hexamethyldocosane from Antitrogus
parvulus
A copper-catalyzed sp3–sp3 cross-coupling
for fragment coupling in a total synthesis
is demonstrated. The diastereo- and
enantioselective total synthesis of the
4,6,8,10,16,18-hexamethyldocosanes
highlights the synthetic power of deoxy-
propionate construction based on an
ortho-diphenylphosphanylbenzoyl (oDPPB)-directed and copper-mediated
allylic substitution with Grignard reagents
(see scheme).
Carbenes with a twist: A seven-membered
N-heterocyclic carbene (NHC) ligand is
prepared from an amidinium precursor,
derived from 2,2’-dinitrobiphenyl, and
yields the NHC–PdII complex [PdCl(allyl)(NHC)] (see scheme). This carbene fra-
mework exhibits a tortional twist that
results in axial symmetry. This ligand class
can be readily modified and is attractive
for future application in asymmetric catalysis.
A radical transformation! An efficient
radical cascade reaction leads to functionalized five-membered rings. Alkenyl
radicals are generated from readily available terminal alkynes and a dialkyl phos-
phite. This tin-free procedure can be run
under one-pot conditions (no slow addition), is high yielding, and can be applied
to the assembly of fused bicyclic compounds (see scheme).
Organometallic Chemistry
C. C. Scarborough, M. J. W. Grady,
I. A. Guzei, B. A. Gandhi, E. E. Bunel,
S. S. Stahl*
5269 – 5272
PdII Complexes Possessing a SevenMembered N-Heterocyclic Carbene
Ligand
Radical Reactions
F. Beaufils, F. DSnTs,
P. Renaud*
5273 – 5275
Dimethyl Phosphite Mediated Hydrogen
Atom Abstraction: A Tin-Free Procedure
for the Preparation of Cyclopentane
Derivatives
5158
www.angewandte.org
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Angew. Chem. Int. Ed. 2005, 44, 5154 – 5163
Angewandte
Chemie
Homogeneous Catalysis
S. Ma,* P. Lu, L. Lu, H. Hou, J. Wei, Q. He,
Z. Gu, X. Jiang, X. Jin
5275 – 5278
The beauty and power of transition-metalcatalyzed reactions has been demonstrated by the one-step synthesis of steroid
scaffolds from readily available allenes.
The best results (57–73 % yield) were
obtained using trans-[RhCl(CO)(PPh3)2] as
the catalyst in toluene (see scheme;
E = CN, CO2Me, SO2Ph, Ts = toluene-4sulfonyl).
What Can a Metal Catalyst Do with
Allenes? One-Step Formation of Steroid
Scaffolds from Readily Available Starting
Materials
Heterogeneous Catalysis
Coordinating the attack: A theoretical
approach based on first-principles calculations and a kinetic model has shown
that the partial hydrogenation of the C=O
or C=C bonds in acrolein on a Pt(111)
catalyst is controlled by the balance
between the hydrogenation steps on the
surface and the desorption of the partially
hydrogenated products. The scheme
shows the four possible surface intermediates and the two products.
D. Loffreda,* F. Delbecq, F. VignS,
P. Sautet
5279 – 5282
Catalytic Hydrogenation of Unsaturated
Aldehydes on Pt(111): Understanding the
Selectivity from First-Principles
Calculations
Carbene Ligands
D. Bacciu, K. J. Cavell,* I. A. Fallis,
L.-l. Ooi
5282 – 5284
Wrong way round: Imidazolium salts
blocked at C2 undergo oxidative addition
to a Pt0 center at C4/C5 (see scheme;
nbe = norbornene, IMes = 1,3-bis(2,4,6trimethylphenyl)imidazolin-2-ylidene).
The resulting carbene ligands, which are
bound the “wrong way” are susceptible, in
common with their “normal” counterparts, to reductive elimination reactions
to regenerate Pt0 complexes and imidazolium salts.
Approaching El Dorado: A gold catalyst
has been discovered that transfers a
carbene unit from ethyl diazoacetate to
aromatic substrates (see scheme) as well
as olefins, amines, and alcohols. The
insertion of carbene units into the CH
bonds of the aromatic ring of benzene,
toluene, and styrene is a novel reaction.
R = H, CH3, CH=CH2 ; IPr = 1,3-bis(diisopropylphenyl)imidazol-2-ylidene.
Angew. Chem. Int. Ed. 2005, 44, 5154 – 5163
Platinum-Mediated Oxidative Addition
and Reductive Elimination of Imidazolium
Salts at C4 and C5
Carbene Chemistry
M. R. Fructos, T. R. Belderrain,
P. de FrSmont, N. M. Scott, S. P. Nolan,*
M. M. DXaz-Requejo,*
P. J. PSrez*
5284 – 5288
A Gold Catalyst for Carbene-Transfer
Reactions from Ethyl Diazoacetate
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
5159
Contents
Porphyrinoids
A. Berlicka, L. Latos-Grażyński,*
T. Lis
5288 – 5291
Dithiaethyneporphyrin: An Atypical
[18]Triphyrin(4.1.1) Frame for Contracted
Porphyrins
Fusion of the structural motifs 21,23dithiaporphyrin and acetylene yields the
18-p-aromatic [18]triphyrin(4.1.1) framework (see structure; C gray, N blue, S yellow). The butyne moiety that joins the two
thiophene rings reveals a slight distortion
from linearity, showing a bowlike deformation directed out of the macrocycle.
Higher-Coordinate Si Compounds
R. Tacke,* R. Bertermann, C. Burschka,
S. Dragota
5292 – 5295
A Zwitterionic Spirocyclic Pentacoordinate
Silicon Compound Synthesized in Water
by SiO and SiC Bond Cleavage
Remarkable hydrolytic stability in the
range pH 7.0–8.0 is exhibited by the
zwitterionic l5Si-silicate 1, which can even
be prepared in water and forms a stable
Molecular Devices
D.-H. Qu, Q.-C. Wang,
H. Tian*
5296 – 5299
A Half Adder Based on a Photochemically
Driven [2]Rotaxane
A molecular abacus: In a [2]rotaxane that
mimicks a half adder with distinct AND
and XOR logic gates, all the inputs (I) and
outputs (O) are photochemical (see
scheme; F = fluorescence, A = absorbance). Reversible E!Z photoisomerization about two double bonds (shown in
red and dark blue) in the thread molecule
leads to four conformers that have different spectral properties.
Green Chemisty
N. Zheng, X. Bu, H. Vu,
P. Feng*
5299 – 5303
Open-Framework Chalcogenides as
Visible-Light Photocatalysts for Hydrogen
Generation from Water
5160
www.angewandte.org
hydrate 1·H2O. The synthetic route to 1
and the structure of the zwitterion in the
crystal (O red; N blue; Si green; C gray)
are shown in the picture.
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Light work: Open-framework chalcogenides are efficient visible-light photocatalysts for the reduction of water to hydrogen. These materials contain 3D covalent
superlattices built from nanosized supertetrahedral clusters (see picture). Unlike
dense semiconductors, they allow the
easy incorporation of dye sensitizers
within their channels, which can further
enhance their photocatalytic response in
the visible-light region.
Angew. Chem. Int. Ed. 2005, 44, 5154 – 5163
Angewandte
Chemie
Organolanthanides
H. M. Dietrich, G. Raudaschl-Sieber,
R. Anwander*
5303 – 5306
Trimethylyttrium and Trimethyllutetium
Complexes in disguise: Homoleptic
[Ln(AlMe4)3] (Ln = Y, Lu) complexes are
effectively masked [LnMe3]n species,
which are produced reversibly upon equimolar addition of a Lewis base to the
former. Compounds [LnMe3]n are thermally stable and readily form peralkylated
heterobimetallic complexes with alkylaluminum, -gallium, and -magnesium
reagents (see scheme).
Asymmetric Catalysis
M. K. Brown, S. J. Degrado,
A. H. Hoveyda*
The first generally effective method for
catalytic asymmetric conjugate addition
(ACA) of dialkylzinc reagents to unsaturated furanones and pyranones (see
scheme) with different steric and electro-
nic properties is reported. Synthesis, isolation, and characterization of catalytically
active and air-stable chiral Cu–peptide
complexes are also described.
Simple but effective: The intrusion/extrusion cycle of a nonwetting fluid in a
hydrophobic solid can be described by
simple models and simulation methods
found useful for studying gas adsorption
in nanoporous materials. The water confined to hydrophobic spaces of nanoscopic dimensions in the zeolite silicalite-1
is shown to be a strongly depleted and
highly inhomogeneous fluid (see picture).
The one-electron oxidation of compounds
1H–3H occurs by a proton-coupled electron-transfer mechanism to produce a
phenoxyl radical hydrogen-bonded to an
imidazolium carbon atom. Thus, these
compounds serve as analogues for tyrosyl DC in photosystem II. This insight was
obtained from a combination of W-band
EPR spectroscopy and DFT calculations.
Angew. Chem. Int. Ed. 2005, 44, 5154 – 5163
5306 – 5310
Highly Enantioselective Cu-Catalyzed
Conjugate Additions of Dialkylzinc
Reagents to Unsaturated Furanones and
Pyranones: Preparation of Air-Stable and
Catalytically Active Cu–Peptide Complexes
Zeolites
N. Desbiens, I. Demachy, A. H. Fuchs,*
H. Kirsch-Rodeschini, M. Soulard,
J. Patarin
5310 – 5313
Water Condensation in Hydrophobic
Nanopores
Radical Cations
L. Benisvy,* R. Bittl, E. Bothe, C. D. Garner,
J. McMaster, S. Ross, C. Teutloff,
F. Neese*
5314 – 5317
Phenoxyl Radicals Hydrogen-Bonded to
Imidazolium: Analogues of Tyrosyl DC of
Photosystem II: High-Field EPR and DFT
Studies
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
5161
Contents
Mesoporous Silicates
A. E. Garcia-Bennett,* N. Kupferschmidt,
Y. Sakamoto, S. Che,
O. Terasaki
5317 – 5322
Synthesis of Mesocage Structures by
Kinetic Control of Self-Assembly in
Anionic Surfactants
Varying the time between adding a costructure-directing agent and a silica
source to an anionic surfactant template
results in either well-ordered cubic or a
novel tetragonal (P42/mnm) mesocage
material by arrangement of micellar
spheres of various sizes. The image shows
the high-resolution transmission electron
micrograph of the tetragonal structure
and the corresponding electron diffraction
pattern (inset).
Host–Guest Systems
K. Nakabayashi, M. Kawano,*
M. Fujita*
5322 – 5325
pH-Switchable Through-Space Interaction
of Organic Radicals within a SelfAssembled Coordination Cage
Zeolites
C. Minkowski,
G. Calzaferri*
5325 – 5329
F#rster-Type Energy Transfer along a
Specified Axis
Structural Biochemistry
F. Zhao, Q. Zhao, K. F. Blount, Q. Han,
5329 – 5334
Y. Tor, T. Hermann*
Molecular Recognition of RNA by
Neomycin and a Restricted Neomycin
Derivative
5162
www.angewandte.org
Twinned spins yield triplets: The throughspace interaction of non-associative
stable organic radicals within a selfassembled coordination cage (see
scheme) is controlled by pH. The amino
group of the radical can be protonated,
and the affinity of the radicals for the host
consequently decreases at low pH owing
to coulombic repulsion. This leads to their
release, as observed by ESR spectroscopy.
Quasi-1D transport of electronic excitation energy in dye-loaded zeolite L was
observed when a spacer molecule was
introduced between the donor and the
acceptor dyes to separate them locally
(see picture). In the system shown, the
donor–spacer and spacer–acceptor phase
boundaries are both diffuse. Alternatively,
all the donors can be fixed at the same
position and only the spacer–acceptor
phase boundary is diffuse.
The preorganized presentation of functional groups in the antibiotic neomycin
(green) is exploited to obtain a conformationally restricted aminoglycoside
(yellow) by regioselective intramolecular
cyclization. X-ray crystallography data
show how the natural product and the
derivative recognize the RNA target motif
that is the binding site of aminoglycoside
antibiotics.
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Angew. Chem. Int. Ed. 2005, 44, 5154 – 5163
Angewandte
Chemie
Supramolecular Chemistry
M.-C. Bl+m,* E. Ćavar, M. Pivetta,
F. Patthey, W.-D. Schneider 5334 – 5337
Nested assembly: Chiral molecules of
5,6,11,12-tetraphenylnaphthacene
(rubrene) organize spontaneously into
homochiral supramolecular architectures
of increasing complexity. Adsorbed indi-
vidual molecules self-assemble enantioselectively into chiral pentagonal supermolecules, which act as building blocks
for the formation of chiral supramolecular
decagons (see STM images).
Conservation of Chirality in a Hierarchical
Supramolecular Self-Assembled Structure
with Pentagonal Symmetry
Host–Guest Chemistry
All clicking into place: Self-complementarity between a bis(crown ether) derivative and a bisammonium fullerene leads
to the formation of a stable noncovalent
macrocyclic 1:1 complex (see schematic
representation). The binding constant for
this complex is three orders of magnitude
larger than that for other closely related
systems as a result of the two-center host–
guest topography.
U. Hahn, M. Elhabiri, A. Trabolsi,
H. Herschbach, E. Leize,
A. Van Dorsselaer,* A.-M. Albrecht-Gary,*
J.-F. Nierengarten*
5338 – 5341
Supramolecular Click Chemistry with a
Bisammonium-C60 Substrate and a
Ditopic Crown Ether Host
The issues for August 2005 appeared online on the following dates
Issue 29: July 8 · Issue 30: July 18 · Issue 31: July 29 · Issue 32: August 8.
Service
Keywords
5342
Authors
5343
Angewandte’s
Sister Journals
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Angew. Chem. Int. Ed. 2005, 44, 5154 – 5163
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
5344 – 5345
5347
www.angewandte.org
5163
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