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Graphical Abstract Angew. Chem. Int. Ed. 222004

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Contents
The following Communications are available online (in Wiley InterScience). You can find them, as
well as forthcoming Reviews, Highlights, and Essays, at www.angewandte.org, under Early View.
M. K)hn, R. Breinbauer*:
The Staudinger Ligation—A Gift to Chemical Biology
DOI: 10.1002/anie.200401744
Published online: May 12, 2004
P. A. Wender,* N. M. Deschamps, T. J. Williams:
Intermolecular Dienyl Pauson–Khand Reaction
DOI: 10.1002/anie.200454117
Published online: May 13, 2004
T. K. Maji, K. Uemura, H.-C. Chang, R. Matsuda, S. Kitagawa*:
Expanding and Shrinking Porous Modulation Based on PillaredLayer Coordination Polymers Showing Selective Guest Adsorption
DOI: 10.1002/anie.200453923
Published online: May 12, 2004
Articles judged by the referees or the editor as being either very important or very urgent are immediately edited, proof-read, and electronically
published once the manuscript has arrived in the editorial office in its final form. As long as there is no page number available these articles should
be cited in the following manner:
Author(s), Angew. Chem. Int. Ed., online publication date, DOI.
Web Sites
http://www.colby.edu/chemistry/
NMR/NMR.html
Internet-Based Spectroscopy Tools:
Instructive Aids for Molecular-Structure
Analysis?
M. Schfer and N. Schlrer
2878
2879
Christopher Walsh
reviewed by H. Brtz-Oesterhelt
Ayusman Sen
reviewed by A. Bastero
Books
Antibiotics
Catalytic Synthesis of Alkene–Carbon
Monoxide Copolymers and
Cooligomers
2880
Highlights
Molecular Electronics
M. Mayor,* H. B. Weber*
2882 – 2884
Statistical Analysis of Single-Molecule
Junctions
2868
Establishing contact: Recent progress in
the investigation of single-molecule contacts established in an electrochemical
scanning tunneling experiment are
described (see picture). The setup allows
for the successive formation of many
hundreds of junctions and a statistical
analysis of the voltage dependence of the
electrical current. This method is a new
reliable tool to characterize molecular
junctions and contributes to elucidating
the potential of molecular electronics.
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
Angew. Chem. Int. Ed. 2004, 43, 2868 – 2874
Angewandte
Chemie
Reviews
Snapshots of excited-state molecular
structures in solution during chemical
reactions serve as the basis for understanding reaction intermediates. The
method of choice for obtaining such
structures is photo-chemical excitation by
a laser pulse and subsequent analysis by
time-resolved X-ray absorption spectroscopy. (X-rays generated by third-generation synchrotron sources; see picture of
the Advanced Photon Source of the
Argonne National Laboratory, Illinois).
Pump–Probe Techniques
L. X. Chen*
2886 – 2905
Taking Snapshots of Photoexcited
Molecules in Disordered Media by Using
Pulsed Synchrotron X-rays
Communications
Usually viewed as intermediates that
become long-lived at low temperatures in
superacidic media, simple alkyl carbocations such as the tert-butyl cation can be
isolated as stable salts at room temperature when partnered with inert carborane
anions. The X-ray crystal structures of tertbutyl (depicted), tert-pentyl, and methylcyclopentyl cations have been determined
with CHB11Me5X6 counterions (X = Br or
Cl). C blue; H white; B yellow; X green.
Carbocations
T. Kato, C. A. Reed*
2908 – 2911
Putting tert-Butyl Cation in a Bottle
Synthetic Methods
Z. Tan, E.-i. Negishi*
A decrease in the number of linear
synthetic steps and an increase in efficiency have been realized in the synthesis
of the side chain of scyphostatin. An
efficient and selective synthesis of a,wdifunctional reduced polypropionates
from methyl 3-hydroxy-2-methylpropionate through the use of a Zr-catalyzed
asymmetric carboalumination has been
developed (see scheme, TBS = tert-butyldimethylsilyl).
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Angew. Chem. Int. Ed. 2004, 43, 2868 – 2874
www.angewandte.org
2911 – 2914
An Efficient and General Method for the
Synthesis of a,w-Difunctional Reduced
Polypropionates by Zr-Catalyzed
Asymmetric Carboalumination: Synthesis
of the Scyphostatin Side Chain
individuals who are personal members of a
national chemical society, or whose institution
already subscribes, or who are retired or selfemployed consultants, print only: Europe
E 248.00/outside Europe US$ 378.00. Postage
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prices are exclusive VAT.
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2869
Contents
Carbohydrate Synthesis
M. H. D. Postema,* J. L. Piper,
V. Komanduri, L. Liu
2915 – 2918
A Double Ring-Closing Metathesis
Approach for the Synthesis of
b-C-Trisaccharides
Good things come in threes: A variety of
b-C-trisaccharides have been successfully
synthesized by double ring-closing metathesis, which provides the products in
excellent overall yield after functionaliza-
Surface Chemistry
S. Linic, H. Piao, K. Adib,
M. A. Barteau*
2918 – 2921
Ethylene Epoxidation on Ag: Identification
of the Crucial Surface Intermediate by
Experimental and Theoretical Investigation of its Electronic Structure
Intermediate success: A combination of
high-resolution X-ray photoelectron
spectroscopy and density functional
Host–Guest Chemistry
New Clathrate Hydrate Structure: HighPressure Tetrahydrofuran Hydrate with
One Type of Cavity
Dendrimers
Regenerable and reusable dendritic
catalysts have been synthesized by the
ionic assembly of polyammonium dendrimers and polyoxometalate (POM) trianionic units. These dendrimers (see
example depicted, in which the POM is
[PO4{WO(O2)2}4]3) are found to catalyze,
at ambient temperature, the quantitative
epoxidation of olefins by H2O2 in water/
CDCl3 and the selective and quantitative
oxidation of thioanisole to its sulfone.
L. Plault, A. Hauseler, S. Nlate, D. Astruc,*
J. Ruiz, S. Gatard,
R. Neumann
2924 – 2928
Synthesis of Dendritic Polyoxometalate
Complexes Assembled by Ionic Bonding
and Their Function as Recoverable and
Reusable Oxidation Catalysts
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
theory allows the electronic structures of
adsorbates to be probed to an unprecedented level of detail. By using these
techniques, the adsorption of ethylene
oxide onto an Ag(111) surface has been
shown to result in the formation of an
unsymmetrical surface oxametallacycle
structure (see picture).
Water cages: A water framework consisting of uniform space-filling polyhedral
cages containing tetrahydrofuran molecules has been detected in a new clathrate
hydrate formed under a pressure of
0.8 GPa. Topologically the cage represents
a space-filling tetradecahedron with four
tetra-, four penta-, and six hexagonal faces
(see picture).
A. V. Kurnosov,* V. Yu. Komarov,
V. I. Voronin, A. E. Teplykh,
A. Yu. Manakov
2922 – 2924
2870
tion of the newly formed double bonds
(see scheme). The precursor olefin–enol
ethers were prepared by Takai methylenation of the appropriate diesters.
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Angew. Chem. Int. Ed. 2004, 43, 2868 – 2874
Angewandte
Chemie
Alkene Isomerization
A radical intermediate is generated when
methylidenecyclopentane (1) is isomerized by SO2 into 1-methylcyclopentene (3)
through the formation of a polysulfone
polymer (PS), which first abstracts a
hydrogen atom from the alkene. The allyl
radical intermediate 2 abstracts a hydrogen atom from another alkene molecule 1,
to yield the isomerized alkene and regenerating the allyl radical. Polysulfones are
organic catalysts.
D. Marković, P. Vogel*
Polysulfones: Catalysts for Alkene
Isomerization
Born from a simple amino acid … the
potent hepatotoxic cyanobacterial alkaloid
7-epicylindrospermopsin (see picture)
has been synthesized through a concise
asymmetric eighteen-step route. An
intramolecular 1,3-dipolar cycloaddition
and a nitroaldol reaction are key steps in
the construction of the natural product
from a precursor with a single stereogenic
center.
The impact of the anion on the assembly
of extended 2D structures has been
demonstrated by two distinct luminescent
2D lattices. Shown here is the macrocyclic
cloverleaf-shaped cavity obtained from the
reaction of a starburst ligand with
Ag(NO3). Use of the triflate salt instead
results in a honeycomb-shaped cavity.
Natural Product Synthesis
R. E. Looper,
R. M. Williams*
2930 – 2933
A Concise Asymmetric Synthesis
of the Marine Hepatotoxin
7-Epicylindrospermopsin
Coordination Networks
C. Seward, W.-L. Jia, R.-Y. Wang,
G. D. Enright, S. Wang*
2933 – 2936
Luminescent 2D Macrocyclic Networks
Based on Starburst Molecules:
[{Ag(CF3SO3)}1.5(tdapb)] and
[{Ag(NO3)}3(tdapb)]
HIV Inhibition
Barring infection: A new CD4-binding
peptidomimetic (see ball-and-stick structure; CD4 is shown in green) has been
designed and synthesized as an entry
inhibitor of the HIV virus. The binding
affinity of the peptidomimetic for CD4 is
40 mm, which is 150-fold better than that
of the lead peptide NMWQKVGTPL. The
mimetic also has a lower molecular
weight and a higher proteolytic stability
than the lead peptide.
Angew. Chem. Int. Ed. 2004, 43, 2868 – 2874
2928 – 2930
A. T. Neffe, B. Meyer*
2937 – 2940
A Peptidomimetic HIV-Entry Inhibitor
Directed against the CD4 Binding Site of
the Viral Glycoprotein gp120
www.angewandte.org
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2871
Contents
Phosphorylation Reporters
C.-W. Lin, A. Y. Ting*
2940 – 2943
A Genetically Encoded Fluorescent
Reporter of Histone Phosphorylation in
Living Cells
Dendrimeric Structures
W.-S. Li, D.-L. Jiang,*
T. Aida*
2943 – 2947
Photoluminescence Properties of Discrete
Conjugated Wires Wrapped within
Dendrimeric Envelopes: “Dendrimer
Effects” on p-Electronic Conjugation
Host–Guest Systems
J. L. Atwood,* L. J. Barbour,*
A. Jerga
2948 – 2950
A New Type of Material for the Recovery of
Hydrogen from Gas Mixtures
An increase in FRET indicates phosphorylation of histone H3 at serine 28. The
protein-based reporter (see picture)
responds to phosphorylation through
intramolecular complexation between a
substrate domain derived from histone
H3 and a linked phosphoserine-recognition domain. The reporter is also effective
inside living mammalian cells. FRET =
fluorescence resonance energy transfer.
Third-generation dendrimers have been
used to enable the synthesis and isolation
of a series of spatially isolated, discrete
conjugated wires G3-n (where n is the
number of repeating monomer units, see
schematic representation), including 147nm long G3-64, which contains 192 aromatic rings and 256 triple bonds in the
backbone. Photochemical studies show
there is enhanced p-electronic conjugation in these systems.
Molecular gas works: p-tert-Butylcalix[4]arene crystals possess large interstitial
cavities when grown by sublimation and,
although nonporous, are able to absorb
and retain gases such as O2, N2, and CO2
under near-ambient conditions. H2 is not
retained and thus the material can be
used to effect the separation of H2 from
gas mixtures. The gas can be removed by
evacuation or immersion of the crystals in
nitrobenzene (see picture).
Porphyrin Derivatives
Adding to the confusion: [3þ2] coupling
of confused tripyrrane and confused
dipyrromethane dicarbinol, followed by
oxidation, results in the synthesis of mesopentafluorophenyl-substituted, doubly
N-confused, oxo-substituted pentaphyrins
(see X-ray crystal structure; green: F, blue:
N, red: O). The oxopyrrole moieties have
been shown to readily form intra- and
intermolecular hydrogen bonds.
A. Srinivasan, T. Ishizuka, H. Maeda,
H. Furuta*
2951 – 2955
Doubly N-Confused Pentaphyrins
2872
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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Angew. Chem. Int. Ed. 2004, 43, 2868 – 2874
Angewandte
Chemie
Heterogeneous Catalysis
Incomplete carbonization of sulfoaromatic hydrocarbons results in a carbon
material that consists of small polycyclic
aromatic carbon sheets with attached
SO3H groups (see picture). This insoluble
solid acid exhibits remarkably high activity
in the formation of ethyl acetate, the
hydrolysis of cyclohexyl acetate, and the
hydration of 2,3-dimethyl-2-butene.
M. Hara,* T. Yoshida, A. Takagaki,
T. Takata, J. N. Kondo, S. Hayashi,
K. Domen
2955 – 2958
A Carbon Material as a Strong Protonic
Acid
Defined micelles: A completely uniform
and structurally precise micelle spontaneously formed by exactly seven amphiphilic dendro-calixarene molecules in
aqueous solution has been determined by
cryo-TEM and 3D reconstruction techniques. The picture shows seven calixarene head groups, which have been fit
visually into the reconstructed density
map of the micelle.
Micelles
M. Kellermann, W. Bauer, A. Hirsch,*
B. Schade, K. Ludwig,
C. BRttcher*
2959 – 2962
The First Account of a Structurally
Persistent Micelle
Bioorganic Chemistry
C. DSrr, D. Hoffmeister, S.-V. Wohlert,
K. Ichinose, M. Weber, U. von Mulert,
J. S. Thorson, A. Bechthold* 2962 – 2965
Sweet success: A natural product glycosyltransferase, UrdGT2 from Streptomyces
fradiae TS2717, is the first glycosyltransferase able to catalyze both C-glycosidic
and O-glycosidic sugar transfers. These
results shed new light on the mechanisms
of C-glycosylation of aromatic compounds, which is significant for chemoenzymatic drug lead derivatization as well
as for enzymology.
Organosilicon Chemistry
The reduction of Tip2SiCl2 by finely dispersed lithium powder directly affords the
disilenide 1 (see picture), the structure of
which could be characterized by X-ray
crystallography. The reaction of 1 with
Me3SiCl leads to the corresponding
asymmetrical disilene. The ready availability of 1 is expected to open new
possibilities for the synthesis of disilenes
in general. Tip = 2,4,6-iPr3C6H2
Angew. Chem. Int. Ed. 2004, 43, 2868 – 2874
The Glycosyltransferase UrdGT2 Catalyzes
Both C- and O-Glycosidic Sugar Transfers
D. Scheschkewitz*
2965 – 2967
A Silicon Analogue of Vinyllithium:
Structural Characterization of a Disilenide
www.angewandte.org
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2873
Contents
Organomagnesium Reagents
C. Duplais, F. Bures, I. Sapountzis,
T. J. Korn, G. Cahiez,
P. Knochel*
2968 – 2970
An Efficient Synthesis of Diaryl Ketones by
Iron-Catalyzed Arylation of Aroyl Cyanides
An alternative to acyl chlorides: Iron(iii)catalyzed arylation of aroyl and heteroaroyl cyanides with aryl magnesium
reagents (see example in scheme)
provides an easy and mild approach to
polyfunctionalized diaryl ketones in yields
up to 98 %.
Communications labeled with this symbol have been judged by two referees as being “very important papers”.
Service
2874
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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Keywords
2972
Authors
2973
Preview
2975
Angew. Chem. Int. Ed. 2004, 43, 2868 – 2874
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