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Graphical Abstract Angew. Chem. Int. Ed. 272006

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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:
A. Abo-Riziq, B. Crews, M. Callahan, L. Grace, M. de Vries*
Spectroscopy of Isolated Gramicidin Peptides
C. Ye,* Y. Bando, G. Shen, D. Golberg
Formation of Single-Crystalline SrAl2O4 Nanotubes by a Roll-Up
and Post-Annealing Approach
A. Narayanaswamy, H. Xu, N. Pradhan, X. Peng*
Single-Crystal Nanoflowers with Different Chemical
Compositions and Physical Properties Grown by Limited Ligand
Protection
A. Tao, P. Sinsermsuksakul, P. Yang*
Polyhedral Silver Nanocrystals with Distinct Scattering
Signatures
J. van Bokhoven*, C. Louis, J. Miller, M. Tromp, O. Safonova,
P. Glatzel
Activation of Oxygen on Gold-Alumina Catalysts: In Situ
High-Energy Resolution Fluorescence and Time-Resolved X-ray
Spectroscopy
M. Brynda, R. Herber,* P. Hitchcock, M. Lappert,* I. Nowik,
P. Power,* A. Protchenko, A. Ruzicka, J. Steiner
Higher Nuclearity Group 14 Metalloid Clusters: [Sn9{Sn(NRR’)}6]
(R = 2,6-iPr2C6H3 ; R’ = SiMe3 or SiMe2Ph)
Meeting Reviews
Functional Molecular Assemblies
J. A. Thomas
4396
Books
Nanoparticle Assemblies and
Superstructures
Nicholas A. Kotov
reviewed by M. Brust
4399
Biofunctionalization of Nanomaterials
Nanotechnologies for the Life Sciences,
Vol. 1
Challa Kumar
reviewed by G. Wittstock
4400
Highlights
Hypervalent Iodine Compounds
R. D. Richardson, T. Wirth*
4402 – 4404
Hypervalent Iodine Goes Catalytic
4386
A dash of iodine: Different reactions
relying on the power of hypervalent iodine
reagents can now be performed with
catalytic amounts of these compounds
and a stoichiometric oxidant. Oxidations
of alcohols, a-functionalizations of
ketones, and spirocyclizations of phenol
derivatives are possible.
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Angew. Chem. Int. Ed. 2006, 45, 4386 – 4394
Angewandte
Chemie
Essays
Biosynthesis
A. R. Gallimore,
J. B. Spencer*
4406 – 4413
Stereochemical Uniformity in Marine
Polyether Ladders—Implications for the
Biosynthesis and Structure of Maitotoxin
Odd one out: Marine polyether ladders
are probably the most well-known of all
marine natural products, not only for their
fascinating structures, but also for their
characteristic toxicity. A very straightforward model for the biosynthesis of all
known polyether ladders, including
maitotoxin (the largest and most toxic of
this structural family; see formula) is
described, but is the structure of this giant
molecule really known?
Reviews
Balance control: Kinetically controlled
cyclooligomerization is impeded by the
formation of higher oligomers (“overshooting”). Under reversible conditions,
the product distribution is determined by
the thermodynamic stability, which is
balanced by both entropic and enthalpic
factors. Methods based on dynamic
covalent chemistry and the use of the
energy gap principle enable the formation
of target macrocycles by cyclooligomerization to be controlled.
Macrocycle Synthesis
W. Zhang, J. S. Moore*
4416 – 4439
Shape-Persistent Macrocycles: Structures
and Synthetic Approaches from Arylene
and Ethynylene Building Blocks
Communications
Nanobiotechnology
A. Kurz, A. Bunge, A.-K. Windeck, M. Rost,
W. Flasche, A. Arbuzova, D. Strohbach,
S. M7ller, J. Liebscher,* D. Huster,*
A. Herrmann*
4440 – 4444
Anchoring for DNA: A lipophilic oligonucleotide consisting of 21 thymidine units
and two lipophilic nucleotides L was synthesized and bound to vesicular surfaces
(see fluorescence image). The membranebound oligonucleotide binds comple-
mentary DNA strands by formation of
Watson–Crick base pairs. The lipidanchored oligonucleotide is preferentially
enriched in liquid-disordered membrane
domains.
For the USA and Canada:
ANGEWANDTE CHEMIE International
Edition (ISSN 1433-7851) is published weekly
by Wiley-VCH PO Box 191161, D 69451 Weinheim, Germany. Air freight and mailing in the
USA by Publications Expediting Inc. 200
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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$ 5685/5168 (valid for print and
Angew. Chem. Int. Ed. 2006, 45, 4386 – 4394
Lipid-Anchored Oligonucleotides for
Stable Double-Helix Formation in Distinct
Membrane Domains
electronic / print or electronic delivery); for
individuals who are personal members of a
national chemical society prices are available
on request. Postage and handling charges
included. All prices are subject to local VAT/
sales tax.
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
4387
Angewandte
Chemie
Enantiomer or racemate? For compound
1 this question can be answered with one
glance. Racemic starting material forms
the meso form of 1 with the expected UV/
Vis spectra of the chromophore, whereas
the enantiomeric compounds display
color shifts and large CD effects indicative
of strong intramolecular exciton interactions.
Exciton Interactions
Opposites attract: The compounds [(h5C5Me5)2Ln Al(h5-C5Me5)] (Ln = Eu, Yb;
see scheme) represent the first compounds with a bond between aluminum
and a 4f metal. The bonds are predominantly electrostatic with insignificant
charge-transfer and covalent contributions.
Metal–Metal Interactions
H. Langhals,* O. Krotz
4444 – 4447
Chiral, Bichromophoric Silicones:
Ordering Principles of Structural Units in
Complex Molecules
M. T. Gamer, P. W. Roesky,*
S. N. Konchenko, P. Nava,
R. Ahlrichs
4447 – 4451
Al Eu and Al Yb Donor–Acceptor Bonds
Pattern Formation in Crystals
T. X. Wang, A.-W. Xu,*
H. CNlfen*
Intelligent design? Depending on the
starting pH, ultralong nanofibers (see
picture; left) or patterns of concentric
circles (right) are produced in the polymer-controlled crystallization of BaCO3.
The ring patterns are the first examples of
nanoparticle self-organization that can be
described by a Belousov–Zhabotinsky
formalism.
4451 – 4455
Formation of Self-Organized Dynamic
Structure Patterns of Barium Carbonate
Crystals in Polymer-Controlled
Crystallization
NMR Methods
C. M. Thiele,* A. Marx, R. Berger, J. Fischer,
M. Biel, A. Giannis
4455 – 4460
Determination of the Relative
Configuration of a Five-Membered
Lactone from Residual Dipolar Couplings
syn- or anti-pathy? Determination of the
relative configuration of the a-methyleneg-butyrolactone 1 failed by conventional
NMR methods, because structures in the
conformational space of both diastereo-
Angew. Chem. Int. Ed. 2006, 45, 4386 – 4394
isomers exist that fulfill the restraints
from NOE and 3J coupling data equally
well. Homo- and heteronuclear residual
dipolar couplings were measured which
indicate that 1 is trans configured.
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
4389
Contents
Theoretical Chemistry
S. Grimme*
4460 – 4464
Seemingly Simple Stereoelectronic Effects
in Alkane Isomers and the Implications
for Kohn–Sham Density Functional Theory
A theoretical disaster: In contrast to
general opinion, modern density functional methods are not able to even
qualitatively describe the overall energetics of simple alkylation reactions (see
Solid-State Structures
M. F. BrQu, A. Pfitzner*
scheme). The main reason is that the
currently used hybrid functionals almost
completely neglect the generally relevant
electron correlation effects for mediumrange electron–electron distances.
Unrattled cage: From the reaction of HgI2,
As, and S, an adduct of linear HgI2 units
and undistorted As4S4 cages is formed
with only weak intermolecular interactions
(see picture; Hg gray, I violet, S yellow,
As blue). For the first time in this class of
compounds, no polycationic network of
Hg and S atoms is obtained. The optimization of the total energy prevents the
formation of Hg S bonds and the cleavage of the As4S4 cage.
4464 – 4467
HgI2·As4S4 : An Adduct from HgI2
Molecules and Undistorted As4S4 Cages
Metal-Free Heterogeneous Catalysis
In the footsteps of Liebig and Berzelius: A
material first synthesized in 1834, carbon
nitride (C3N4), was synthesized in a
graphitic mesoporous form by using silica
nanoparticles as templates. The resulting
electron-rich solid is an active catalyst for
the Friedel–Crafts acylation of benzene
with hexanoyl chloride. Presumably the
catalysis arises from a shift of electron
density from the MOs of the catalyst to
the unoccupied orbitals of benzene (see
picture).
F. Goettmann, A. Fischer, M. Antonietti,
A. Thomas*
4467 – 4471
Chemical Synthesis of Mesoporous
Carbon Nitrides Using Hard Templates
and Their Use as a Metal-Free Catalyst for
Friedel–Crafts Reaction of Benzene
Synthetic Methods
I. Nakamura,* T. Sato,
Y. Yamamoto
4473 – 4475
Gold-Catalyzed Intramolecular
Carbothiolation of Alkynes: Synthesis of
2,3-Disubstituted Benzothiophenes from
(a-Alkoxy Alkyl) (ortho-Alkynyl Phenyl)
Sulfides
4390
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Gold forms rings: AuCl-catalyzed cyclization of (a-alkoxy alkyl) (ortho-alkynyl
phenyl) sulfides 1 proceeds under mild
conditions to give 3-(a-alkoxy alkyl) benzothiophenes 2 in high yields for a wide
range of substrates (see scheme). The
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
starting materials are readily available
through acetalization of ortho-bromobenzenethiol and subsequent Sonogashira
coupling. This methodology provides an
atom-economic route to sulfur-containing
heteroarenes.
Angew. Chem. Int. Ed. 2006, 45, 4386 – 4394
Angewandte
Chemie
Asymmetric Epoxidation
C. P. Burke, Y. Shi*
Putting the O into olefins: A highly regioand enantioselective epoxidation of conjugated dienes was developed using glu-
cose-derived ketone 1 as catalyst and
oxone (KHSO5) as oxidant to form vinyl
cis-epoxides (see scheme).
Spaced out: Single-walled carbon nanotubes (SWNTs) with covalently linked
tetrathiafulvalene (TTF) derivatives have
been synthetized and fully characterized
as potential donor–acceptor nanoconjugates. Near-infrared flourescence and
transient absorption measurements
showed that the charge recombination
dynamics is a function of the spacer
linking the two moieties and the donor
ability of the different TTF derivatives.
Staying active: The title method allows
continuous and controlled polymerization
with significantly less Cu catalyst than is
required for conventional atom-transfer
radical polymerization (as low as
10 3 mol % vs. monomer). The CuI activator is constantly regenerated by a
reducing agent, which compensates for
any loss of CuI as a result of radical
termination reactions (see scheme).
Which bonds bind better? According to
NMR experiments with the alkane complex [CpRe(CO)2(cyclohexane)] at low
temperatures, complexation with an axial
proton is preferred over that through an
equatorial one by about 1.5 kJ mol 1. Calculations support this order of binding
energies. The preference is proposed to be
due to stronger electron donation through
hyperconjugation from a C H bond than
from a C C bond.
Angew. Chem. Int. Ed. 2006, 45, 4386 – 4394
4475 – 4478
Regio- and Enantioselective Epoxidation
of Dienes by a Chiral Dioxirane: Synthesis
of Optically Active Vinyl cis-Epoxides
Donor–Acceptor Systems
M. S. Herranz, N. MartTn,* S. Campidelli,
M. Prato,* G. Brehm,
D. M. Guldi*
4478 – 4482
Control over Electron Transfer in
Tetrathiafulvalene-Modified Single-Walled
Carbon Nanotubes
Controlled Radical Polymerization
W. Jakubowski,
K. Matyjaszewski*
4482 – 4486
Activators Regenerated by Electron
Transfer for Atom-Transfer Radical
Polymerization of (Meth)acrylates and
Related Block Copolymers
Alkane Ligands
D. J. Lawes, T. A. Darwish, T. Clark,*
J. B. Harper,* G. E. Ball*
4486 – 4490
A Rhenium–Cyclohexane Complex with
Preferential Binding of Axial C H Bonds:
A Probe into the Relative Ability of C H,
C D, and C C Bonds as
Hyperconjugative Electron Donors?
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
4391
Contents
Cyclophane Structure and Behavior
Spreading the charge: The highly stable
dimeric radical cation of a C3-symmetric
triazacyclophane (see picture), with the
positive charge delocalized over the two
molecules, offers an excellent model for
the study of intermolecular communication depending on hole hopping.
B. GVmez-Lor,* G. Hennrich, B. Alonso,
A. Monge, E. Gutierrez-Puebla,
A. M. Echavarren*
4491 – 4494
A Redox-Active C3-Symmetric TriindoleBased Triazacyclophane
Synchronized Motion of Ligands
R. Romeo,* S. Carnabuci, L. Fenech,
M. R. Plutino, A. Albinati
4494 – 4498
Overcrowded Organometallic
Platinum(II) Complexes That Behave as
Molecular Gears
In gear: Dynamic 1H NMR studies on
some organometallic platinum(II) compounds reveal a synchronism between
rotation around the Pt P bond and the
oscillation of a phenanthroline ligand
between two nonequivalent exchanging
sites. The system behaves as a molecularsized analogue of a mechanical gear (see
picture; C gray, N blue, O red, P purple)
whose dynamic properties can be tuned
through small structural changes.
Sulfur–Chromium Complex
Diamagnetic p complexes are formed in
the reaction between [{CpCr(CO)3}2] and
dithiadiazolyl dimers [S2N2CR]2 (R = substituted phenyl rings) in which the
heterocycles are h2-coordinated to the
metal in endo (depicted) or exo fashion.
The isomers interconvert in solution at
room temperature. These complexes are
remarkable for retaining intact the S S
bonds of the dithiadiazolyl radicals
(C gray, H white, O red, Cr purple, S yellow, N blue, Cl green).
H. F. Lau, V. W. L. Ng, L. L. Koh, G. K. Tan,
L. Y. Goh,* T. L. Roemmele,
S. D. Seagrave, R. T. BoerW* 4498 – 4501
Cyclopentadienylchromium Complexes of
1,2,3,5-Dithiadiazolyls: h2 p Complexes of
Cyclic Sulfur–Nitrogen Compounds
Cross-Coupling Reactions
B. Alcaide,* P. Almendros,*
T. MartTnez del Campo
4501 – 4504
Reaction of Two Different a-Allenols
in a Heterocyclization/Cross-Coupling
Sequence: Convenient Access to
Functionalized Buta-1,3-dienyl
Dihydrofurans
4392
www.angewandte.org
In a single step a highly functionalized
buta-1,3-dienyl-substituted 2,5-dihydrofuran unit can be formed from two
different a-allenol derivatives through a
novel heterocyclization/cross-coupling
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
sequence (see scheme). The reactions are
fast and totally chemo- and regioselective:
No homocoupling products or heterocycles other than the five-membered oxacycle are formed.
Angew. Chem. Int. Ed. 2006, 45, 4386 – 4394
Angewandte
Chemie
N,P Clathrates
A new structure type, predicted as a
possible candidate clathrasil structure, is
exhibited by P4N4(NH)4(NH3), which is
the first microporous nitridic clathrate
(see picture; blue N, pink P, dark gray H).
P4N4(NH)4(NH3) was synthesized at
11 GPa and 600 8C, and its crystal structure was determined by powder X-ray
diffraction. The presence of intercalated
ammonia was verified by mass chromatography and IR spectroscopy.
F. Karau, W. Schnick*
A Nitridic Clathrate: P4N4(NH)4(NH3)
Tubular balls: Self-assembly of an Au
nanocluster with bionanotubes of bacteriophage T4 gene product 5 (gp5) trimers
has been demonstrated (see picture). The
triad of His6 fragments at the C terminus
of (gp5–His6)3 contributed to the construction of an ordered tetrapod-like bionanotube assembly and the formation of
Au nanoclusters with uniform size distribution.
Angew. Chem. Int. Ed. 2006, 45, 4386 – 4394
4505 – 4508
Nanocluster Assembly
T. Ueno,* T. Koshiyama, T. Tsuruga,
T. Goto, S. Kanamaru, F. Arisaka,
Y. Watanabe*
4508 – 4512
Bionanotube Tetrapod Assembly by In
Situ Synthesis of a Gold Nanocluster with
(Gp5–His6)3 from Bacteriophage T4
A chip for single mismatches: Results
obtained with a photochemical-ligationbased DNA chip for enhanced discrimination of single-nucleotide polymorphisms (see scheme) show that the reaction
takes place over a period of hours, with
the 50 % stage reached within 10 minutes.
A single mismatch in the target sequence
yielded extremely little ligated product (a
rate 103-fold lower than for the complementary case).
DNA Recognition
Resistance is useful: A thiazyl-radical salt,
[NT]3[GaCl4] (see structural diagram),
exhibits negative resistance (see graph) in
a charge-ordered state of the square
columnar network of NT molecules. As the
negative-resistance effect is observed at
low electrical fields and high temperatures
(290 K), it is potentially attractive for
applications such as electrical devices.
Electron Transport
S. Ogasawara, K. Fujimoto* 4512 – 4515
SNP Genotyping by Using Photochemical
Ligation
K. Okamoto, T. Tanaka, W. Fujita,
K. Awaga,* T. Inabe
4516 – 4518
Low-Field Negative-Resistance Effect in a
Charge-Ordered State of Thiazyl-Radical
Crystals
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
4393
Contents
Directed Evolution
Changing its nature: Global incorporation
of noncanonical amino acids can alter the
behavior of proteins in useful ways. In
some cases, however, replacement of
natural amino acids by noncanonical
analogues (blue bars in picture) can cause
loss of protein stability. After several
generations, functional proteins of nonnatural composition were prepared
through residue-specific incorporation
combined with directed evolution.
J. K. Montclare, D. A. Tirrell* 4518 – 4521
Evolving Proteins of Novel Composition
Service
Keywords
4522
Authors
4523
Preview
4525
For more information on
ChemMedChem see
www.chemmedchem.org
4394
www.angewandte.org
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Angew. Chem. Int. Ed. 2006, 45, 4386 – 4394
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