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Graphical Abstract Angew. Chem. Int. Ed. 482004

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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.
P. A. Troshin,* R. N. Lyubovskaya, I. N. Ioffe, N. B. Shustova,
E. Kemnitz, S. I. Troyanov*:
Synthesis and Structure of the Highly Chlorinated [60]Fullerene
C60Cl30 with Drum-Shaped Carbon Cage
DOI: 10.1002/anie.200461531
Published online: November 12, 2004
Y. Hu, G. Y. J. Chen, S. Q. Yao*:
Activity-Based High-Throughput Screening of Enzymes by Using
a DNA Microarray
DOI: 10.1002/anie.200461612
Published online: November 18, 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
Mol4D?Molecules in the Fourth
Dimension
E. Engel, M. Kruppa, B. Knig
6582
Chemical Micro-Process Engineering
Volker Hessel, Steffen Hardt, Holger L&we
reviewed by C. de Bellefon
6583
Biocatalysis
Andreas S. Bommarius, Bettina R. Riebel
reviewed by U. Bornscheuer
6584
An Introduction to Chemical Kinetics
Margaret Robson Wright
reviewed by D. Peeters
6585
http://www.cmbi.kun.nl/wetche/organic/
Books
Correspondence
Woodward?Hoffmann Rules
R. Hoffmann*
The well-known Woodward?Hoffmann
rules explain how the feasibility and
stereochemical outcome of pericyclic
reactions are governed by the symmetry
properties of the molecular orbitals of the
reactants and products. Triggered by a
recent claim by E. J. Corey, Roald Hoffmann recalls the first steps in the
development of this theory.
6586 ? 6590
A Claim on the Development of the
Frontier Orbital Explanation of
Electrocyclic Reactions
Essays
Chemistry in Literature
A. H. Hoveyda*
6592 ? 6594
In his book The Periodic Table, Primo Levi,
with touching thoughtfulness, sketched
the magic of the elements that make up
this world. As with all enduring works of
art, The Periodic Table is open to numerous interpretations. Another visit, a
quarter of a century after its publication,
proves to be most rewarding.
Primo Levi?s The Periodic Table. A Search
for Patterns in Times Past
6570
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
Angew. Chem. Int. Ed. 2004, 43, 6570 ? 6581
Angewandte
Chemie
Reviews
Noncovalent Interactions
D. H. Williams,* E. Stephens,
D. P. O?Brien, M. Zhou
6596 ? 6616
The strength lies within: This review
proposes that receptors and enzymes
(shown in blue in the scheme) derive an
important contribution to binding their
ligands and transition states (respec-
tively) by decreasing their dynamic behavior. Conversely, ligand binding energy is
reduced where the binding process
increases the dynamic behavior of the
receptor protein.
Understanding Noncovalent Interactions:
Ligand Binding Energy and Catalytic Efficiency from Ligand-Induced Reductions in
Motion within Receptors and Enzymes
Polymerization Catalysts
G. W. Coates,* D. R. Moore
Given the non-renewable nature of synthetic polymers from petroleum feedstocks, there is increasing interest in
developing routes to biodegradable polymeric materials from renewable resources. Polycarbonates made from CO2 and
epoxides (see scheme) have the potential
to meet these important goals. Reviewed
here are well-defined catalysts for epoxide?CO2 copolymerization and related
reactions.
6618 ? 6639
Discrete Metal-Based Catalysts for the
Copolymerization of CO2 and Epoxides:
Discovery, Reactivity, Optimization, and
Mechanism
Communications
Half-dissociated: Experimental and computational findings conclude that water
forms a highly ordered superstructure on
defect-free surfaces of zinc oxide, in which
every second water molecule is dissociated (see picture). The results are of
general relevance for heterogeneous
catalysis.
Angew. Chem. Int. Ed. 2004, 43, 6570 ? 6581
B. Meyer,* D. Marx, O. Dulub, U. Diebold,
M. Kunat, D. Langenberg,
C. W&ll*
6641 ? 6645
Partial Dissociation of Water Leads to
Stable Superstructures on the Surface of
Zinc Oxide
Single-Molecule Studies
Light switches: The photon capture area
of single fluorescent molecules has been
directly measured by switching them ?on
and off? with light. Stimulated emission of
single molecules (see picture) enables the
precise control of the excited state population probability of an individual molecule at room temperature.
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Meacham Ave., Elmont, NY 11003. Periodicals
Water Structure
L. Kastrup, S. W. Hell*
6646 ? 6649
Absolute Optical Cross Section of
Individual Fluorescent Molecules
postage paid at Jamaica NY 11431. US POSTMASTER: send address changes to Angewandte
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Postage and handling charges included. All
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2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
6571
Angewandte
Chemie
Giving cells some stick: Osteoblast
adhesion to titanium, a common material
for implants, is stimulated by coating with
an optimized and highly specific nonpeptidic ligand for the avb3 integrin (see
picture). This new technology is advantageous to conventional coating by peptides
or proteins in many practical aspects
(selectivity and activity, stability against
enzymatic degradation, sterilization,
costs).
Biomaterials
C. Dahmen, J. Auernheimer, A. Meyer,
A. Enderle, S. L. Goodman,
H. Kessler*
6649 ? 6652
Improving Implant Materials by Coating
with Nonpeptidic, Highly Specific Integrin
Ligands
Lewis Acids
Different octahedral units form the basis
of the structures of the very strong Lewis
acids aluminum bromide fluoride (ABF)
and aluminum chloride fluoride (ACF)
(see picture). A structure model for these
phases is established in which the octahedra are linked through m-bridging
fluorine atoms and m3-bridging X atoms
(X = Cl, Br). The bridging of three octahedra by a heavy halogen atom explains
the results of NMR and EXAFS analysis.
T. Krahl, E. Kemnitz*
6653 ? 6656
Amorphous Aluminum Bromide Fluoride
(ABF)
Markers by mass: The effect of terpenoids
on organisms can be investigated by
using DNA adducts as markers. Highresolution MS was used to characterize
DNA/a-pinene oxide adducts after enzymatic digestion. The reaction of a-pinene
oxide with the N7 position of guanosine
leads to cleavage of the N-glycosidic bond
and formation of the N7 guanine adducts
(see picture).
DNA Adducts
W. Schrader,* S. D&ring,
W. Joppek
6657 ? 6660
Mass Spectrometric Studies of DNA
Adducts from a Reaction with Terpenoids
Organocatalysis
J. W. Yang, M. T. Hechavarria Fonseca,
B. List*
6660 ? 6662
Impressive tolerance is displayed in the
efficient and chemoselective organocatalytic transfer hydrogenation of a,b-unsaturated aldehydes in the presence of a
Hantzsch dihydropyridine and a catalytic
Angew. Chem. Int. Ed. 2004, 43, 6570 ? 6581
amount of dibenzylammonium trifluoroacetate (see scheme). Various sensitive
functional groups such as the nitro,
cyano, alkenyl, and benzyloxy groups
survive these reaction conditions.
www.angewandte.org
A Metal-Free Transfer Hydrogenation:
Organocatalytic Conjugate Reduction of
a,b-Unsaturated Aldehydes
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
6573
Contents
Combinatorial Chemistry
M. Albrecht,* I. Janser, J. Runsink,
G. Raabe, P. Weis,
R. Fr&hlich
6662 ? 6666
Selecting Different Complexes from a
Dynamic Combinatorial Library of
Coordination Compounds
A choice selection: A dynamic combinatorial library of oligonuclear coordination
compounds is formed from a flexible
tris(catechol) ligand with titanium(iv)
ions in the presence of lithium carbonate
or potassium carbonate. A trinuclear
complex (1) can be isolated by crystallization from DMF. In contrast, welldefined mononuclear (2) compounds are
obtained by addition of Na+ as a template,
and tetranuclear compounds (3) are isolated by changing the solvent to DMSO.
Cyclizations
Small rings: Only a few methods are
known for the synthesis of cyclopropane
carbaldehydes and cyclopropyl ketones 2.
In a new, simple route to highly enantioenriched trisubstituted three-membered rings, 4-hydroxy-1-alkenyl N,N-diisopropyl carbamates 1 are treated with
NaH, resulting in migration of the carbamoyl group and intramolecular enolate
alkylation.
R. Kalkofen, S. Brandau, B. Wibbeling,
D. Hoppe*
6667 ? 6669
Synthesis of Stereohomogeneous Cyclopropanecarbaldehydes and Cyclopropyl
Ketones by Cycloalkylation of
4-Hydroxy-1-alkenyl Carbamates
Cyclopropanes
C. A. Risatti, R. E. Taylor*
6671 ? 6672
Enantioselective Synthesis of Cyclopropanes by Aldehyde Homologation
An efficient method for the enantioselective preparation of structurally diverse
cyclopropanes has been developed.
Sequential homoaldol coupling and acti-
Natural Products
The complex macrolide apoptolidinone
(1) was synthesized in 19 steps (longest
linear sequence) from (S)-malic acid. Key
reactions include A) two stereoselective
aldol reactions, B) a late-stage Grubbs
cross-metathesis reaction to install a
trisubstituted vinyl boronate, and C) an
intramolecular Suzuki?Miyaura reaction.
B. Wu, Q. Liu,
G. A. Sulikowski*
6673 ? 6675
Total Synthesis of Apoptolidinone
6574
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
vation steps result in a three-carbon
homologation of an aldehyde to give a
nonracemic, stereochemically rich cyclopropylcarboxaldehyde (see scheme).
Angew. Chem. Int. Ed. 2004, 43, 6570 ? 6581
Angewandte
Chemie
After all, neat As(N3)5 can be isolated: By
analogy with AsCl5, neat As(N3)5 was
predicted to be a highly unstable compound, and previous attempts at its
synthesis had resulted in intense explosions. The successful syntheses and
characterization of neat As(N3)5 and
Sb(N3)5 and the crystal structure of the
[Sb(N3)6] ion (see picture) are now
described.
Binary Group 15 Azides
R. Haiges,* J. A. Boatz, A. Vij, V. Vij,
M. Gerken, S. Schneider, T. Schroer,
M. Yousufuddin,
K. O. Christe*
6676 ? 6680
Polyazide Chemistry: Preparation and
Characterization of As(N3)5, Sb(N3)5, and
[P(C6H5)4][Sb(N3)6]
Carbohydrate Chemistry
A. Deleuze, C. Menozzi, M. Sollogoub,*
P. SinaQ*
6680 ? 6683
A rearrangement strategy was used for the
synthesis of a- and b-gem-difluorocarbad-glucose, which are close congeners of
a- and b-d-glucose, in which the endocyclic oxygen atom has been replaced by a
Synthesis of gem-Difluorocarba-d-glucose: A Step Further in Sugar Mimesis
gem-difluoromethylene group (see
scheme). The two anomers a or b were
obtained stereoselectively by the use of
steric or electronic control, respectively.
TIBAL = triisobutylaluminum.
Cluster Compounds
Hypervalency and secondary bonding are
the driving forces behind the rapid
absorption of gaseous carbon dioxide by
two organotellurium and organotin oxides
and the unexpected formation of a unique
tellurastannoxane cluster (see structure;
dark red Te, black Sn, gray C, light red O).
The absorption is reversible with the
liberation of carbon dioxide being
observed at temperatures between 90 and
145 8C.
J. Beckmann,* D. Dakternieks, A. Duthie,
N. A. Lewcenko, C. Mitchell 6683 ? 6685
Carbon Dioxide Fixation by the
Cooperative Effect of Organotin
and Organotellurium Oxides
Three terminal Sn=E bonds are present in
the imidotin clusters [(thf)LiSn3E3(m3NtBu)4] (E = Se, Te; see picture: N blue;
Sn gray; Te orange; Li purple; O red) that
are readily obtained under mild conditions, as solvent-separated ion pairs with
[Li(thf)4]+ (E = Se, Te) or [(thf)Li([12]crown-4)]+ counterions (E = Se), by
the reactions of the anionic cluster
[(thf)LiSn3(m3-NtBu)4] with the
appropriate chalcogen.
Angew. Chem. Int. Ed. 2004, 43, 6570 ? 6581
www.angewandte.org
Cluster Compounds
T. Chivers,* D. J. Eisler
6686 ? 6689
Complete Chalcogenation of Tin(ii)
Centers in an Imidotin Cluster
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
6575
Contents
Allylic Substitution
C.-W. Cho, M. J. Krische*
6689 ? 6691
Regio- and Stereoselective Construction
of g-Butenolides through PhosphineCatalyzed Substitution of Morita?Baylis?
Hillman Acetates: An Organocatalytic
Allylic Alkylation
Hold the metal: Upon exposure of acetates 1 to substoichiometric quantities of
triphenylphosphane in the presence of 2,
regioselective metal-free allylic substitu-
tion occurs through a formal tandem
SN2??SN2? substitution mechanism to
provide g-butenolides 3 with high levels of
regio- and diastereocontrol (see scheme).
Template-directed processes involving
polysaccharide, dextran, and preformed
zeolite crystals/nanoparticles are used to
prepare elaborate porous frameworks of
interconnected filaments of NaY zeolite/
silica nanoparticles, as well as macroscopic fibers of crystallographically
aligned silicalite nanocrystals (see picture; bar is 5 mm).
Nanotechnology
D. Walsh, A. Kulak, K. Aoki, T. Ikoma,
J. Tanaka, S. Mann*
6691 ? 6695
Preparation of Higher-Order Zeolite
Materials by Using Dextran Templating
Catch a falling star: Peptides from chiral,
Ca-methylated a-amino acids (see
scheme) found in l enantiomeric excess
in meteorites show diastereoselectivity
when reacting with racemic proteinogenic
amino acids. Accordingly, the prebiotic
soup of proteinogenic amino acids may
have evolved into a chirally unbalanced
system, eventually seeding the
homochirality of life.
Chirality
M. Crisma, A. Moretto, F. Formaggio,
B. Kaptein, Q. B. Broxterman,
C. Toniolo*
6695 ? 6699
Meteoritic Ca-Methylated a-Amino Acids
and the Homochirality of Life: Searching
for a Link
Cyclization
T. Hoshino,* K. Shimizu,
T. Sato
6700 ? 6703
Deletion of the Gly600 Residue of Alicyclobacillus acidocaldarius Squalene Cyclase
Alters the Substrate Specificity into that of
the Eukaryotic-Type Cyclase Specific to
(3S)-2,3-Oxidosqualene
6576
Removal service: A deletion mutant lacking the Gly600 residue of a prokaryotic
squalene?hopene cyclase was prepared.
Surprisingly, the mutant cyclase has no
enzyme activity for 1 and 3, but shows a
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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high conversion ratio for 2 (see scheme).
Deleting Gly600 alters the specificity from
prokaryotic into that of eukaryotic-type
cyclases.
Angew. Chem. Int. Ed. 2004, 43, 6570 ? 6581
Angewandte
Chemie
Strained Molecules
V. Ya. Lee, K. Takanashi, M. Ichinohe,
A. Sekiguchi*
6703 ? 6705
The First Bicyclo[1.1.0]butane Dianion of
Heavier Group 14 Elements
Carbon copies: Alkaline-earth metal (Mg,
Ca, and Sr) derivatives 2 of a silagermabicyclo[1.1.0]butane-2,4-diide are obtained
by the treatment of 1 with magnesium or
calcium in THF or by the reaction of the
dianion 3 with MgBr2, CaI2, or SrI2 in
THF. Such stable derivatives of charged
bicyclo[1.1.0]butanes have been elusive
species until now.
Porous Structures
Sifting through the surface: Permselective
core/shell microgels have been prepared
by using a labile cross-linker, which can be
cleaved stoichiometrically to control the
porosity of the shell. Proteins that are
smaller than the pore size are allowed to
permeate through the shell to bind with
the core-bound ligand (arrows; see picture).
S. Nayak, L. A. Lyon*
6706 ? 6709
Ligand-Functionalized Core/Shell
Microgels with Permselective Shells
During the biosynthesis of glycopeptide
antibiotics of the vancomycin family, several oxidative phenol coupling reactions
take place. An oxygenase (OxyB) from the
vancomycin producer catalyzes the first of
these coupling reactions to a significant
extent only when the putative hexapeptide
substrate is linked as a thioester to a
peptide carrier domain (PCD) derived
from the non-ribosomal peptide synthetase (see picture).
Enzyme Catalysis
K. Zerbe, K. Woithe, D. B. Li, F. Vitali,
L. Bigler, J. A. Robinson*
6709 ? 6713
An Oxidative Phenol Coupling Reaction
Catalyzed by OxyB, a Cytochrome P450
from the Vancomycin-Producing Microorganism
Carbenoid Reagents
M. Yan, N. Jacobsen, W. Hu,
L. S. Gronenberg, M. P. Doyle,* J. T. Colyer,
D. Bykowski
6713 ? 6716
Multiple C C bonds are formed in an
unprecedented reaction of an ylide with
2 equivalents of a rhodium-stabilized
carbene. The cascade cyclization of the
intermediate formed from the three components gives bicyclic pyrrolidine products with excellent diastereoselectivity
(see scheme).
O2 for you: The trans-m-1,2-peroxo Ni2
dimer 3, a structural motif unknown
previously in nickel coordination chemistry, was produced by reaction of the
(tmc)nickel(i) precursor 1 with O2. Thermal decomposition of 3 in CH3CN leads
to 2, in which the atoms of the hydroxide
ligand derive from O2 and the hydrocarbon solvent.
Angew. Chem. Int. Ed. 2004, 43, 6570 ? 6581
Stereoselective Synthesis of Bicyclic
Pyrrolidines by a Rhodium-Catalyzed
Cascade Process
Nickel Compounds
M. T. Kieber-Emmons, R. Schenker,
G. P. A. Yap, T. C. Brunold,
C. G. Riordan*
6716 ? 6718
Spectroscopic Elucidation of a Peroxo
Ni2(m-O2) Intermediate Derived from a
Nickel(i) Complex and Dioxygen
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2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
6577
Contents
Foldamer Structures
Independent of the ring size in the
aliphatic side chains, peptides made up of
b2,3-cyclic aminoxy acids, novel chiral
building blocks of foldamers, adopt uniform secondary structures consisting of
rigid b N O turns and 1.89-helix structures (see figure). This contrasts previous
results from other groups with cyclic ringconstrained b-peptides.
D. Yang,* D.-W. Zhang, Y. Hao, Y.-D. Wu,
S.-W. Luo, N.-Y. Zhu
6719 ? 6722
b2,3-Cyclic Aminoxy Acids: Rigid and RingSize-Independent Building Blocks of
Foldamers
Organocatalysis
I. K. Mangion, A. B. Northrup,
D. W. C. MacMillan*
6722 ? 6724
The Importance of Iminium Geometry
Control in Enamine Catalysis: Identification of a New Catalyst Architecture for
Aldehyde?Aldehyde Couplings
Central to the design of a new organocatalyst system for aldehyde?aldehyde aldol
reactions is the necessity of iminium
geometry control during the enamine
addition step (see scheme). Significant
Supramolecular Structures
J. R. Nitschke,* M. Hutin,
G. Bernardinelli
Spring-loaded supramolecular chemistry:
Pyridine-2-carboxaldehyde reacts with the
m-phenylenediamine shown in aqueous
solution in the presence of CuI ions to give
a tetracopper(i) grid complex (see structure). This structure is stable in water, but
not in any of the organic solvents tried.
The strain incorporated into the structure
is compensated by a diffuse pressure
applied by the hydrophobic effect.
R = 2-hydroxyethylcarbamoyl.
6724 ? 6727
The Hydrophobic Effect as a Driving Force
in the Self-Assembly of a [2 R 2] Copper(i)
Grid
Peptide Structures
S. Aravinda, S. Datta, N. Shamala,*
P. Balaram*
6728 ? 6731
Hydrogen-Bond Lengths in Polypeptide
Helices: No Evidence for Short Hydrogen
Bonds
6578
structural variation in both the aldol donor
and aldol acceptor are possible while
maintaining high reaction efficiency and
enantioselectivity. TFA = trifluoroacetic
acid.
The long and the short of it: NиииO
distances less than 2.8 T (see picture)
have been implicated in determining the
220 nm circular dichroism band intensity
in helical peptides. An analysis of helical
peptide crystal structures, however,
reveals the average experimentally determined hydrogen-bond lengths are 2.978?
3.113 T (a helix) and 2.907?3.211 T
(310 helix).
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
Angew. Chem. Int. Ed. 2004, 43, 6570 ? 6581
Angewandte
Chemie
Water-soluble chiral Ru complexes with a
b-cyclodextrin unit have been shown to
catalyze the reduction of aliphatic ketones
(see scheme) with up to 97 % ee and in
good to excellent yields in the presence of
sodium formate. The b-cyclodextrin unit is
an essential component of the catalyst. It
contributes to the unprecedented levels of
enantioselectivity observed through the
preorganization of the substrates in the
hydrophobic cavity.
Asymmetric Reduction
A. Schlatter, M. K. Kundu,
W.-D. Woggon*
6731 ? 6734
Enantioselective Reduction of Aromatic
and Aliphatic Ketones Catalyzed by
Ruthenium Complexes Attached to
b-Cyclodextrin
A new twist of RNA fate: Site-selective
chemical functionalization at the C2?? OH
group of paromomycin (1) afforded a
novel analogue with potent inhibitory
activity against several bacterial strains,
including a multidrug-resistant S. aureus
(MRSA) strain. X-ray cocrystal-structure
determination of the complex with the
A site of E. coli RNA revealed a new mode
of binding in which significant conformational and positional changes had taken
place in rings III and IV.
Drug Design
Protecting group chemistry was used to
functionalize the channel entrances of
zeolite L crystals. This approach is broadly
applicable and can be used to obtain a
wide range of new zeolite-based materials.
The picture shows two microcrystals
modified with amino groups at the channel entrances, which reacted further with a
red-luminescent head molecule.
FG = functionalizing group, prot. = protector.
Modified Zeolites
B. FranUois, J. Szychowski, S. S. Adhikari,
K. Pachamuthu, E. E. Swayze, R. H. Griffey,
M. T. Migawa, E. Westhof,*
S. Hanessian*
6735 ? 6738
Antibacterial Aminoglycosides with a
Modified Mode of Binding to the
Ribosomal-RNA Decoding Site
S. Huber, G. Calzaferri*
6738 ? 6742
Sequential Functionalization of the
Channel Entrances of Zeolite L Crystals
Cluster Compounds
M. L. Kuhlman,
T. B. Rauchfuss*
Get into shape under redox: Rearrangement of [Ru4S3(arene)4] accompanies
redox processes and occurs in its
reduction of H+ to H2 (see scheme;
Angew. Chem. Int. Ed. 2004, 43, 6570 ? 6581
Ru = Ru(cymene)). The [Ru4S3(arene)4]2+
ion is so crowded that arene rotation is
hindered, which allows the detection of
atropisomers.
www.angewandte.org
6742 ? 6745
Competing H H, S S, and M M Bond
Formation in the ?Shape-Shifting? Cluster
[Ru4S3(arene)4]2+
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
6579
Contents
Electron Microscopy
J. M. Thomas,* P. A. Midgley,*
T. J. V. Yates, J. S. Barnard, R. Raja,
I. Arslan, M. Weyland
6745 ? 6747
The Chemical Application of HighResolution Electron Tomography:
Bright Field or Dark Field?
Visualizing 3D structures (especially of
supported catalysts) by the nondestructive method of electron tomography is
best accomplished by high-angle annular
dark-field (HAADF) rather than by brightfield (BF) imaging; bimetallic clusters of
[Ru10Pt2] (diameter ca. 0.4 nm), supported
on nanoporous silica, are invisible in BF
but readily visible in HAADF images (see
pictures).
Host?Guest Systems
D. Fiedler, R. G. Bergman,*
K. N. Raymond*
Catalytic containers: A supramolecular
metal?ligand assembly [M4L6] is utilized
as a catalytic host for the unimolecular
carbon?carbon bond-forming rearrangement of enammonium cations (see
scheme). The restricted reaction space of
the supramolecular structure forces the
substrate to adopt a reactive conformation upon binding to the interior. The
assembly achieves up to 850-fold rate
acceleration of the rearrangement.
6748 ? 6751
Supramolecular Catalysis of a Unimolecular Transformation: Aza-Cope Rearrangement within a Self-Assembled Host
Communications labeled with this symbol have been judged by two referees as being ?very important papers?.
Service
Keywords
6752
Authors
6753
Angewandte?s
Sister Journals
6580
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
6754 ? 6755
Index
6759
Preview
6827
Angew. Chem. Int. Ed. 2004, 43, 6570 ? 6581
Angewandte
Chemie
Corrigendum
*
We have become aware of a report by Bergman and co-workers that the abstraction of a
methyl group from [Cp2ZrMe2] with B(C6F5)3 leads to an acceleration of the intramolecular hydroamination reaction of an aminoallene substrate relative to the reaction
in which only [Cp2ZrMe2] is used (L. Ackermann, R. G. Bergman, R. N. Loy, J. Am.
Chem. Soc. 2003, 125, 11 956). We therefore correct our statement on p. 5543 that ?alkyl
metallocene cations have been used in organic synthesis, but to the best of our
knowledge not in hydroamination reactions?, with reference to the above-mentioned
publication.
Hydroamination/Cyclization of
Aminoalkenes Using Cationic
Zirconocene and Titanocene Catalysts**
K. C. Hultzsch,*
D. V. Gribkov
5542-?5546
Angew. Chem. Int. Ed. 2004, 43
DOI 10.1002/anie.200460880
Building Molecular Minerals: All Ferric
Pieces of Molecular Magnetite
In the legends to the Figures 3 and 4 the sweep rates and temperatures have been
transposed. The correct values are as follows:
Figure 3: sweep rate 0.001 Ts
T = 0.01?0.5 K.
1
and T = 0.04?0.5 K; Figure 4: sweep rate 0.007 Ts
1
and
G. W. Powell, H. N. Lancashire,
E. K. Brechin,* D. Collison,* S. L. Heath,*
T. Mallah, W. Wernsdorfer
5772?5775
The authors apologize for the error.
Angew. Chem. Int. Ed. 2004, 43
DOI 10.1002/anie.200460636
Angew. Chem. Int. Ed. 2004, 43, 6570 ? 6581
www.angewandte.org
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
6581
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