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Graphical Abstract Angew. Chem. Int. Ed. 122005

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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:
Kendric J. Nelson, Ian D. Giles, William W. Shum, Atta M. Arif,
Joe S. Miller*
The Myth of Cyanide Always Being a Strong Field Ligand:
Synthesis and Structural Characterization of Homoleptic S = 2
Pentacyanochromate(II), [CrII(CN)5]3 and
Nonacyanodichromate(II), [CrII2(CN)9]5
Andrew J. Wilson, Mitsutoshi Masuda, Rint P. Sijbesma,*
E. W. Meijer*
Chiral Amplification in the Transcription of Supramolecular
Helicity into a Polymer Backbone
Sang Hyuk Im, Yun Tack Lee, Benjamin Wiley, Younan Xia*
Large-Scale Synthesis of Silver Nanocubes: The Role of HCl in
Promoting Cube Perfection and Monodispersity
Sridhar Narayan, John Muldoon, M. G. Finn, Valery V. Fokin,
Hartmuth C. Kolb, K. Barry Sharpless*
“On Water”: Unique Reactivity of Organic Compounds in
Aqueous Suspensions
Tetsuro Murahashi, Christopher R. Clough, Joshua S. Figueroa,
Christopher C. Cummins*
A Ligand Comprised of Dinitrogen and
Methyldiphenylphosphine in a Cationic Molybdenum Complex
Mark Gandelman, Eric N. Jacobsen*
Highly Enantioselective Catalytic Conjugate Addition of
N Heterocycles to a,b-Unsaturated Ketones and Imides
Obituary
W. Burchard
Walter Hugo Stockmayer (1914–2004): Macromolecules
1754 – 1755
Books
Kinetic Processes
Kenneth A. Jackson
reviewed by A. G. Munoz
1756
Energy Landscapes
David J. Wales
reviewed by A. Heuer
1756
Acid treatment: Exposure of catalytically
inactive (neutral) molecules to strong
Brønsted acids generates cationic species
(e.g. 1 and 2) that catalyze a wide range of
synthetically powerful transformations.
These reactions give products with excellent ee values. TfO = trifluoromethanesulfonate; TFA = trifluoroacetic acid.
Highlights
Organocatalysis
C. Bolm,* T. Rantanen, I. Schiffers,
L. Zani
1758 – 1763
Protonated Chiral Catalysts: Versatile
Tools for Asymmetric Synthesis
1744
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
Angew. Chem. Int. Ed. 2005, 43, 1744 – 1752
Angewandte
Chemie
Reviews
Recognising recognition: In describing
intermolecular recognition, conventional
wisdom often relies on weak bonds
between individual atoms in different
molecules, rather than considering lesslocalized interactions between molecular
electron densities (see picture). A proposal is made to abandon the traditional
view of a molecule as an array of atoms, in
favor of an electron-cloud picture. The
new computational tool pixel is used to
calculate the intermolecular energies from
the electron density of the isolated molecules.
Intermolecular Bonding
Types and structural features of noncovalent, multipolar interactions between
intrinsically polar molecular functional
groups are analyzed by using crystallographic-database mining. The results are
discussed on the basis of scatterplot
correlations of geometrical parameters.
The picture shows a section of a complex
of human transthyretin with flufenamic
acid which displays three noncovalent
polar CF···C=O contacts.
Molecular Recognition
J. D. Dunitz,*
A. Gavezzotti*
1766 – 1787
Molecular Recognition in Organic
Crystals: Directed Intermolecular Bonds
or Nonlocalized Bonding?
R. Paulini, K. Mller,*
F. Diederich*
1788 – 1805
Orthogonal Multipolar Interactions in
Structural Chemistry and Biology
Communications
Luminescent Assemblies
Red, white, and blue: White light was
obtained by partial energy transfer (@ET)
between a blue-emitting IrIII–phenylpyridine complex and a red-emitting EuIII–
terpyridine chelate through excitation of
the assembly that is formed from the two
metal complexes (see picture).
For the USA and Canada:
ANGEWANDTE CHEMIE International
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USA by Publications Expediting Inc. 200
Meacham Ave., Elmont, NY 11003. Periodicals
Angew. Chem. Int. Ed. 2005, 43, 1744 – 1752
P. Coppo, M. Duati, V. N. Kozhevnikov,
J. W. Hofstraat, L. De Cola* 1806 – 1810
White-Light Emission from an Assembly
Comprising Luminescent Iridium and
Europium Complexes
postage paid at Jamaica NY 11431. US POSTMASTER: send address changes to Angewandte
Chemie, Wiley-VCH, 111 River Street, Hoboken,
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and electronic / print or electronic delivery); for
individuals who are personal members of a
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Postage and handling charges included. All
Wiley-VCH prices are exclusive VAT.
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
1745
Angewandte
Chemie
Stacking Interactions
Metal-hinged, organic-pillared cages
accommodate a limited number (n) of
p-stacked molecules in the cavity (see
scheme): Discrete n + 2 aromatic stacking
occurs by the accommodation of n large
aromatic guests (n = 1–3). Owing to efficient donor–acceptor (D–A) interactions,
A–D–A (n = 1), A–D–D–A (n = 2), and A–
D–A–D–A (n = 3) stacks are observed,
which bring about even–odd-number
effects in the UV/Vis absorption spectra.
M. Yoshizawa, J. Nakagawa, K. Kumazawa,
M. Nagao, M. Kawano, T. Ozeki,
M. Fujita*
1810 – 1813
Discrete Stacking of Large Aromatic
Molecules within Organic-Pillared
Coordination Cages
Cell Imaging
S. Aime,* C. Carrera, D. Delli Castelli,
S. Geninatti Crich,
E. Terreno
1813 – 1815
Cell-tracking experiments by MRI are
possible with a novel class of Tb and Eu
paramagnetic imaging agents, with which
contrast is generated upon irradiation at a
specific frequency (see picture). Middle:
A) unlabeled; B) Tb-labeled; C) Eulabeled; D) Tb- and Eu-labeled cells. Left:
irradiation at 180 kHz (Tb-agent-specific). Right: irradiation at 15 kHz (Euagent-specific).
Molecular gas jars: Methane and carbon
dioxide can be stored in open-pore
van der Waals crystals of tris-o-phenylenedioxycyclotriphosphazene at low partial
pressure, whereas hydrogen, nitrogen,
and oxygen are selectively excluded. Gas
molecules participate in the supramolecular network of weak interactions and
reside in the tight nanochannels in close
contact with the surrounding aromatic
rings (see picture).
Inclusion Compounds
P. Sozzani,* S. Bracco, A. Comotti,
L. Ferretti, R. Simonutti
1816 – 1820
Methane and Carbon Dioxide Storage in a
Porous van der Waals Crystal
Surface Chemistry
Chiral control without chirality: The
adsorption of achiral liquid-crystal molecules to graphite substrates can generate
surfaces with controlled enantiomeric
excess and absolute chirality in the presence of a magnetic field, which assists in
orienting the molecules. Unlike conventional approaches for chiral control, no
chiral inputs are needed.
Angew. Chem. Int. Ed. 2005, 43, 1744 – 1752
Tunable Imaging of Cells Labeled with
MRI-PARACEST Agents
A. M. Berg, D. L. Patrick*
1821 – 1823
Preparation of Chiral Surfaces from
Achiral Molecules by Controlled
Symmetry Breaking
www.angewandte.org
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
1747
Contents
Heterogeneous Catalysis
I. N. Remediakis,* N. Lopez,
J. K. Nørskov
1824 – 1826
CO Oxidation on Rutile-Supported Au
Nanoparticles
What makes inert gold active? The answer
lies in controlling the structure of Au
particles at the nanoscale: Either many
interface sites or many low-coordinate Au
atoms need to be present in the particles.
This principle is demonstrated by modeling the oxidation of CO on a rutile (TiO2)supported Au nanocluster, the transition
state of which does not involve the titania
support (see picture: Au yellow, Ti light
gray, C dark gray, O red).
Heterogeneous Catalysis
A team effort: Mesoporous silica nanosphere (MSN) materials bifunctionalized
with a general acid group and a base
group in various relative concentrations
are described and shown to function as
cooperative catalytic systems. The turnover numbers observed indicate that the
acid groups can activate substrates in
cooperation with the base groups to
catalyze reactions that involve carbonyl
activation (see picture).
S. Huh, H.-T. Chen, J. W. Wiench,
M. Pruski, V. S.-Y. Lin*
1826 – 1830
Cooperative Catalysis by General Acid and
Base Bifunctionalized Mesoporous Silica
Nanospheres
Surface Chemistry
A. Mulligan, I. Lane, G. B. D. Rousseau,
S. M. Johnston, D. Lennon,
M. Kadodwala*
1830 – 1833
Going Beyond the Physical: Instilling
Chirality onto the Electronic Structure of a
Metal
Look below the surface: An adsorbed
chiral molecule, 1-(1-naphthyl)ethylamine, reversibly instills chirality onto the
electronic structure of a copper surface
(see picture), a previously unobserved
phenomenon. Conveying chirality onto
the electronic structure of a metal surface
is a possible mechanism by which chemical reactivity and electrical properties
may be made chirally dependent.
Self-Assembled Nanoparticles
L.-s. Li, S. I. Stupp*
Good as gold: Nanofibers with surface
hydrogen-bonding motifs co-assembled
from peptide-based amphiphilic molecules were used to template one-dimensional assemblies of preformed lipophilic
inorganic nanoparticles in apolar organic
solvents (see figure).
1833 – 1836
One-Dimensional Assembly of Lipophilic
Inorganic Nanoparticles Templated by
Peptide-Based Nanofibers with Binding
Functionalities
1748
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
Angew. Chem. Int. Ed. 2005, 43, 1744 – 1752
Angewandte
Chemie
Axial ligation of the heme moiety by a
proximal imidazole group is observed in a
novel cytochrome c oxidase (CcO) activesite model 1 in which the copper ion is
bound to a N-(2-hydroxyphenyl)imidazole
moiety. Spectroscopic observations of 1
suggest the unique transformation of an
initial heme–m-peroxo–CuII species into a
heme–superoxide/CuI intermediate in the
course of the CcO oxygenation reaction at
low temperature.
Bicyclic b lactams are obtained by the twostep procedure shown in the scheme.
Alternatively, with the help of organoindium reagents, allenyl and propargyl
groups are introduced at the C4-position
of 2-azetidinones. R1 = H, 1R-(tert-butyldimethylsilyloxy)ethyl (TBSO(CH3)CH);
R2 = H, methyl, ethyl, n-butyl, phenyl,
THPOCH2, trimethylsilyl, 2-naphthyl;
R3 = H, methyl, phenyl; R4 = H, methyl.
Global currents: Quantum chemical
methodology has been used to investigate
the magnetically induced currents of both
neutral Buckminsterfullerene and its
spherically aromatic + 10 ion and has
allowed quantitative measurement of the
current strengths. Global sphere currents
(see picture), instead of local ring currents, are found to be the defining feature
of fullerene aromaticity.
J.-G. Liu, Y. Naruta,* F. Tani 1836 – 1840
A Functional Model of the Cytochrome c
Oxidase Active Site: Unique Conversion of
a Heme–m-peroxo–CuII Intermediate into
Heme–superoxo/CuI
Synthetic Methods
P. H. Lee,* Heechul Kim, K. Lee, M. Kim,
K. Noh, Hyunseok Kim,
D. Seomoon
1840 – 1843
The Indium-Mediated Selective
Introduction of Allenyl and Propargyl
Groups at the C4-Position of
2-Azetidinones and the AuCl3-Catalyzed
Cyclization of 4-Allenyl-2-azetidinones
Density Functional Calculations
M. P. Johansson, J. Juslius,
D. Sundholm*
1843 – 1846
Sphere Currents of Buckminsterfullerene
Fullerenes
Quantum chemical calculations and NMR
spectroscopic data suggest that the two
isomers of Y@C82(CF3)5 prepared by
trifluoromethylation of the endohedral
metallofullerene (EMF) contain chains of
four 1,4-C6(CF3)2 edge-sharing hexagons
(see picture). In striking contrast to the
empty fullerenes, which form complex
mixtures with up to 22 CF3 groups, EMF
Y@C82 only forms products with one,
three, and five CF3 groups.
Angew. Chem. Int. Ed. 2005, 43, 1744 – 1752
Active-Site Modeling
I. E. Kareev,* S. F. Lebedkin,
V. P. Bubnov, E. B. Yagubskii, I. N. Ioffe,
P. A. Khavrel, I. V. Kuvychko, S. H. Strauss,
O. V. Boltalina*
1846 – 1849
Trifluoromethylated Endohedral
Metallofullerenes: Synthesis and
Characterization of Y@C82(CF3)5
www.angewandte.org
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
1749
Contents
Inorganic Ring Systems
C. Redshaw,* M. R. J. Elsegood,
K. E. Holmes
1850 – 1853
Synthesis of Hexa- and Dodecanuclear
Organoaluminum Ring Structures
Incorporating the “Magic” Ph2C(X) Group
(X = O, NH)
Antibiotics
S. Hirano, S. Ichikawa,
A. Matsuda*
1854 – 1856
Total Synthesis of Caprazol, a Core
Structure of the Caprazamycin
Antituberculosis Antibiotics
Expanded Porphyrins
Y. Inokuma, T. Matsunari, N. Ono,*
H. Uno,* A. Osuka*
1856 – 1860
A Doubly N-Fused Benzohexaphyrin and
Its Rearrangement to a Fluorescent
Macrocycle upon DDQ Oxidation
The magic touch! By using the “magic”
group Ph2C(X) (X = O, NH), aluminum
ring systems such as 1 have been synthesized from trimethylaluminum. For
diphenylglycine (X = NH), both six- and
twelve-membered rings have been structurally identified.
TB and anti-TB: Two key steps in the
synthesis of caprazol (1), a core structure
of the antituberculosis antibiotics, are the
introduction of an aminoribose moiety by
b-selective ribosylation without the use of
neighboring-group participation and the
construction of the diazepanone moiety.
A retro-Diels–Alder reaction of a
b-bicyclo[2.2.2]octadiene-fused precursor
yields the doubly N-fused b-benzo[28]hexaphyrin(1.1.1.1.1.1) shown, which
undergoes oxidative rearrangement upon
treatment with 2,3-dichloro-5,6-dicyano1,4-benzoquinone (DDQ) to yield a macrocycle that emits fluorescence in the
visible/near-IR region.
Bang on target: The highly explosive
Group 6 azides Mo(N3)6 and W(N3)6 are
prepared by the reaction of Me3SiN3 with
MoF6 and WF6, respectively. The structure
of W(N3)6 has perfect rhombohedral
C3 symmetry (see picture). The reaction of
Mo(N3)6 and W(N3)6 with ionic azides
leads to the formation of [Mo(N3)7] and
[W(N3)7] , respectively, the first binary
heptaazides. Controlled decomposition of
these anions produces [NMo(N3)4] and
[NW(N3)4] .
Azides
R. Haiges,* J. A. Boatz, R. Bau,
S. Schneider, T. Schroer, M. Yousufuddin,
K. O. Christe*
1860 – 1865
Polyazide Chemistry: The First Binary
Group 6 Azides, Mo(N3)6, W(N3)6,
[Mo(N3)7] , and [W(N3)7] , and the
[NW(N3)4] and [NMo(N3)4] Ions
1750
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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Angew. Chem. Int. Ed. 2005, 43, 1744 – 1752
Angewandte
Chemie
Asymmetric Catalysis
A. Moyano,* M. Rosol, R. M. Moreno,
C. Lpez, M. A. Maestro
1865 – 1869
Formation of a carbon–palladium bond to
the unsubstituted cyclopentadiene ring
occurs during the cyclopalladation of 4ferrocenyl-1,3-oxazolines and leads to a
new type of metalated ferrocene (see
scheme). These chiral complexes catalyze
the asymmetric aza-Claisen rearrangement of allylic imidates.
Oxazoline-Mediated Interannular
Cyclopalladation of Ferrocene: Chiral
Palladium(ii) Catalysts for the
Enantioselective Aza-Claisen
Rearrangement
CC Coupling
D. S. Surry, X. Su, D. J. Fox,
V. Franckevicius, S. J. F. Macdonald,
D. R. Spring*
1870 – 1873
A biaryl banquet! Biphenyls with four ortho
substituents, heteroaromatic compounds, iodinated biaryls, and medium
rings containing biaryls are all readily
synthesized by organocuprate oxidation.
The utility of this new methodology is
illustrated by the efficient synthesis of the
medium-ring core of sanguiin H-5 (see
scheme).
Synthesis of Medium-Ring and Iodinated
Biaryl Compounds by Organocuprate
Oxidation
Palladium Migration
J. Zhao, M. Campo,
R. C. Larock*
“Through-space” migration of palladium
between remote carbon atoms appears to
take place in the generation of p-allyl–
palladium complexes, which are useful
intermediates in organic synthesis. The
reaction of halogenated arenes with
alkynes under Pd-migration conditions
provides the mixture of allylic esters A–C
(see reaction shown; X = Br, I; R1 = H,
OMe, CO2Et, Cl; R2 = Ph, tBu).
Complementarity between different techniques (magnetization, HF-HFEPR,
FDMRS) and angular-overlap-model calculations allow the precise determination
of the spin-Hamiltonian parameters in an
isolated octahedral NiII complex (see
structure), which exhibits the largest easy
axis magnetic anisotropy reported to date
(D = 10.1 cm1, E/ j D j = 0.02).
Angew. Chem. Int. Ed. 2005, 43, 1744 – 1752
www.angewandte.org
1873 – 1875
Consecutive Vinylic to Aryl to Allylic
Palladium Migration and Multiple CH
Activation Processes
Magnetic Properties
G. Rogez,* J.-N. Rebilly, A.-L. Barra,
L. Sorace, G. Blondin, N. Kirchner,
M. Duran, J. van Slageren, S. Parsons,
L. Ricard, A. Marvilliers,
T. Mallah*
1876 – 1879
Very Large Ising-Type Magnetic
Anisotropy in a Mononuclear NiII Complex
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
1751
Contents
Pummerer-like Reactions
B. Laleu, P. Mobian, C. Herse,
B. W. Laursen, G. Hopfgartner,
G. Bernardinelli, J. Lacour* 1879 – 1883
Resolution of [4]Heterohelicenium Dyes
with Unprecedented Pummerer-like
Chemistry
CS Bond Formation
S. Poturovic, M. S. Mashuta,
C. A. Grapperhaus*
1883 – 1887
Carbon–Sulfur Bond Formation between a
Ruthenium-Coordinated Thiyl Radical and
Methyl Ketones
Addition of an enantiopure sulfoxide
auxiliary is the key to the resolution of
highly stable [4]helicenium dyes. This
transformation allows a facile chromatographic separation of the diastereomers
(the structure of one such diastereomer is
shown; S yellow, O red, N blue). Then an
unprecedented Pummerer-like CC bond
fragmentation takes place to release the
enantiopure cations.
A metal-coordinated thiyl radical was
revealed by the electrochemical oxidation
of a ruthenium(iii)–thiolate in acetone
(and related ketones). The subsequent
reaction between the radical intermediate
and acetone resulted in CS bond formation and ultimately a ruthenium(iii)–
thioether product (see picture). A
mechanism that involves reaction of the
enol tautomer of acetone with the radical
is proposed.
Service
Keywords
1888
Authors
1889
Angewandte’s
Sister Journals
Preview
1752
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
1890 – 1891
1893
Angew. Chem. Int. Ed. 2005, 43, 1744 – 1752
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