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Graphical Abstract Angew. Chem. Int. Ed. 262004

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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. Wang, A. Fichera, K. Kumar, D. A. Tirrell*:
Alternative Translations of a Single RNA Message: An Identity
Switch of (2S,3R)-4,4,4-Trifluorovaline between Valine and Isoleucine Codons
DOI: 10.1002/anie.200454036
Published online: June 21, 2004
Z. Deng, C. Mao*:
Molecular Lithography with DNA Nanostructures
DOI: 10.1002/anie.200460257
Published online: June 17, 2004
A. Pfitzner,* M. F. Br#u, J. Zweck, G. Brunklaus, H. Eckert*:
Phosphorus Nanorods—Two Allotropic Modifications of a LongKnown Element
DOI: 10.1002/anie.200460244
Published online: June 17, 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.
Obituary
S. Chandrasekhar (1930–2004): Discotic Liquid Crystals
3360
P E. Cladis, B. R. Ratna and R. Shashidar
Books
Photochromism
3362
Heinz D$rr, Henri Bouas-Laurent
reviewed by K. Uchida
Affinity, that Elusive Dream
3362
Mi Gyung Kim
reviewed by S. Tomic, P. M. Vauthelin
Highlights
Ligand Design
F. Glorius*
3364 – 3366
Chiral Olefin Ligands—New “Spectators”
in Asymmetric Catalysis
3350
Bidentate chiral olefin ligands such as 1
(shown with its catalytically active Rh
complex 2) have been applied successfully
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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in asymmetric catalysis recently. New
coordination geometries are possible with
this class of ligands, and the electronic
character of the olefin ligand can be varied
over a wide range, leading to catalysts
with increased stability, selectivity, and
catalytic activity.
Angew. Chem. Int. Ed. 2004, 43, 3350 – 3356
Angewandte
Chemie
Reviews
Addition to C–C Multiple Bonds
It was the 19th century when Markovnikov
set out his rules for the regioselectivity of
addition reactions to C C multiple bonds.
Despite the traditional view, it is often
possible nowadays to direct the regioselectivity of such reactions towards the
Markovnikov or anti-Markovnikov products by using transition-metal catalysts
(see picture). In this Review, recent progress in the selective functionalization of
alkenes and alkynes is described.
A long-term goal of synthetic and catalytic
chemistry for several decades has been
the selective oxidation of organic chemicals with molecular oxygen. This goal is
rapidly becoming a reality with the development of new “palladium oxidase” reactions. New catalysts exhibit improved
stability and activity and they utilize
oxidatively stable ligands that modulate
reaction selectivity.
M. Beller, J. Seayad, A. Tillack,
H. Jiao
3368 – 3398
Catalytic Markovnikov and anti-Markovnikov Functionalization of Alkenes and
Alkynes: Recent Developments and
Trends
Catalytic Oxidations
S. S. Stahl*
3400 – 3420
Palladium Oxidase Catalysis: Selective
Oxidation of Organic Chemicals by Direct
Dioxygen-Coupled Turnover
Communications
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Angew. Chem. Int. Ed. 2004, 43, 3350 – 3356
Left-handed-helical nanoropes are formed
from higher-order self-assemblies of chiral
aggregates during the gelation of a rigid
p-conjugated oligo(p-phenylenevinylene)
with remote chiral handles (see picture;
R = C12H25). The concentration- and temperature-dependent CD-signal changes
observed for these assemblies are indicative of a helix transition. This process is
reminiscent of the folding and unfolding
of helical biological macromolecules.
Helical Nanostructures
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S. J. George, A. Ajayaghosh,* P. Jonkheijm,
A. P. H. J. Schenning,
E. W. Meijer
3422 – 3425
Coiled-Coil Gel Nanostructures of
Oligo(p-phenylenevinylene)s: GelationInduced Helix Transition in a HigherOrder Supramolecular Self-Assembly of a
Rigid p-Conjugated System
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
3351
Contents
Enzymatic Mechanisms
S. Karthikeyan, Z. Zhao, C.-l. Kao, Q. Zhou,
Z. Tao, H. Zhang,*
H.-w. Liu*
3425 – 3429
Structural Analysis of 1-Aminocyclopropane-1-Carboxylate Deaminase:
Observation of an Aminyl Intermediate
and Identification of Tyr 294 as the
Active-Site Nucleophile
Finding an angle of attack: Structural
studies of 1-aminocyclopropane-1-carboxylate (ACC) deaminase complexed
with the tight-binding inhibitor 1-aminocyclopropanephosphonate (ACP, see picture) revealed the existence of an aminyl
adduct intermediate. The crystal structure
of the enzyme and mutation studies
suggest that the ring cleavage of ACC is
initiated by nucleophilic attack by Tyr 294.
Liquid Crystals
A “peelable banana” is formed when a
bent-core molecule is linked to a rodlike
mesogen through a flexible aliphatic
spacer. This is an appropriate description
of this novel low-molar-mass organic
system, which displays a transition from a
biaxial nematic (Nb) phase to a biaxial
smectic A phase. The illustration gives a
schematic representation of the dimeric
molecules in the Nb phase as well as the
corresponding textural and conoscopic
patterns obtained.
C. V. Yelamaggad, S. Krishna Prasad,*
G. G. Nair, I. S. Shashikala,
D. S. Shankar Rao, C. V. Lobo,
S. Chandrasekhar
3429 – 3432
A Low-Molar-Mass, Monodispersive,
Bent-Rod Dimer Exhibiting Biaxial
Nematic and Smectic A Phases
Fluorescent Amino Acids
M.-P. Brun, L. Bischoff,
C. Garbay*
No bulkier than a tryptophan or a tyrosine
residue are the fluorescent coumaryl
amino acids described. These building
blocks can be synthesized rapidly with
high enantiomeric purity and introduced
readily into a peptidic sequence. Their
fluorescence properties allow, for example, the investigation of the cellular localization of labeled peptides through confocal fluorescence microscopy (see picture).
3432 – 3436
A Very Short Route to Enantiomerically
Pure Coumarin-Bearing Fluorescent
Amino Acids
Magnetism in Clusters
K. Hegetschweiler,* B. Morgenstern,
J. Zubieta,* P. J. Hagrman, N. Lima,
R. Sessoli,* F. Totti
3436 – 3439
Strong Ferromagnetic Interactions in
[V8O14(H 2taci)2]: An Unprecedented
Large Spin Ground State for a Vanadyl
Cluster
3352
Tactics with taci: Strong ferromagnetic
interactions (up to 150 cm 1) and an
S = 3 ground state have been observed in
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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the octanuclear vanadyl cluster
[V8O14(H 2taci)2] (taci = 1,3,5-triamino1,3,5-trideoxy-cis-inositol; see structure:
V yellow, O red, N blue, C black) where the
polydentate taci ligand forces some of the
coordination polyhedra into a mutually
orthogonal arrangement. Ab initio DFT
calculations confirm the magnetostructural analysis.
Angew. Chem. Int. Ed. 2004, 43, 3350 – 3356
Angewandte
Chemie
Molecule with three faces: Two of the
three possible configurations that a stable
silicate with five carbon substituents can
adopt have been observed by NMR
spectroscopy and shown to be in dynamic
equilibrium through a Berry pseudorotation. The thermodynamics and kinetics of
their exchange are in good agreement with
calculations. The major configuration
(from the crystal structure of the nBu4N+
salt) is shown in the center of the picture.
Pentaorganosilicate Pseudorotamers
A whiter shade of PAl: The reaction of LAlI
with white phosphorus yields the first
main-group complex [(LAl)2P4]
(L = HC(CMeNAr)2, Ar = 2,6-iPr2C6H3)
containing the {P4}4 moiety, in which two
P–P edges of the P4 tetrahedron are
opened and each is bridged by a LAl
moiety (see structure). The results are
supported by quantum chemical calculations.
Phosphorous Compounds
E. P. A. Couzijn, M. Schakel,
F. J. J. de Kanter, A. W. Ehlers, M. Lutz,
A. L. Spek,
K. Lammertsma*
3440 – 3442
Dynamic Configurational Isomerism of a
Stable Pentaorganosilicate
Y. Peng, H. Fan, H. Zhu, H. W. Roesky,*
J. Magull, C. E. Hughes
3443 – 3445
[{HC(CMeNAr)2}2Al2P4] (Ar = 2,6iPr2C6H3): A Reduction to a Formal {P4}4
Charged Species
Radical Reactions
R. S. Grainger,*
P. Innocenti
Oxygen or nitrogen? Radical chemists
overwhelmingly choose to work with xanthates rather than dithiocarbamates, yet
the latter offer a distinct advantage in the
case of a new method for generating
carbamoyl radicals. Functionalized lac-
tams of various ring sizes can be prepared
in an operationally simple procedure
involving irradiation or heating in the
presence of a radical initiator (see
scheme).
3445 – 3448
Dithiocarbamate Group Transfer
Cyclization Reactions of Carbamoyl
Radicals under “Tin-Free” Conditions
C C Coupling Reactions
E. Shirakawa,* Y. Yamamoto, Y. Nakao,
S. Oda, T. Tsuchimoto,
T. Hiyama*
3448 – 3451
Alkynes and 1,2-dienes insert into the
carbon–tin bond of alkynylstannanes to
afford various stannyldienynes in the
presence of a nickel catalyst (see scheme).
Angew. Chem. Int. Ed. 2004, 43, 3350 – 3356
This is the first example of a transitionmetal-catalyzed tandem carbometalation
of two different carbon–carbon unsaturated bonds.
www.angewandte.org
Nickel-Catalyzed Tandem Carbostannylation of Alkynes and 1,2-Dienes with
Alkynylstannanes
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
3353
Contents
Nanostructures
G. Hu, D. Ma,* L. Liu, M. Cheng,
X. Bao*
3452 – 3456
In Situ Assembly of Zeolitic Building
Blocks into High-Order Structures
Zeolitic hierarchical structures with complex morphologies, such as the peonyshaped superstructure illustrated in the
picture, are synthesized in a one-pot dualtemplate assembly reaction. One template acts as the structural directing agent
to construct the microporous building
block (zeolite), and a second template is
employed to assemble these building
blocks into a superlattice.
Noble-Gas Compounds
M. Tramšek,* P. Benkič,
B. Žemva*
Wrapped in a cloak of noble-gas fluoride:
Coordination compounds with XeF2 as a
ligand on the metal center are more
abundant than considered in the past. The
structure of the coordination compound
Ca2(XeF2)9(AsF6)4 is reported. For the first
time one calcium center is found to be
coordinated only with XeF2 molecules
(a homoleptic center), while the other
calcium center is coordinated with XeF2
and [AsF6] as ligands (see structure; As
yellow, Ca gray, F green, Xe magenta).
3456 – 3458
The First Compound Containing a Metal
Center in a Homoleptic Environment of
XeF2 Molecules
Cyclizations
J. H. Koh, M. R. GagnS*
3459 – 3461
PdII- and PtII-Mediated Polycyclization
Reactions of 1,5- and 1,6-Dienes: Evidence
in Support of Carbocation Intermediates
Pincer-ligated PdII and PtII dicationic
complexes efficiently generate cations
from 1,5- and 1,6-dienes. These transient
cations can be selectively trapped with
heteroatoms, alkenes, and through pina-
Enantioselective Sensors
J. Zhao, T. M. Fyles,
T. D. James*
3461 – 3464
Chiral Binol–Bisboronic Acid as
Fluorescence Sensor for Sugar Acids
3354
col rearrangements. For example, trienylphenol 1 is converted into tetracyclic 2 in
high yield and diastereomeric ratio (see
scheme).
A novel fluorescence response to enantiomeric analytes was observed for binol–
bisboronic acid sensors (R- or S-1): One
enantiomer of the analyte enhances and
the other enantiomer diminishes the
fluorescence of 1. So, the fluorescence
intensity of R-1 was enhanced by d-tartaric
acid and diminished by l-tartaric acid (see
scheme). These changes are mirrored by
the S sensor.
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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Angew. Chem. Int. Ed. 2004, 43, 3350 – 3356
Angewandte
Chemie
Activation of one C C and three C H
bonds associated with a methyl group
attached to an organic fragment has been
achieved. Two compounds, which arise
from the activation of two (1) and three
C H bonds of a methyl group of 6,6’dimethyl-2,2’-bipyridine (Me2bipy), and
pentanuclear cluster 2, which contains a
carbide ligand arising from a methyl
group of Me2bipy, were isolated from
reactions of [Ru3(CO)12] with Me2bipy.
* = CO.
C H/C C Activation
J. A. Cabeza,* I. da Silva, I. del RTo,
L. MartTnez-MSndez, D. Miguel,
V. Riera
3464 – 3467
Activation of All Bonds of a Methyl Group
Attached to an Organic Fragment
Natural Products Synthesis
S. Barluenga, P. Lopez, E. Moulin,
N. Winssinger*
3467 – 3470
Back to its origins: Pochonin C was synthesized in 11 steps from the four fragments shown in the scheme. This asymmetric synthesis and the conversion of
Modular Asymmetric Synthesis of
Pochonin C
pochonin C into radicicol defines the
configuration at the center bearing the
chlorine atom as S. Ipc = isopenocampheyl, PG = protecting group.
Bidentate P,N Ligands
P. N. M. Botman, O. David, A. Amore
J. Dinkelaar, M. T. Vlaar, K. Goubitz,
J. Fraanje, H. Schenk, H. Hiemstra,*
J. H. van Maarseveen*
3471 – 3473
An intramolecular SNAr reaction makes
the synthesis of enantiopure MAP(O)-type
P,N ligands in high yields possible (see
scheme) and demonstrates that the syn-
thetic potential of the 85-year-old Staudinger reaction between phosphanes and
azides is still far from being exhausted.
Nf = nonafluorobutanesulfonate.
Phosphorus Heterocycles
Thermally stable silylene Si{1,2(NCH2tBu)2C6H4} reacts with 1H-phosphirenes to give the first isolated 2,3dihydro-1,3-phosphasiletes, a unique type
of zwitterion, and 1,2-dihydro-1,2-phosphasiletes. The novel 2-phospha-4-silabicyclo[1.1.0]butane (see picture) is a reactive intermediate in the reaction, whose
course can be tuned by changing the
substituents.
Angew. Chem. Int. Ed. 2004, 43, 3350 – 3356
A Staudinger Approach towards BinolDerived MAP-Type Bidentate P,N Ligands
J. C. Slootweg, F. J. J. de Kanter,
M. Schakel, A. W. Ehlers, B. Gehrhus,
M. Lutz, A. M. Mills, A. L. Spek,
K. Lammertsma*
3474 – 3477
2-Phospha-4-silabicyclo[1.1.0]butane as a
Reactive Intermediate
www.angewandte.org
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
3355
Contents
Protein Structures
Y.-S. Jung, M. Sharma,
M. Zweckstetter*
3479 – 3481
Simultaneous Assignment and Structure
Determination of Protein Backbones by
Using NMR Dipolar Couplings
Running on automatic: Folds for proteins
up to around 125 residues can be achieved rapidly and without manual inter-
Scanning Probe Techniques
Stranded on the surface: The modulation
of the amperometric feedback current in
scanning electrochemical microscopy
(SECM) through coulomb interactions
between the phosphate groups of immobilized oligonucleotides and a freely diffusing, negatively charged redox mediator
is used for imaging DNA spots (see
picture) and establishing a simple and
efficient label-free electrochemical detection of complementary hybridization on
DNA microarrays.
F. Turcu, A. Schulte, G. Hartwich,
W. Schuhmann*
3482 – 3485
Label-Free Electrochemical Recognition of
DNA Hybridization by Means of Modulation of the Feedback Current in SECM
Polyoxometalates
F. Hussain, B. S. Bassil, L.-H. Bi,
M. Reicke, U. Kortz*
3485 – 3488
Structural Control on the Nanomolecular
Scale: Self-Assembly of the Polyoxotungstate Wheel [{b-Ti2SiW10O39}4]24
vention by integration of bioinformatics
tools with NMR spectroscopy in dilute
liquid-crystalline phases (see picture).
Data intensive and time-consuming
assignment of backbone resonances prior
to structure determination is not required
any more. This greatly accelerates
structure determination of proteins by
NMR spectroscopy.
Wheel meet again: The titanium(iv) substituted [{b-Ti2SiW10O39}4]24 (1) consists
of four b-Keggin moieties that are linked
via Ti-O-Ti bonds leading to a cyclic
arrangement (see picture; red WO6,
green TiO6, and blue SiO4). The wheels
stack to give a tunnel-like structure. Synthesis of 1 is from the dilacunary precursor [g-SiW10O36]8 and gives insights into
the mechanism of formation of polyoxoanion assemblies.
Communications labeled with this symbol have been judged by two referees as being “very important papers”.
Service
Keywords
3492
Authors
3493
Angewandte’s
Sister Journals
Preview
3356
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
3490 – 3491
3495
Angew. Chem. Int. Ed. 2004, 43, 3350 – 3356
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