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Graphical Abstract Angew. Chem. Int. Ed. 142005

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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:
J. Malo, J. C. Mitchell, C. Vnien-Bryan, J. R. Harris, H. Wille,
D. J. Sherratt, A. J. Turberfield*
Engineering a 2D Protein–DNA Crystal
V. Huber, M. Katterle, M. Lysetska, F. Wrthner*
Reversible Self-Organization of Semi-Synthetic Zinc Chlorins into
Well-Defined Rod Antennae
F. Lpez, S. R. Harutyunyan, A. Meetsma, A. J. Minnaard,
B. L. Feringa*
Copper-Catalyzed Enantioselective Conjugate Addition of
Grignard Reagents to a,b-Unsaturated Esters
N. P. Grimster, Carolyn Gauntlett, C. R. A. Godfrey,
M. J. Gaunt*
Intermolecular Palladium-Catalyzed Alkenylation of Indoles
through Solvent-Controlled Regioselective C–H
Functionalization
A. Tavassoli, S. J. Benkovic*
Genetically Selected Cyclic Peptide Inhibitors of AICAR
Transformylase Homodimerization
R. Banerjee, P. M. Bhatt, M. T. Kirchner, G. R. Desiraju*
Structural Studies of the System Sodium Saccharinate Hydrate:
A Model for Crystallization
News
Mitsui Chemicals Catalysis Science Awards: E. Jacobsen, S. Kobayashi, R. Kuwano, K. Itami
2052
Books
Modern Aldol Reactions
Rainer Mahrwald
reviewed by M. Breuning
2053
Amines
Stephen A. Lawrence.
reviewed by M. North
2053
Highlights
Missing link! The boryl-bridged complex
[Cp*Fe(CO)2BCl2Pd(PCy3)] (1), which was
recently reported by Braunschweig et al. in
this journal, fills one of the remaining
holes in the edifice of B1 Mm chemistry.
The {Pd(Cy3)} fragment in 1 acts as both a
Lewis acid and a Lewis base to coordinate
the Fe and B centers, respectively.
Boryl Complexes
T. P. Fehlner*
2056 – 2058
Borane Mimics of C1 Mm Organometallic
Complexes
Correspondence
Artemisinin Derivatives
Discussion is reopened regarding C10substituted derivatives of the peroxidebased antimalarial agent artemisinin (see
picture); they are shown to react readily
with iron(ii)-heme to provide heme–drug
adducts in high yields. Substitution or
steric hindrance at C10 does not affect the
reactivity of the peroxide bond and, thus,
does not alter the ability of these powerful
antimalarial drugs to alkylate heme.
S. A.-L. Laurent, A. Robert,*
B. Meunier*
2060 – 2063
C10-Modified Artemisinin Derivatives:
Efficient Heme-Alkylating Agents
2042
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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Angew. Chem. Int. Ed. 2005, 44, 2042 – 2050
Angewandte
Chemie
In light of the discussion on C10-substituted derivatives of the antimalarial agent
artemisinin in the preceding correspondence article which relates to his earlier
work, R. K. Haynes reiterates here that
there is no correlation between the ability
of artemisinins to react with heme- or
non-heme-FeII and their antimalarial
activity.
Artemisinin Derivatives
R. K. Haynes*
2064 – 2065
Reply to Comments on
“Highly Antimalaria-Active Artemisinin
Derivatives: Biological Activity Does Not
Correlate with Chemical Reactivity”
Reviews
Host—Guest Chemistry
Snapshots of interacting species are possible with molecules that are reversibly
encapsuled together and temporarily
isolated from bulk solution. The systems
give physical organic chemistry a tool that
reveals intermolecular interactions not
observable by other methods.
Simultaneously encapsulated molecules
show new forms of stereoisomerism,
asymmetric interactions, and amplified
reactivity. The picture shows a single
molecule of benzene solvent in contact
with each end of p-ethyltoluene.
J. Rebek, Jr.*
2068 – 2078
Simultaneous Encapsulation: Molecules
Held at Close Range
Communications
Electrocatalysis
Stretching exercises: The electrochemical
behavior of pseudomorphic palladium
monolayers (PdML) on various singlecrystal electrodes is investigated (see
picture) to demonstrate the influence of
lateral compression and dilation on surface activity. The adsorption behavior and
the catalytic activity for formic acid
electrooxidation varies dramatically
depending on whether the palladium
monolayer is compressed or dilated by the
single-crystal electrode.
For the USA and Canada:
ANGEWANDTE CHEMIE International
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Meacham Ave., Elmont, NY 11003. Periodicals
Angew. Chem. Int. Ed. 2005, 44, 2042 – 2050
L. A. Kibler,* A. M. El-Aziz, R. Hoyer,
D. M. Kolb
2080 – 2084
Tuning Reaction Rates by Lateral Strain in
a Palladium Monolayer
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2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2043
Angewandte
Chemie
Partially filling a colloidal crystal can give
rise to mesoscopic rings (see scheme).
The liquid forms rings by capillary forces
in the wedges around the contact points
between particles. The liquid is solidified,
the templating particles are removed, and
dispersions of solid rings remain.
Lead around: The cyclic [Pb5]4 ion can be
stabilized as an organometallic complex
with the {Mo(CO)3} fragment. This com-
F. Yan,* W. A. Goedel*
2084 – 2088
The Preparation of Mesoscopic Rings in
Colloidal Crystal Templates
The three-dimensional fold of an immobilized polypeptide is predicted at atomic
resolution from solid-state NMR spectroscopic data (see picture) obtained for a
single uniformly [13C,15N] isotope labeled
sample. The method involves the combined analysis of conformation-dependent NMR frequencies and short 1H–1H
distances and may lead to the rapid
characterization of three-dimensional
protein structures.
Solid-State NMR Spectroscopy
plex is formed by the reaction of [Pb9]4
with [MesMo(CO)3] (Mes = 1,3,5-trimethylbenzene). In the solid state this highly
charged anion forms a linear chain with
strong interactions between the potassium cations and the carbonyl oxygen
atoms (see picture; cyan Mo, purple K,
and red Pb; C and O atoms are omitted).
Zintl Anions
A. Lange, S. Becker,* K. Seidel, K. Giller,
O. Pongs, M. Baldus*
2089 – 2092
A Concept for Rapid Protein-Structure
Determination by Solid-State NMR
Spectroscopy
L. Yong, S. D. Hoffmann, T. F. Fssler,*
S. Riedel, M. Kaupp*
2092 – 2096
[Pb5{Mo(CO)3}2]4 : A Complex Containing
a Planar Pb5 Unit
Carbohydrate Mimetics
It takes two: Sugar diamino acids which
differ from established sugar amino acids
by an additional amino group provide
access to novel branched oligosaccharide
mimetics and a novel class of aminoglycoside mimetics such as 1. The latter are
of great significance as potential ligands
for new RNA targets emerging in the postgenome era.
Angew. Chem. Int. Ed. 2005, 44, 2042 – 2050
Mesoscopic Rings
F. Sicherl, V. Wittmann*
2096 – 2099
Orthogonally Protected Sugar Diamino
Acids as Building Blocks for Linear and
Branched Oligosaccharide Mimetics
www.angewandte.org
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2045
Contents
Nanoporous Materials
J. M. Mack, H. Tsuchiya,
P. Schmuki*
2100 – 2102
High-Aspect-Ratio TiO2 Nanotubes by
Anodization of Titanium
Growing holes: With the aid of a new
technique highly organized surface layers
of TiO2 nanotubes that are open at one
end (see picture) are formed by the
anodization of titanium. The pore structure is determined by the pH gradient
within the forming pore, this in turn is
controlled by the electrochemical sweep
rate and the electrolyte concentration.
Copper Complexes
S. Ye, B. Sarkar, F. Lissner, T. Schleid,
J. van Slageren, J. Fiedler,
W. Kaim*
2103 – 2106
Three-Spin System with a Twist: A
Bis(semiquinonato)copper Complex with
a Nonplanar Configuration at the
Copper(ii) Center
Mesoporous Materials
K. Landskron, G. A. Ozin*
2107 – 2109
Periodic Mesoporous Organosilicas:
Self-Assembly from Bridged Cyclic
Silsesquioxane Precursors
A new twist: Structural twisting by about
328 between the semiquinoneiminecopper(ii) entities in 2 caused by weak Cu–S
interaction results in a different spin
arrangement (›,fl,›) than for planar 1
(›,›,fl). Most revealingly, 2 has an EPR
spectrum typical for a radical whereas 1
displays a signal for a CuII center. Oxidation state distributions for the 22+,+,0, ,2
forms are assigned on the basis of UV/
Vis/NIR spectroelectrochemistry.
No holes barred: Trimethylene-bridged 1
can be prepared from [{SiCH2(OEt)2}3].
Compound 1 can be directed to selfassemble by a tri-block copolymer template to form a periodic mesoporous
organosilica with highly ordered and uniform-diameter mesopores in which practically all the building blocks remain intact
within the as-synthesized and templateextracted material.
Enzyme Engineering
T. Woodhall, G. Williams, A. Berry,
A. Nelson*
2109 – 2112
Creation of a Tailored Aldolase for the
Parallel Synthesis of Sialic Acid Mimetics
2046
Broadening substrate specificity: A modified form of sialic acid aldolase (E192N)
exhibits a 640-fold switch in substrate
specificity relative to the wild-type
enzyme. Ozonolysis of the unsaturated
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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amides 1, followed by an E192N-mediated
step, was exploited in the parallel synthesis of 14 different sialic acid mimetics of
general structure 2.
Angew. Chem. Int. Ed. 2005, 44, 2042 – 2050
Angewandte
Chemie
Specific, asymmetric, and mild: Oxazoline
(Oxa), a removable chelating chiral auxiliary, assists in the asymmetric activation
of C(sp3) H bonds at the b position and
C(sp2) H bonds at the g position. Pd(OAc)2 is an effective catalyst for the
selective and asymmetric iodination of
methyl, cyclopropyl, and aryl groups at
room temperature (see formulae).
Asymmetric Catalysis
R. Giri, X. Chen, J.-Q. Yu*
2112 – 2115
Palladium-Catalyzed Asymmetric
Iodination of Unactivated C H Bonds
under Mild Conditions
Crystal Engineering
R. Natarajan, G. Savitha, P. Dominiak,
K. Wozniak, J. N. Moorthy* 2115 – 2119
Corundum, Diamond, and PtS
Metal–Organic Frameworks with a
Difference: Self-Assembly of a Unique
Pair of 3-Connecting D2d-Symmetric
3,3’,5,5’-Tetrakis(4-pyridyl)bimesityl
A ligand with a twist: The coordination of
distorted-tetrahedral D2d-symmetric tetrapyridylbimesityl (tpb) with Oh, Td, and D4h
metal centers leads to metal–organic
frameworks with unprecedented topologies related to those of corundum, diamond, and PtS, respectively (see picture).
Graphitic carbon nanotubes that comprise graphene layers aligned perpendicular to the tube axis (see image; arrow
indicates tube axis) were obtained by
stepwise carbonization of preorganized
disclike molecules in a porous alumina
template. The alignment, size, wall thickness, and shape of the tubes were all
controlled by this method.
Open the gate: Thermoresponsive gating
membranes based on interpenetrating
polymer networks composed of polyacrylamide (PAAM) and poly(acrylic acid)
(PAAC) have inverse gating characteristics, with opening of the membrane pores
induced by a decrease rather than an
increase in temperature (see picture;
UCST = upper critical solution temperature). The membranes provide a new
mode of phase-transition behavior for
Angew. Chem. Int. Ed. 2005, 44, 2042 – 2050
Nanotube Synthesis
L. Zhi, J. Wu, J. Li, U. Kolb,
K. Mllen*
2120 – 2123
Carbonization of Disclike Molecules in
Porous Alumina Membranes: Toward
Carbon Nanotubes with Controlled
Graphene-Layer Orientation
Polymer Membranes
L.-Y. Chu,* Y. Li, J.-H. Zhu,
W.-M. Chen
2124 – 2127
Negatively Thermoresponsive
Membranes with Functional Gates Driven
by Zipper-Type Hydrogen-Bonding
Interactions
thermoresponsive “smart” membrane
actuators.
www.angewandte.org
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2047
Contents
Carboranes
L. Deng, H.-S. Chan, Z. Xie* 2128 – 2131
Synthesis, Reactivity, and Structural
Characterization of a 14-Vertex Carborane
The largest known carborane, which has
14 vertices, was prepared by the reaction
of arachno-carborane tetraanion 1 with
HBBr2·SMe2 (see scheme). The reactivity
of both 13- (2) and 14-vertex carboranes
Electrocatalysis
J. Zhang, M. B. Vukmirovic, Y. Xu,
M. Mavrikakis,*
R. R. Adzic*
2132 – 2135
Controlling the Catalytic Activity of
Platinum-Monolayer Electrocatalysts for
Oxygen Reduction with Different
Substrates
Nanostructures
P. C. Burns,* K.-A. Kubatko, G. Sigmon,
B. J. Fryer, J. E. Gagnon, M. R. Antonio,
L. Soderholm
2135 – 2139
Actinyl Peroxide Nanospheres
Nanotechnology
J. Zhan,* Y. Bando, J. Hu, Z. Liu, L. Yin,
D. Golberg
2140 – 2144
Fabrication of Metal–Semiconductor
Nanowire Heterojunctions
2048
(3 and 4) has also been examined. The key
to the successful preparation of supracarboranes is to block the redox reactions
between carborane anions and RBX2
reagents.
Peak performance: Electrochemical
experiments show that the oxygen reduction reaction (ORR) on platinum monolayers supported on various transition
metals exhibits a volcano-type behavior
(see graph). Calculations reveal that
bond-breaking occurs more easily as
bond-making becomes harder, and why
the Pd-supported Pt monolayer (PtML/Pd(111)) has higher ORR activity than pure
Pt(111).
Waste not: Actinyl nanospheres selfassembled from alkaline solutions have
been shown to be composed of 24, 28,
and 32 actinyl peroxide polyhedra (for
example, see picture of the uranyl peroxide polyhedra (U-28)). The nanospheres
represent a new class of polyoxometalates, and their formation in nuclear waste
may have an impact on the mobility of
actinides in the environment.
Nanoscale sensors and switches for
future electronics may take advantage of
metal–semiconductor end-to-end nanowire contacts that can be made by simultaneous evaporation of In and SiO powders. The In and Si subnanowires (indicated) are crystallographically oriented at
each junction and are sheathed by silica
nanotubes.
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
Angew. Chem. Int. Ed. 2005, 44, 2042 – 2050
Angewandte
Chemie
Fluorescence Biochemistry
G. F. Kaufmann, M. M. Meijler, C. Sun,
D.-W. Chen, D. P. Kujawa, J. M. Mee,
T. Z. Hoffman, P. Wirsching, R. A. Lerner,*
K. D. Janda*
2144 – 2148
Enzymatic Incorporation of an AntibodyActivated Blue Fluorophore into DNA
Antibodies as light switches: The deoxynucleotide analogue–stilbene conjugate 1
can be incorporated into nascent DNA by
DNA polymerase activity. The blue fluorescence of stilbene is detected only upon
binding of an antibody that specifically
Angew. Chem. Int. Ed. 2005, 44, 2042 – 2050
recognizes the stilbene-modified nucleotide. Therefore, DNA generated through
PCR with 1 in the substrate pool can be
used for hybridization assays in which
detection is triggered by the antibody (see
scheme).
The deck is stacked in favor of future
photonic devices. Novel photochromic
crystals comprise alternating layers of two
conformations of diarylethene 1 a. Irradiation with UV light induces isomerization of only one conformer to the bluecolored, closed-ring form, 1 b. This selective reactivity is ascribed to the difference
in distance between the reactive carbon
atoms of the two conformers.
Photochemistry
Aqua and nitrate forms of a CoII center are
reversibly interconverted within a squaregrid complex because of flexible side
chains attached to a rodlike ligand (see
scheme; Co yellow, N blue, O red). The
ligand exchange proceeds in a singlecrystal-to-single-crystal fashion despite
the drastic structural changes at the metal
center. All processes are observed by in
situ X-ray crystallography.
Coordination Networks
One lump or two! Selective etching of
twinned seeds, mediated by HCl and the
oxygen in air, resulted in high yields of
perfect single-crystal silver nanocubes in a
range of sizes (30–130 nm). The chloride
ion enhances oxidation and prevents
aggregation, while the proton decreases
the rate of reduction and facilitates etching through the formation of nitric acid.
Nanocube Synthesis
www.angewandte.org
S. Kobatake,* Y. Matsumoto,
M. Irie*
2148 – 2151
Conformational Control of Photochromic
Reactivity in a Diarylethene Single Crystal
K. Takaoka, M. Kawano,* M. Tominaga,
M. Fujita*
2151 – 2154
In Situ Observation of a Reversible SingleCrystal-to-Single-Crystal Apical-LigandExchange Reaction in a Hydrogen-Bonded
2D Coordination Network
S. H. Im, Y. T. Lee, B. Wiley,
Y. Xia*
2154 – 2157
Large-Scale Synthesis of Silver
Nanocubes: The Role of HCl in Promoting
Cube Perfection and Monodispersity
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2049
Contents
Computer Chemistry
S.-D. Li,* J.-C. Guo, C.-Q. Miao,
G.-M. Ren
2158 – 2161
[(h6-B6X)2M] (X = C, N; M = Mn, Fe, Co,
Ni): A New Class of Transition-Metal
Sandwich-Type Complexes
Sandwich maker: A new class of transition-metal sandwich complexes [(h6B6X)2M] (X = C, N; M = Mn, Fe, Co, Ni) is
predicted by density functional calculations. The results suggest that salts of
transition-metal complexes containing
carbon atoms in a planar hexacoordinate
environment might be synthesized and
characterized (see picture; B red, C gray,
Fe blue, H white).
Service
Keywords
2162
Authors
2163
Angewandte’s Sister Journals
2164
Preview
2165
Corrigendum
*
Chasing Molecules That Were Never
There: Misassigned Natural Products
and the Role of Chemical Synthesis in
Modern Structure Elucidation
Irony is the comic relief of life. Either that or we must admit embarrassment about
misdrawing structure 1 (the structure proposed by Wieland and Windaus for
cholesterol) in this Review. We thank Prof. Dr. R. W. Hoffmann for politely pointing out
to us one additional means by which one can chase a molecule that was never there.
K. C. Nicolaou,* S. A. Snyder 1012–1044
Angew. Chem. Int. Ed. 2005, 44
DOI 10.1002/anie.200460864
2050
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
Angew. Chem. Int. Ed. 2005, 44, 2042 – 2050
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