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Graphical Abstract Angew. Chem. Int. Ed. 152005

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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 Semisynthetic 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
Awards of the Chemical Society of Japan 2004
2180
Books
Protein Synthesis and Ribosome Structure
Knud H. Nierhaus, Daniel N. Wilson
reviewed by M. Sprinzl
2182
High-Throughput Screening in Chemical
Catalysis
Alfred Hagemeyer, Peter Strasser,
Anthony F. Volpe, Jr.
reviewed by C. Markert
2183
Sweet developments: Proline-catalyzed
aldol reactions readily allow access to
complex carbohydrates from simple
glycolaldehydes in a highly stereoselective
fashion (see scheme; Bn = benzyl).
Made to measure: Nanostructuring of
surfaces is important for the activity of
catalysts in the conversion of fuels and in
electrochemistry. Particular care must be
taken to ensure the optimal particle size in
the nanometer range. The picture shows a
new method for the colloidal synthesis of
platinum and platinum-alloy nanoparticles of defined dimensions.
Highlights
Carbohydrate Synthesis
U. Kazmaier*
2186 – 2188
Amino Acids—Valuable Organocatalysts
in Carbohydrate Synthesis
Reviews
Nanotechnology
F. Raimondi, G. G. Scherer, R. Ktz,
A. Wokaun*
2190 – 2209
Nanoparticles in Energy Technology:
Examples from Electrochemistry and
Catalysis
2170
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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Angew. Chem. Int. Ed. 2005, 44, 2170 – 2178
Angewandte
Chemie
Communications
Azide–Alkyne Cycloadditions
V. O. Rodionov, V. V. Fokin,*
M. G. Finn*
2210 – 2215
A powerful engine: The Cu-catalyzed
azide–alkyne cycloaddition depends on
rapid formation of CuI–acetylide complexes from terminal alkynes 2 and their
ability to activate organic azides 1. A
kinetics study uncovered a bimolecular
dependence on the metal and an unusually fast intramolecular variant of the
process. The results suggest the importance of 3 as a reactive intermediate.
Mechanism of the Ligand-Free
CuI-Catalyzed Azide–Alkyne
Cycloaddition Reaction
Azide–Alkyne Cycloadditions
S. Punna, J. Kuzelka, Q. Wang,
M. G. Finn*
2215 – 2220
Head-to-Tail Peptide Cyclodimerization
by Copper-Catalyzed Azide–Alkyne
Cycloaddition
Rings forged with copper: Oligopeptide
cyclodimerization occurs selectively when
precursors containing azide and alkyne
groups are exposed to copper(i) ions on
polystyrene supports (see picture;
Prot = protecting group).
Monocarboranes
A. Laromaine, F. Teixidor,
C. Vias*
2220 – 2222
A nonclassical carbon atom of a dicarbaborane is converted into a classical carbon
atom, and the substituent increases in
length by one CH2 group (see scheme).
This is the path followed to form
[1-Me-6-Et-1-closo-CB9H8] regioselectively
from [1,2-Me2-1,2-closo-C2B10H10]. First,
the o-carborane derivative is reduced to
[7-Me-m-(9,10-HMeC)-7-nido-CB10H11] ,
and then a carbon-atom extrusion followed by selective deboronation takes
place.
Carbon Extrusion in 1,2-Dicarba-closododecaboranes: Regioselective
Boron Substitution in Ten-Vertex
closo-Monocarbaborane Anions
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Angew. Chem. Int. Ed. 2005, 44, 2170 – 2178
www.angewandte.org
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2171
Angewandte
Chemie
Relaxation time: Direct profiles of protein
1
H relaxation in D2O at mm concentrations were generated by NMR spectroscopy at 0.01–50 MHz (see picture). The
study of lysozyme at pH 3.5 (monomeric)
and pH 9.0 (dimeric), and of a-synuclein
(unfolded), provides direct information
on aggregation through estimates of the
realignment correlation time and on the
overall compactness of the protein.
Acid-specific conformational changes:
Protonation of meso-aryl-substituted
rubyrin 1 with HCl or CF3CO2H causes
different conformational changes, as
revealed by specific shifts in the UV/Vis
absorption bands relative to those of the
free-base form (Cl : blue shift; CF3CO2 :
red shift). The distinct counteraniondependent color changes upon addition
of the acids to the “anion sensor” 1 are
easily detected.
A five-membered metallacycle (2+)
hydrogenated at the 4-position of the
naphthyridine ligand results from the
reduction of [Ru(bpy)2(napy-kN)(CO)]2+
(12+; bpy = 2,2’-bipyridine, napy = 1,8naphthyridine) at 1.40 V in H2O.
Chemical or electrochemical oxidation
of 2+ regenerates 12+ in almost
quantitative yield.
Protein Dynamics
I. Bertini,* Y. K. Gupta, C. Luchinat,
G. Parigi, C. Schlrb,
H. Schwalbe
2223 – 2225
NMR Spectroscopic Detection of Protein
Protons and Longitudinal Relaxation
Rates between 0.01 and 50 MHz
Expanded Porphyrins
S. Shimizu, R. Taniguchi,
A. Osuka*
2225 – 2229
meso-Aryl-Substituted
[26]Hexaphyrin(1.1.0.1.1.0) and
[38]Nonaphyrin(1.1.0.1.1.0.1.1.0) from
Oxidative Coupling of a Tripyrrane
Redox Chemistry
T. Tomon, T.-a. Koizumi,
K. Tanaka*
2229 – 2232
Electrochemical Hydrogenation of
[Ru(bpy)2(napy-kN)(CO)]2+: Inhibition of
Reductive RuCO Bond Cleavage by a
Ruthenacycle
Asymmetric Synthesis
K. Biswas, O. Prieto, P. J. Goldsmith,
S. Woodward*
2232 – 2234
Weigh it out in air! The DABAL reagent
(Me3Al)2·(DABCO) (DABCO = 1,4diazabicyclo[2.2.2]octane) can be easily
handled under normal laboratory conditions. Furthermore, chiral secondary
alcohols can be efficiently prepared from
Angew. Chem. Int. Ed. 2005, 44, 2170 – 2178
prochiral aldehydes (see scheme; TOF =
turnover frequency) by using either
DABAL or AlR3 reagents (R = Me, Et).
Thus, DABAL can be used as an efficient,
convenient alternative to the Schumann–
Blum reagent.
www.angewandte.org
Remarkably Stable (Me3Al)2·DABCO and
Stereoselective Nickel-Catalyzed AlR3
(R = Me, Et) Additions to Aldehydes
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2173
Contents
Asymmetric Synthesis
P. J. Goldsmith, S. J. Teat,
S. Woodward*
2235 – 2237
Enantioselective Preparation of b,bDisubstituted a-Methylenepropionates by
MAO Promotion of the Zinc Schlenk
Equilibrium
Supramolecular Chemistry
N. L. Toh, M. Nagarathinam,
J. J. Vittal*
2237 – 2241
Topochemical Photodimerization in the
Coordination Polymer [{(CF3CO2)(m-O2CCH3)Zn}2(m-bpe)2]n through SingleCrystal to Single-Crystal Transformation
The zinc Schlenk equilibrium, little used
since it was first described in 1966, has
been promoted through the addition of
methylaluminoxane (MAO) to maximize
the yield of ZnR2 from deleterious RZnCl
by-products. This process allows an SN2’addition approach to the preparation of
chiral b,b-disubstituted a-methylenepropionates with high enantioselectivity (see
scheme).
The molecular-ladder-structured, onedimensional Zn–(4,4’-bipyridylethylene)
coordination polymer 1 undergoes [2þ2]
photochemical cycloaddition across the
rails to form 2 in up to 100 % yield,
accompanied by a single-crystal to singlecrystal transformation.
Supported Catalysts
S. Carrettin, J. Guzman,
A. Corma*
2242 – 2245
Supported Gold Catalyzes the
Homocoupling of Phenylboronic Acid
with High Conversion and Selectivity
Gold on nanocrystalline cerium oxide is a
highly active and selective catalyst for the
homocoupling of phenylboronic acid
derivatives in the presence of K2CO3 as a
base (see picture). Au3+ species are
b-Selective Glycosidation
R. Arihara, S. Nakamura,
S. Hashimoto*
2245 – 2249
Direct and Stereoselective Synthesis of 2Acetamido-2-deoxy-b-d-glycopyranosides
by Using the Phosphite Method
2174
Avoiding the intermediate: The b-selective
glycosidation of 2-acetamido-2-deoxyglycosyl diethyl phosphites promoted by
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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thought to be the active sites for the
reaction, and water is required to activate
the boronic acid through the participation
of surface hydroxy groups.
bis(trifluoromethanesulfonyl)imide
(Tf2NH) proceeds in a direct manner and
does not afford an oxazolinium ion as an
intermediate (see scheme; MS (4) = 4-
molecular sieves).
Angew. Chem. Int. Ed. 2005, 44, 2170 – 2178
Angewandte
Chemie
Library Synthesis
C. Chen, X. Li, C. S. Neumann,
M. M.-C. Lo,
S. L. Schreiber*
2249 – 2252
Convergent Diversity-Oriented Synthesis
of Small-Molecule Hybrids
Complex small-molecule libraries were
constructed by a convergent approach
with a short linear sequence: a 480membered bridged-piperidine/fused-pyrrolidine hybrid library IV and a 384-
π* (Fe-O)
no (Fe-Por)
Fe(dxz/yz)
no porphyrin π
π (Fe-O)
π* (Fe-Por)
O(px/y)
Por(3eg)
π (Fe-O)
π (Fe-Por)
membered spirocyclic-oxindole/fusedpyrrolidine hybrid library V from the sublibrary II and the sublibraries I and III,
respectively. II = RIICOOH.
Extremely similar electronic structures
and FeO bonding characterize FeIV=O
S = 1 heme and non-heme species as a
result of a decoupling of the oxoiron unit
from the porphyrin (Por) p system in the
heme complex (see scheme). However,
along the reaction coordinate towards an
FeIIIOH product, the Por p system interacts with the iron d orbitals, thus resulting
in different reactivities for heme and nonheme complexes.
Oxoiron (iv) Complexes
A. Decker, E. I. Solomon*
2252 – 2255
Comparison of FeIV=O Heme and
Non-heme Species: Electronic Structures,
Bonding, and Reactivities
Oxoiron(iv) Complexes
J.-U. Rohde, L. Que, Jr.*
2255 – 2258
Axial Coordination of Carboxylate
Activates the Non-heme FeIV=O Unit
Enhancing reactivity: A common feature
of non-heme iron enzymes is the presence
of carboxylate groups. An axial carboxylate
group has been introduced trans to the
oxo group of a non-heme oxoiron(iv)
complex (see scheme). The coordination
of carboxylate destabilizes the FeIV=O unit
and activates it towards reaction with
dihydroanthracene.
Asymmetric Synthesis
Unusual substrates for cascade reactions:
Racemic b-ketoesters with all-carbon
quaternary centers were used as starting
materials in a dynamic kinetic resolution
process to produce complex polycycles in
high enantio- and diastereoselectivities
(see scheme; TBS = tert-butyldimethylsilyl). The cascade reactions involved
epimerization in the second step through
the formation and cleavage of multiple
CC bonds in a retro-aldol/aldol equilibrium.
Angew. Chem. Int. Ed. 2005, 44, 2170 – 2178
K. Xu, G. Lalic, S. M. Sheehan,
2259 – 2261
M. D. Shair*
Dynamic Kinetic Resolution during a
Cascade Reaction on Substrates with
Chiral All-Carbon Quaternary Centers
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2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2175
Contents
Chiral Fullerene Adducts
S. Kuwahara, K. Obata, K. Yoshida,
T. Matsumoto, N. Harada,* N. Yasuda,
Y. Ozawa, K. Toriumi
2262 – 2265
Conclusive Determination of the Absolute
Configuration of Chiral C60-Fullerene cis-3
Bisadducts by X-ray Crystallography and
Circular Dichroism
Ultrathin red plate crystals of a chiral C60fullerene cis-3 bisadduct were subjected to
X-ray crystallographic analysis to finally
determine the absolute configuration of
such an adduct conclusively (see picture;
C gray, O red, H blue). A comparison of
its circular-dichroism spectrum with those
of similar compounds suggested that the
absolute configurations reported for some
compounds may require revision.
Colorimetric Sensors
M. Maue, T. Schrader*
Right in front of your eyes: Upon addition
of a catecholamine to a catechol-containing receptor precomplexed with a dye, a
change in color from orange to deep red
signals the release of the dye and capture
of the guest (see picture). This simple
competition experiment allows exact
quantitative determination of the concentration of catecholamines in complex
mixtures, such as that of adrenaline in
urine samples.
2265 – 2270
A Color Sensor for Catecholamines
Nucleic Acid Structure
String quartets: Guanine molecules
self-assemble into a hydrogen-bonded
network of G quartets upon deposition
under ultrahigh vacuum conditions onto
Au(111) surfaces as shown by STM (see
picture). The resilience of the H-bonded
network (stable up to 400 K) is explained
through a cooperative increase in the
strength of H-bonds between guanine
molecules in a quartet.
R. Otero, M. Schck, L. M. Molina,
E. Lægsgaard, I. Stensgaard, B. Hammer,
F. Besenbacher*
2270 – 2275
Guanine Quartet Networks Stabilized by
Cooperative Hydrogen Bonds
Helical Structures
A. J. Wilson, M. Masuda, R. P. Sijbesma,*
E. W. Meijer*
2275 – 2279
Chiral Amplification in the Transcription
of Supramolecular Helicity into a
Polymer Backbone
2176
A chiral supramolecular “sergeant” as the
structure-directing agent affects the
backbone stereochemistry during polymerization of the achiral “soldier”
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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monomers. The polymer obtained shows
preferred helical folding despite its mixed
microstructure.
Angew. Chem. Int. Ed. 2005, 44, 2170 – 2178
Angewandte
Chemie
Solid-State Reactions
C. Hu, U. Englert*
Zipping in an extra dimension: In the
coordination polymer [ZnCl2(m-bipy)]¥
one-dimensional chains (left) switch into
a two-dimensional network (right) in the
solid at a surprisingly low temperature of
2281 – 2283
Crystal-to-Crystal Transformation from a
Chain Polymer to a Two-Dimensional
Network at Low Temperatures
130 K. At temperatures above 360 K the
reverse transformation takes place. The
reaction occurs in single crystals as well
as in powders. bipy = 4,4’-bipyridine.
Molecular Switches
A vitamin that switches states: The
appended nucleotide base B assists in the
constitutional switch from the base-on
form of the B12 conjugate (blue, with a
coordinated 5,6-dimethylbenzimidazole
(DMB) unit) to the base-off form (red,
with a free DMB unit). The process is
strongly temperature dependent.
S. Gschsser, K. Gruber, C. Kratky,*
C. Eichmller, B. Krutler*
2284 – 2288
B12-retro-Riboswitches: Constitutional
Switching of B12 Coenzymes Induced by
Nucleotides
Photoreceptor Mimetics
Molecular lamps: Analogously to a lamp
with a light bulb, a switch, and a plug, the
fluorescent ON state of dyad 1 can be
blocked by other means besides the light
switch (“removing the plug”). By using
flavin as a redox unit and thermal or UVactivated thiol/disulfide redox chemistry,
one can switch between the oxidized and
reduced forms of the dyad (see picture).
The reaction is reminiscent of the LOV
domains of blue-light photoreceptors
such as the phototropins.
C. Trieflinger, K. Rurack,*
J. Daub*
2288 – 2291
“Turn ON/OFF your LOV light”:
Borondipyrromethene–Flavin Dyads as
Biomimetic Switches Derived from the
LOV Domain
Green Chemistry
M. Solinas, J. Jiang, O. Stelzer,
W. Leitner*
2291 – 2295
A judicious combination of an organometallic catalyst and workup with supercritical CO2 resulted in a recyclable system
for mediating a variety of transformations.
Between reactions the catalyst is “switched off” and recovered as a precipitate
from the reaction mixture when scCO2 is
Angew. Chem. Int. Ed. 2005, 44, 2170 – 2178
introduced. Simultaneously the product is
isolated by extraction with scCO2. The key
is the unique solubility properties of the
Rh catalyst arising from the poly(ethyleneglycol) chains in the phosphine
ligands (see scheme).
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A Cartridge System for Organometallic
Catalysis: Sequential Catalysis and
Separation Using Supercritical Carbon
Dioxide to Switch Phases
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2177
Contents
Natural Product Synthesis
D. E. N. Jacquot, M. Zllinger,
T. Lindel*
2295 – 2298
Total Synthesis of the Marine Natural
Product rac-Dibromophakellstatin
The pyrrole-imidazole alkaloid dibromophakellstatin (1) from the marine sponge
Phakellia mauritiana was synthesized in
only five steps starting from l-prolinol.
The key step of the synthesis is the direct
annulation of the imidazolinone ring to a
pyrrolopyrazinone precursor by employing
an ethoxycarbonylnitrene generated in
situ. Samarium diiodide proved to be the
best choice for the chemoselective, stepwise deprotection of the resulting tetracycle. Ts = toluenesulfonyl.
Service
Keywords
2300
Authors
2301
Preview
2303
Corrigendum
*
Halide Recognition through Diagnostic
“Anion–p” Interactions: Molecular
Complexes of Cl, Br, and I with
Olefinic and Aromatic p Receptors
Y. S. Rosokha, S. V. Lindeman,
S. V. Rosokha, J. K. Kochi
4650–4652
In this Communication, the authors inadvertedly omitted an acknowledgement. It
should read: “We thank D. K. Kim for providing the crystal of the charge-transfer
complex o-chloranil/tetra-n-propylammonium bromide in Table 1 as well as spectral
data relating to the o-chloranil acceptor in Figure 1. We are also grateful to M. G.
Davlieva for providing the crystal of the tetracyanopyrazine/tetra-n-butylammonium
iodide complex. We thank the R. A. Welch Foundation and the National Science
Foundation for financial support.”
Angew. Chem. Int. Ed. 2004, 43
DOI 10.1002/anie.200460337
2178
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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Angew. Chem. Int. Ed. 2005, 44, 2170 – 2178
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