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Graphical Abstract Angew. Chem. Int. Ed. 212006

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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:
C. Burke, Y. Shi*
Regio- and Enantioselective Epoxidation of Dienes by a Chiral
Dioxirane: Synthesis of Optically Active Vinyl cis-Epoxides
C.-W. So, H. Roesky,* J. Magull, R. Oswald
Synthesis and Characterization of [{PhC(NtBu)2}SiCl]: A Stable
Monomeric Chlorosilylene
H. Yu, S. Huang, H. Chokhawala, M. Sun, H. Zheng, X. Chen*
Highly Efficient Chemoenzymatic Synthesis of Naturally
Occurring and Non-Natural a2,6-Linked Sialosides: A
P. damsela a2,6-Sialyltransferase with Extremely Flexible Donor
Substrate Specificity
D. Rohde, C.-J. Yan, H.-J. Yan, L.-J. Wan*
From Lamellar to Hexagonal Self-Assembly of Bis(dioxaborin)
Molecules
News
Inorganic Chemistry:
Nth Recognized
3398
Biophysics:
Sackmann Honored
3398
Biochemistry:
Davies Awarded
3398
Books
Six-Membered Hetarenes with One
Nitrogen or Phosphorus Atom
D. St. C. Black
reviewed by C. Marazano
3399
The Organic Chemistry of Sugars
Daniel E. Levy, P-ter F/gedi
reviewed by V. Wittmann
3399
Highlights
Water Anomalies
R. Ludwig*
3402 – 3405
The Puzzling Properties of Supercooled
and Glassy Water
Cold as ice: The anomalies in the properties of water arise from a transformation
between two major liquid forms of water
in the deeply supercooled region which
are proposed to meet at a liquid–liquid
critical point. Recent studies of glassy
and supercooled water give insight into
water’s unusual phase-transition
behavior.
Essays
Design in Chemistry
M. Jansen,* J. C. Schn
3406 – 3412
“Design” in Chemical Synthesis—An
Illusion?
3386
The power of words: According to its
generally accepted definition, the process
of “design” is the creation of a form that
fulfills a given function as well as possible
and is also considered aesthetically
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
pleasing. This implies a type of creativity
that does not exist in the synthesis of new
chemical compounds. This essay discusses the implications of the term “design”
in the context of chemistry.
Angew. Chem. Int. Ed. 2006, 45, 3386 – 3396
Angewandte
Chemie
Reviews
Nanoparticle Synthesis
Nanocrystals get into shape: Recent
developments in the shape control of
semiconductor and metal oxide nanocrystals have yielded many structurally
unprecedented nanocrystals including
polyhedrons, rods, wires, plates, prisms,
and other complex shapes (see picture).
Such specially shaped nanocrystals exhibit novel properties and can be further
utilized as key building blocks for the
fabrication of nanosystems.
Y.-w. Jun, J.-s. Choi,
J. Cheon*
3414 – 3439
Shape Control of Semiconductor and
Metal Oxide Nanocrystals through
Nonhydrolytic Colloidal Routes
Communications
Supersonic jet expansions of racemic
methyl lactate show a prominent OHstretching infrared absorption at
3401 cm 1 which is not present in the
enantiopure compound. Experimental
results and quantum chemical calculations show that the underlying tetrameric
cluster has 2:2 stoichiometry of the R and
S isomers and S4 symmetry (see picture;
C orange, O red, H gray).
Chiral Recognition
T. B. Adler, N. Borho, M. Reiher,
M. A. Suhm*
3440 – 3445
Chirality-Induced Switch in HydrogenBond Topology: Tetrameric Methyl Lactate
Clusters in the Gas Phase
Homogeneous catalysis
Going ferryl: FeII complexes with two
isomeric bispidine ligands catalyze the
oxidation of cyclooctene with H2O2 in
MeCN under aerobic conditions with high
selectivity for the epoxide (see scheme;
L = bispidine ligand). An {FeIV=O} com-
plex is postulated to be the oxidant,
formed by the homolytic cleavage of the
O O bond of an {FeIII-OOH} intermediate. Performing the reaction under argon
gives a mixture of cis and trans diols as
well as the epoxide.
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Chemie, Wiley-VCH, 111 River Street, Hoboken,
NJ 07030. Annual subscription price for institutions: US$ 5685/5168 (valid for print and
Angew. Chem. Int. Ed. 2006, 45, 3386 – 3396
M. R. Bukowski, P. Comba,* A. Lienke,
C. Limberg, C. Lopez de Laorden,
R. Mas-Ballest-, M. Merz,
L. Que, Jr.*
3446 – 3449
Catalytic Epoxidation and 1,2Dihydroxylation of Olefins with Bispidine–
Iron(ii)/H2O2 Systems
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individuals who are personal members of a
national chemical society prices are available
on request. Postage and handling charges
included. All prices are subject to local VAT/
sales tax.
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
3387
Angewandte
Chemie
Bound to succeed: Noncovalent binding
of ligands to RNA can be analyzed easily
by 19F NMR spectroscopy through sitespecific fluorine-labeling of the target RNA
(see picture; B = adenine, cytosine, guanine, uracil). The proof of concept is
provided by RNA aptamer–ligand interactions. The speed and the robustness of
this simple approach present major
advantages over methods relying on
1
H NMR spectroscopy.
Drug Design
C. Kreutz, H. KRhlig, R. Konrat,*
R. Micura*
3450 – 3453
A General Approach for the Identification
of Site-Specific RNA Binders by 19F NMR
Spectroscopy: Proof of Concept
Enzymatic Syntheses
T. Purkarthofer, K. Gruber,
M. Gruber-Khadjawi, K. Waich, W. Skranc,
D. Mink, H. Griengl*
3454 – 3456
Novel enzyme activity: Biocatalytic Henry
reactions with nitromethane and nitroethane yielded the corresponding nitroalcohols with good enantio- and diastereocontrol in the presence of the hydroxy-
nitrile lyase from the tropical rubber tree
Hevea brasiliensis. Molecular modeling
and deuterated starting materials were
used in mechanistic investigations.
A Biocatalytic Henry Reaction—The
Hydroxynitrile Lyase from Hevea
brasiliensis Also Catalyzes Nitroaldol
Reactions
Solid-State Structures
C. Hu, U. Englert*
Three structures for the price of one: The
room-temperature phase of the 2D
network [Pb(m-Cl)2(m-bipy)]¥ (bipy = 4,4’bipyridine) undergoes crystal-to-crystal
transformations both upon cooling (see
picture; Pb pink, Cl green, N blue, C gray,
H white) and upon heating. With increasing temperature, decreased packing
efficiency is traded for higher symmetry.
Closed encounters: A closed deltahedral
homoatomic cluster, [Pb10]2 , is
structurally characterized. When this
“empty” cluster is considered together
with the recently published filled cluster
[Ni@Pb10]2 , a striking parallel to the
fullerenes emerges: Zintl ions form
polyhedral cages that can enclose a
central atom without any major structural
alterations.
Angew. Chem. Int. Ed. 2006, 45, 3386 – 3396
3457 – 3459
Space Filling Versus Symmetry: Two
Consecutive Crystal-to-Crystal Phase
Transitions in a 2D Network
“Empty” Metal Clusters
A. Spiekermann, S. D. Hoffmann,
T. F. FRssler*
3459 – 3462
The Zintl Ion [Pb10]2 : A Rare Example of a
Homoatomic closo Cluster
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
3389
Contents
C H Activation
H. Ren, P. Knochel*
3462 – 3465
Chemoselective Benzylic C H Activations
for the Preparation of Condensed
N-Heterocycles
Molecular Dynamics
M. Schnell, J.-U. Grabow*
3465 – 3470
Multidimensional Large-Amplitude
Motion: Revealing Concurrent Tunneling
Pathways in Molecules with Several
Internal Rotors
Buttoning up: A chemoselective domino
reaction including one or two successive
C H activations serves to convert a range
of readily available N-arylpyrroles into
complex polycondensed N-heterocycles.
The reaction is catalyzed by Pd(OAc)2
(5 mol %), and p-Tol3P (10 mol %) is
added as the ligand (see scheme;
Tol = tolyl).
Light at the end of the tunnel: Knowledge
of the feasible tunneling pathways of a
molecule can shed light on the interaction
mechanisms that govern its internal
dynamics. A combination of rotational
spectroscopy, permutation inversion
group theory, and multidimensional tunneling formalism has shown that in the
series (CH3)3XCl (X = Si, Ge, Sn), electrostatic repulsion is gradually reduced and
the chemical bond gains importance.
Rotational Spectroscopy
Expanding the possibilities: The hydration
of glycine has been observed in a supersonic jet by using laser ablation in combination with Fourier transform microwave spectroscopy. The rotational spectrum reveals that water binds to glycine
through two hydrogen bonds, which
bridge the carboxylic acid group in a
closed planar structure. In the complex,
glycine retains the most stable conformer
of the parent unhydrated molecule.
J. L. Alonso,* E. J. Cocinero, A. Lesarri,
M. E. Sanz, J. C. LWpez
3471 – 3474
The Glycine–Water Complex
Main-Group Hydrides
S. Harder,* J. Brettar
3474 – 3478
Rational Design of a Well-Defined Soluble
Calcium Hydride Complex
3390
www.angewandte.org
A surprisingly simple approach led to the
synthesis of a molecular calcium hydride.
Reaction of a calcium amide with phenylsilane gives clean conversion into the
hydride that crystallizes as a dimer (see
structure).
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Angew. Chem. Int. Ed. 2006, 45, 3386 – 3396
Angewandte
Chemie
Asymmetric Catalysis
Y. Sawada, K. Matsumoto, S. Kondo,
H. Watanabe, T. Ozawa, K. Suzuki,
B. Saito, T. Katsuki*
3478 – 3480
Keep it simple: A titanium complex with a
salan ligand bearing phenyl groups at C3
and C3’ is an efficient catalyst for the
enantioselective epoxidation of unfunctionalized olefins with aqueous hydrogen
peroxide (see scheme); furthermore, the
epoxidation was stereospecific. The C3
and C3’ substituents stabilize this
complex and enhance the asymmetric
induction.
Titanium–Salan-Catalyzed Asymmetric
Epoxidation with Aqueous Hydrogen
Peroxide as the Oxidant
Planar Chirality
B. Jacques, M. Chavarot, F. Rose-Munch,*
E. Rose
3481 – 3484
Easy does it: A lithiation/electrophilic
quench sequence gives efficient access to
a large variety of unprecedented complexes. One such complex (1; see scheme)
can be successfully used in the synthesis
of the first enantiopure formyl-substituted
[(h5-cyclohexadienyl)Mn(CO)3] derivatives.
Lithiation/Electrophilic Quench of
[(h5-Cyclohexadienyl)Mn(CO)3]: Versatile
Functionalization and Resolution of
Planar Chirality in the Organomanganese
Series
Coupling Reactions
Unprecedented activity: Catalysts derived
from Pd and bulky dialkylphosphinobiaryl
ligands are shown to be highly stable and
active in Suzuki–Miyaura reactions of
heteroaryl halides and heteroaryl boronic
A quick fix: In contrast to cyclic diamino
carbenes, stable alkyl amino carbenes
react with CO to give stable ketenes (see
scheme, top). Contrary to the acyclic
versions, cyclic amino ketenes cannot
escape from the destabilizing n–p donation of the nitrogen lone pair, which
induces a diradical character and unusual
optical (see scheme, bottom and photographs of crystals) and NMR spectroscopic properties.
Angew. Chem. Int. Ed. 2006, 45, 3386 – 3396
acids/esters (e.g., 3- or 4-pyridine, indole,
and N-protected pyrrole derivatives). Furthermore, this catalyst system is not
inhibited by the presence of highly basic
aminopyridines or aminopyrimidines.
K. L. Billingsley, K. W. Anderson,
S. L. Buchwald*
3484 – 3488
A Highly Active Catalyst for Suzuki–
Miyaura Cross-Coupling Reactions of
Heteroaryl Compounds
Carbenes
V. Lavallo, Y. Canac, B. Donnadieu,
W. W. Schoeller,
G. Bertrand*
3488 – 3491
CO Fixation to Stable Acyclic and Cyclic
Alkyl Amino Carbenes: Stable Amino
Ketenes with a Small HOMO–LUMO Gap
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
3391
Contents
Asymmetric Synthesis
H. Takikawa, Y. Hachisu, J. W. Bode,
K. Suzuki*
3492 – 3494
Catalytic Enantioselective Crossed
Aldehyde–Ketone Benzoin Cyclization
Oxidation
T. Ngouansavanh, J. Zhu*
3495 – 3497
Alcohols in Isonitrile-Based
Multicomponent Reaction: Passerini
Reaction of Alcohols in the Presence of
O-Iodoxybenzoic Acid
Microporous Materials
W. Ouellette, M. H. Yu, C. J. O’Connor,
D. Hagrman, J. Zubieta*
3497 – 3500
Hydrothermal Chemistry of the Copper–
Triazolate System: A Microporous Metal–
Organic Framework Constructed from
Magnetic {Cu3(m3-OH)(triazolate)3}2+
Building Blocks, and Related Materials
Hydrogen Storage
C. P. Bald-, B. P. C. Hereijgers, J. H. Bitter,
3501 – 3503
K. P. de Jong*
Facilitated Hydrogen Storage in NaAlH4
Supported on Carbon Nanofibers
3392
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2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Joining together: The catalytic, asymmetric benzoin cyclization of a wide variety
ketoaldehydes using chiral triazolium
salts of type 1 has been carried out (see
scheme). The corresponding cyclized
products were prepared in high yields and
with excellent enantioselectivities.
High proof: An alcohol instead of an
aldehyde is an effective reaction partner in
the Passerini reaction (P-3CR) in the
presence of O-iodoxybenzoic acid (IBX).
Thus, by simply heating a solution of an
alcohol, a carboxylic acid, an isonitrile,
and IBX at 40 8C, an oxidation/P-3CR
sequence occurred smoothly to afford the
a-acyloxy carboxamide in good-to-excellent yield.
Networking with triazolate: Three new
compounds containing networks of CuI or
CuII ions linked by 1,2,4-triazolate (trz)
ligands were prepared by hydrothermal
synthesis. The microporous metal–
organic framework {Cu3(m3-OH)(trz)3(OH)2(H2O)4}n, which is built up
from magnetic triangles, forms
17 Z 13 Z 13 [3 cavities (see picture;
Cu dark blue, O red, N light blue,
C black).
The ins and outs of hydrogen: The
hydrogen desorption from and absorption
to sodium alanate (NaAlH4) supported on
carbon nanofibers are significantly facilitated if its particle size is reduced from the
micrometer to the nanometer range (see
graph). This improvement is tentatively
attributed to the minimization of the
solid-state diffusion path length during
loading and desorption of hydrogen.
Angew. Chem. Int. Ed. 2006, 45, 3386 – 3396
Angewandte
Chemie
Protecting Groups
L. J. Ingram, S. D. Taylor*
Sweet sulfur: Sulfuryl imidazolium salt 1
represents a new class of highly potent
sulfating agents and is very effective for
introducing trichloroethyl-protected sulfates into monosaccharides for the
synthesis of sulfated oligosaccharides
(see scheme; NMI = N-methylimidazole,
OTf = triflate, PG = protecting group,
TCE = 2,2,2-trichloroethyl).
3503 – 3506
Introduction of 2,2,2-TrichloroethylProtected Sulfates into Monosaccharides
with a Sulfuryl Imidazolium Salt and
Application to the Synthesis of Sulfated
Carbohydrates
Biosynthesis
A. Chatterjee, X. Han, F. W. McLafferty,
T. P. Begley*
3507 – 3510
ThiS and that: An alternative substrate for
thiazole synthase, namely 1,4-dideoxy-dxylulose-5-phosphate, was synthesized
and used as a mechanistic probe to
determine the regiochemistry of the acyl-
shift reaction that occurs as an intermediate step in the biosynthesis of thiamin thiazole in B. subtilis (see scheme;
ThiS protein (blue); ThiG protein (red);
OP = phosphate group).
To rub gel into the wound: A thermoresponsive ABA triblock copolymer gelator
with A = N-isopropylacrylamide and B = 2(methacryloyloxy)ethyl phosphorylcholine
has been synthesized by atom transfer
radical polymerization by using a bifunctional disulfide-based initiator. This triblock copolymer forms free-standing
peptide-degradable micellar gels under
physiologically relevant conditions.
Biosynthesis of Thiamin Thiazole:
Determination of the Regiochemistry of
the S/O Acyl Shift by Using 1,4-Dideoxy-dxylulose-5-phosphate
Gels
C. Li, J. Madsen, S. P. Armes,*
A. L. Lewis
3510 – 3513
A New Class of Biochemically Degradable,
Stimulus-responsive Triblock Copolymer
Gelators
Boron Chemistry
D. L. Kays (n-e Coombs), J. K. Day,
S. Aldridge,* R. W. Harrington,
W. Clegg
3513 – 3516
It’s all new to B: In the reaction of
borylene complex 1 with benzophenone, a
Meerwein–Ponndorf b-hydride transfer
from the aminoborylene ligand to the
Angew. Chem. Int. Ed. 2006, 45, 3386 – 3396
coordinated ketone generates 2 (see
structure), the first example of an iminedonor-stabilized borylene complex, and
the first cationic alkoxyborylene system.
Cationic Terminal Borylene Complexes:
Interconversion of Amino and Alkoxy
Borylenes by an Unprecedented
Meerwein–Ponndorf
Hydride Transfer
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
3393
Contents
Host–Guest Chemistry
R. J. Hooley, S. M. Biros,
J. Rebek, Jr.*
3517 – 3519
A Deep, Water-Soluble Cavitand Acts as a
Phase-Transfer Catalyst for Hydrophobic
Species
Overcoming inhibition: A deep, watersoluble cavitand has been shown to
extract various N-substituted maleimides
into aqueous solution through the hydrophobic effect. These complexes react with
a water-soluble thiol to confer water
solubility to the product, thus leading to a
drastic reduction in binding affinity and
allowing this system to function as a
phase-transfer catalyst.
Sulfur Complexes
H. Sugimoto,* R. Tajima, T. Sakurai,
H. Ohi, H. Miyake, S. Itoh,
H. Tsukube
3520 – 3522
Reversible Sulfurization–Desulfurization
of Tungsten Bis(dithiolene) Complexes
Easy come, easy go: Tungsten bis(dithiolene) complexes undergo reversible sulfurization–desulfurization in which the
metal center changes between {WVI(S2)}
and {WV}. The process is effectively con-
trolled by the solution temperature, the
solvent, and the electron-donating properties of the dithiolene ligands and results
in a distinct color change (see scheme).
Making sense: A DNA hairpin was synthesized by attaching a 20-mer antisense
oligodeoxynucleotide (asODN) to a sense
ODN through a bifunctional photocleavable linker. This conjugate became much
less stable upon UV photoactivation
(DTm = 29 K, DDG = 4.6 kcal mol 1),
which facilitated binding of the asODN to
the complementary RNA. By this strategy,
photomodulation of RNase H activity
towards a variety of RNA targets was
performed.
DNA Structures
X. Tang, I. J. Dmochowski*
3523 – 3526
Controlling RNA Digestion by RNase H
with a Light-Activated DNA Hairpin
Colloids
U. T. Gonzenbach, A. R. Studart,*
E. Tervoort, L. J. Gauckler
3526 – 3530
Ultrastable Particle-Stabilized Foams
3394
www.angewandte.org
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Pump up the volume: Wet foams prepared with surfactants are thermodynamically unstable systems that undergo
rapid disproportionation, drainage, and
coalescence. Ultrastable foams have now
been prepared using colloidal particles as
stabilizers (left picture). The stabilization
results from the irreversible adsorption at
the air–water interface of particles surfacemodified with short-chain amphiphiles
(right picture).
Angew. Chem. Int. Ed. 2006, 45, 3386 – 3396
Angewandte
Chemie
DNA structure
Well protected: Porphyrins act as a molecular cap (see picture) to selectively
stabilize a non-self-complementary nonWatson–Crick DNA structure through
additional hydrophobic interactions. At
the same time, these porphyrins serve as
an efficient internal sensor of the newly
formed secondary structure.
M. Balaz,* B. C. Li, S. Jockusch,
G. A. Ellestad, N. Berova*
3530 – 3533
Tetraarylporphyrin as a Selective
Molecular Cap for Non-Watson–Crick
Guanine–Adenine Base-Pair Sequences
Biocatalyst Identification
M. Weis, E. K. Lim, N. Bruce,
D. Bowles*
3534 – 3538
A novel whole-cell screen for the identification of new glucosyltransferase (GT)
biocatalysts within a recombinant enzyme
library was developed. Following biotransformation, levels of d-glucose were
used as a measure of biocatalysis. Twenty
five enzymes that transfer d-glucose to
trans-resveratrol were identified that have
the regioselectivity shown in the picture.
Regioselective Glucosylation of Aromatic
Compounds: Screening of a Recombinant
Glycosyltransferase Library to Identify
Biocatalysts
Strength in numbers: Multivalent dendrons that have an N-maleimido group at
the focal point can be used to construct
monodisperse one-to-one protein–dendron conjugates. The second generation
polyamine dendron with spermine surface
groups clearly imparts its high-affinity
DNA binding to a protein of choice.
Protein Functionalization
Shake, rattle, and roll: As a guest within a
short-spaced cyclic dimer of an organorhodium porphyrin 1, fullerenes such as
C60 and C70 start to oscillate by slipping
through the host cavity. This dynamic
motion is substantially prohibited by
another molecule of 1 through the formation of capsule-type inclusion complexes. In contrast, a larger fullerene such
as C76 can hardly slip through the host
cavity but is simply encapsulated by two
molecules of 1.
Host–Guest Chemistry
M. A. Kostiainen,* G. R. Szilvay,
D. K. Smith,* M. B. Linder,
O. Ikkala
3538 – 3542
Multivalent Dendrons for High-Affinity
Adhesion of Proteins to DNA
A. Ouchi, K. Tashiro,* K. Yamaguchi,
T. Tsuchiya, T. Akasaka,
T. Aida*
3542 – 3546
A Self-Regulatory Host in an Oscillatory
Guest Motion: Complexation of
Fullerenes with a Short-Spaced Cyclic
Dimer of an Organorhodium Porphyrin
The issues for May 2006 appeared online on the following dates
Issue 17: April 11. · Issue 18: April 21. · Issue 19: April 27. · Issue 20: April 5
Angew. Chem. Int. Ed. 2006, 45, 3386 – 3396
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
3395
Contents
Service
Keywords
3548
Authors
3549
Angewandte’s
Sister Journals
3550 – 3551
Vacancies
3397
Preview
3553
For more information on
ChemMedChem see
www.chemmedchem.org
3396
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2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Angew. Chem. Int. Ed. 2006, 45, 3386 – 3396
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