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Graphical Abstract Angew. Chem. Int. Ed. 122003

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Contents
News
Protein Engineering: Alan Fersht
Knighted
1330
Polymers: Klaus Mllen
Recognized
1331
Guy Bertrand
1330
Cover Pictures 2002:
The Winners
1330
Books
Carbene Chemistry
reviewed by W. Kirmse
Highlights
OMe
Controlled Cycloadditions
Cr(CO)5
F. Zaragoza D'rwald*
1332 – 1334
MeO
MeO
R
+
OMe
R
Solvent-Controlled Selectivity in the
Synthesis of Five-Membered Carbocycles
from Carbene Complexes
R
Surprisingly different products can be
obtained from Fischer-type alkenyl carbene complexes and 1,3-dienes. The
choice of solvent and reaction temper-
Si
Si
Agostic Interactions
LnM
G. I. Nikonov*
R
Cr(CO)5
1335 – 1337
+
LnM
Si
Si
Si
Complexation of SiSi s Bonds to Metals
LnM
Si
The long-known class of nonclassical
complexes containing agostic interactions, XH!M, and coordinated
ature is of critical importance for the
outcome of these reactions, but the
reasons for the variable results remain far
from being understood.
s bonds, (XH)!M, has recently been
joined by a new group of “hydrogen-free”
compounds that exhibit (XY)!M interactions. In addition to those complexes
with agostic CC and CSi bonding, the
first SiSi s complexes (see scheme) of
group 5 and group 10 transition-metal
elements have been prepared, and their
relevance towards SiSi bond-coupling
reactions has been established.
Reviews
Rare-Earth Elements
K. Dehnicke,* A. Greiner
1340 – 1354
Unusual Complex Chemistry of Rare-Earth
Elements: Large Ionic Radii—Small
Coordination Numbers
1322
Ligands slim down: Complexes of rareearth elements with low coordination
numbers for the metal centers can be
obtained in the “classical way” by using
bulky ligand groups. Recently, they were
prepared in a reaction with the slender
phosphoraneiminato ligand NPR3 (see
picture) which protects the metal center
on account of metal-nitrogen multiple
bonding. These complexes are very
efficient catalysts for ring-opening
polymerization of lactones.
2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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Angew. Chem. Int. Ed. 2003, 42, No. 12
Angewandte
Chemie
Communications
Protease Inhibitors
Y. S. Tsantrizos,* G. Bolger, P. Bonneau,
D. R. Cameron, N. Goudreau, G. Kukolj,
S. R. LaPlante, M. LlinAs-Brunet, H. Nar,
D. Lamarre
1356 – 1360
Macrocyclic Inhibitors of the NS3
Protease as Potential Therapeutic Agents
of Hepatitis C Virus Infection
Clinically useful antiviral agents for the
treatment of hepatitis C viral infections
might be derived from the here presented
macrocyclic inhibitors (right) of the hepatitis C virus (HCV) NS3 protease. The
NMR-derived conformation of a substrate-based enzyme-bound hexapeptide
(left) was used to design these inhibitors.
These are the first inhibitors of NS3
protease which block HCV RNA replication in the cell-based replicon assay, they
are orally absorbed, and they are stable to
metabolic breakdown.
Supramolecular Inclusion Compounds
Be my guest: A new family of supramolecular inclusion compounds is
introduced which relies upon secondsphere hydrogen-bonding interactions to
assemble highly stable layered networks
(see picture). These solids have great
potential for structural variation. They are
possibly inorganic analogues of a wellstudied host family, the guanidinium
sulfonates.
D. S. Reddy, S. Duncan,
G. K. H. Shimizu*
1360 – 1364
A Family of Supramolecular Inclusion
Solids Based Upon Second-Sphere
Interactions
Ni-Catalyzed Multicomponent Reaction
S. J. Patel, T. F. Jamison*
1364 – 1367
An unusual degree of functional group
compatibility for imine addition reactions
was observed in the assembly of allylic
amines from alkynes, imines, and organoboron reagents (boronic acids or bor-
anes) by using a catalyst derived from
[Ni(cod)2] and (c-C5H9)3P—this catalytic
three-component process (see scheme) is
tolerant of ketones, esters, and hydroxylic
solvents.
Catalytic Three-Component Coupling of
Alkynes, Imines, and Organoboron
Reagents
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Angew. Chem. Int. Ed. 2003, 42, 1322 – 1328
2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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1323
Contents
Asymmetric Amination
M. Marigo, K. Juhl,
K. A. Jørgensen*
1367 – 1369
Catalytic, Highly Enantioselective, Direct
Amination of b-Ketoesters
Optically active a-amino acid derivatives
were accessed through the direct asymmetric a-amination of a-substituted
b-ketoesters 1, catalyzed by chiral CuII–
bisoxazoline (BOX) complexes. The reac-
tion proceeds with dibenzyl azodicarboxylate in the presence of only 0.2 mol % of
the catalyst to give the desired products 2
in high yield with excellent enantioselectivity (up to 99 % ee).
Reactivity can be rationally manipulated in
DNA-templated synthesis by altering the
design of template architectures: a) The
omega (W) architecture enables DNAtemplated reactions to be encoded by
bases distal from the reactive end of the
template, regardless of the distance
dependence of the reaction. b) The
T architecture enables two DNA-templated reactions to take place on a single
template in one solution, as illustrated.
Superparamagnetic nanosensors conjugated to avidin (CLIO-A) can be used to
measure sensitively and quantitively the
proteolytic cleavage of bi-biotinylated
peptide substrates (rods in the scheme)
by changes in magnetic resonance properties. This approach may be generalized
to determine the activity of a wide range of
hydrolytic enzymes.
Excellent enantioselectivity (up to
96 % ee) was attained in an antibodycatalyzed photochemical Norrish type II
reaction, which proceeded via the intermediate diradical 1 to produce the cyclobutanols 4 (absolute stereochemistry
unknown). Use of the antibody was shown
to alter the course of the reaction by
favoring formation of the cyclization
product 4 over the fragmentation products 2 and 3.
DNA-Templated Synthesis
Z. J. Gartner, R. Grubina, C. T. Calderone,
D. R. Liu*
1370 – 1375
Two Enabling Architectures for DNATemplated Organic Synthesis
Superparamagnetic Nanosensors
M. Zhao, L. Josephson, Y. Tang,
R. Weissleder*
1375 – 1378
Magnetic Sensors for Protease Assays
Biocatalysis in Photochemistry
S. Saphier, S. C. Sinha,
E. Keinan*
1378 – 1381
Antibody-Catalyzed Enantioselective
Norrish Type II Cyclization
1324
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Angew. Chem. Int. Ed. 2003, 42, No. 12
Angewandte
Chemie
Biocatalyst Design
A. Esposito, E. Delort, D. Lagnoux,
F. Djojo, J.-L. Reymond*
1381 – 1383
Catalytic Peptide Dendrimers
A2, A3 = His, Asp, Ser), and a disulfide
bond dimerization strategy. All possible
permutations of the catalytic triad of the
amino acids aspartate, histidine, and
serine at the variable positions gave a
family of 21 peptide dendrimers.
Enzymelike kinetics were observed in the
hydrolysis of 7-hydroxy-1-methylquinolium esters 2 under the catalysis of three
of a family of synthetic peptide dendrimers 1. Their synthesis was based on a
symmetrical branching diamino acid (B),
three variable amino acid positions (A1,
Dynamic Self-Assembled Materials
L. Pirondini, A. G. Stendardo, S. Geremia,
M. Campagnolo, P. SamorS, J. P. Rabe,
R. Fokkens, E. Dalcanale*
1384 – 1387
Dynamic Materials through
Metal-Directed and Solvent-Driven
Self-Assembly of Cavitands
gation (SA) and metal coordination (MC),
allows precise control at each step of the
self-assembly cycle, leading to the formation of rodlike supramolecular architectures.
A dual-coded dynamic material was created by the bimodal self-assembly protocol sketched in the scheme. The combination of two orthogonal and reversible
interactions, namely solvophobic aggre-
O
EtO
O
O
OH
EtO
+
O
P
O
S
O2
2) KOH, Al2O3
CBr2F2, CH2Cl2
tBuOH, 5°C
O
Eight illustrious organic chemists in one
pot! A route from protected monosaccharides to novel C-glycosides and Clinked disaccharides is described which
involves tandem Horner–Wadsworth–
Angew. Chem. Int. Ed. 2003, 42, 1322 – 1328
R
1) NaH
THF, –78°C
Preparing C-Linked Disaccharides
O
R
O
O
O
G. D. McAllister, D. E. Paterson,
R. J. K. Taylor*
1387 – 1391
O
Emmons/conjugate addition (Michaeltype), followed by tandem halogenation/
Ramberg–BTcklund reaction using the
Meyers–Chan procedure (see scheme,
R = protected saccharide).
2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
A Simplified Ramberg–BTcklund
Approach to Novel C-Glycosides and
C-Linked Disaccharides
1433-7851/03/4212-1325 $ 20.00+.50/0
1325
Contents
The calculated structures of a supported
Rh6 cluster (depicted) demonstrate that
protons of surface OH groups of the oxide
support migrate onto the cluster. This
migration results in the oxidation of metal
atoms that are in close contact with the
support. The energy released by this
reverse hydrogen spillover is estimated to
be 120 kJ mol1 per OH group.
Supported Cluster Calculations
G. N. Vayssilov, B. C. Gates,
N. R'sch*
1391 – 1394
Oxidation of Supported Rhodium Clusters
by Support Hydroxy Groups
NMR Studies of Glycopeptides
S. Ilin, C. Bosques, C. Turner,
H. Schwalbe*
1394 – 1397
G-HMBC: An NMR Experiment for the
Conformational Analysis of the
o-Glycosidic Linkage in Glycopeptides
A more sensitive approach: A variation on
the heteronuclear multiple-bond correlation technique has been devised which
can determine the conformation around
the glycosidic bonds in oligosaccharides
and glycopeptides. The key section of the
studied glycopeptide 1 is shown, for which
Unsaturated Bicyclic Lactones
A. Kamitani, N. Chatani,*
S. Murai
1397 – 1399
Highly unsaturated g-lactones are formed
in good to high yields from 2-(propargyl)-
measurements of the torsion angles f
and y, derived from 3J(C,H) coupling
constants and cross-correlated relaxation
rates, compare favorably with those
determined by X-ray diffraction or molecular dynamic analysis.
allyl phosphates and carbon monoxide in
the presence of a palladium catalyst (see
scheme). The reaction proceeds efficiently
under mild reaction conditions (at 80 8C
under an ambient pressure of CO).
Palladium-Catalyzed Carbonylation of
2-(Propargyl)allyl Phosphates Leading
to Highly Unsaturated g-Lactones
2+
Pt-Capped C-Rich Molecular Rods
V. W.-W. Yam,* K. M.-C. Wong,
N. Zhu
1400 – 1403
Luminescent Platinum(ii) TerpyridylCapped Carbon-Rich Molecular Rods—An
Extension from Molecular- to NanometerScale Dimensions
1326
2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
N
N
N
Pt
C
C
Pt
N
n
N
N
1: n = 1, X = OTf –
2: n = 2, X = OTf –
3: n = 4, X = PF6–
1433-7851/03/4212-1326 $ 20.00+.50/0
(X)2
A change in shift! In contrast to the red
shift commonly found in organic polyynes
and other metal–alkynyl systems, a blue
shift in the transition energy was observed
in electronic absorption and emission
studies on a novel series of structurally
characterized dinuclear platinum(ii)–
terpyridyl complexes [{Pt(tBu3-tpy)}2(CC)n](X)2 (1–3; tBu3-tpy = 4,4’,4’’-tritert-butyl-2,2’:6’,2’’-terpyridine) upon
increasing the extent of p conjugation of
the alkynyl bridge.
Angew. Chem. Int. Ed. 2003, 42, No. 12
Angewandte
Chemie
ABC Triblock Copolymers
F. Liu, A. Eisenberg*
1404 – 1407
Synthesis of Poly(tert-butyl acrylate)-blockPolystyrene-block-Poly(4-vinylpyridine) by
Living Anionic Polymerization
anionic polymerization, and then used in
the initiation of the anionic polymerization of styrene (green). As the styryl anion
remained “alive” in the presence of the
poly(tert-butyl acrylate) block, the 4-vinylpyridine (red) polymerization could proceed after monomer addition.
Breathing new life into anionic polymerization: A novel ABC triblock, poly(tertbutyl acrylate)-block-polystyrene-blockpoly(4-vinylpyridine) (depicted), was synthesized by living anionic polymerization.
A functional macromonomer, poly(tertbutyl acrylate) (blue) with a styrene end
group (black) was first prepared by
Biaryl Coupling Reactions
N. E. Leadbeater,*
M. Marco
additive (see scheme). Products were
obtained in high yields with a wide range
of aryl bromide substrates.
No metal required: The first transitionmetal-free Suzuki-type coupling reaction
was carried out in water by using tetrabutylammonium bromide (TBAB) as an
1407 – 1409
Transition-Metal-Free Suzuki-Type
Coupling Reactions
Synthesis of Oxazoles
P.-Y. Coqueron, C. Didier,
M. A. Ciufolini*
with a-chloroglycinates. This approach
was used in the total synthesis of the
bisoxazole natural product, ()-muscoride A.
An efficient iterative synthesis of oxazoles
involves the cyclization of 2-alkynyl glycinates (see scheme) formed from the
reaction of 1-alkynyl aluminum reagents
F5C6
C6F5
F
Zr
SiMe3
F
F
+
Iterative Oxazole Assembly via
a-Chloroglycinates: Total Synthesis of
()-Muscoride A
Olefin Polymerization Catalysts
F
B–
1411 – 1414
F
M=Zr
SiMe3
+ B(C6F5)3
M
H
M=Ti
+ B(C6F5)3
– SiMe3
C6F5
+
B– C F
6 5
Ti
F
SiMe3
SiMe3
F
F
SiMe3
F
F
1
2
Stabilization by coordination: A long
sought after intermediate is stabilized by
complexation: B(C6F5)3 reacts at a bis(trimethylsilyl)acetylene titanium complex
with CSi bond cleavage and BC bond
Angew. Chem. Int. Ed. 2003, 42, 1322 – 1328
P. Arndt, W. Baumann, A. Spannenberg,
U. Rosenthal,* V. V. Burlakov,
V. B. Shur
1414 – 1418
formation to give the coordinatively stabilized (trimethylsilyl)alkynylboranate 1.
The reaction of the corresponding zirconium complex proceeds totally different
giving the agostic complex 2.
2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Reactions of Titanium and Zirconium
Derivatives of Bis(trimethylsilyl)acetylene
with Tris(pentafluorophenyl)borane: A
Titanium(iii) Complex of an Alkynylboranate
1433-7851/03/4212-1327 $ 20.00+.50/0
1327
Contents
High-Throughput Enzyme Assay
M. Konarzycka-Bessler,
U. T. Bornscheuer*
1418 – 1420
A High-Throughput-Screening Method for
Determining the Synthetic Activity of
Hydrolases
A glowing success in enzyme assay: The
first high-throughput format for the
determination of synthetic activity of
lipases and esterases in organic solvents
is described. Acetaldehyde released by
enzyme-catalyzed esterification between a
Communications labeled with
this symbol have been judged
by two referees as being “very
important papers”.
vinyl ester and an alcohol is derivatized
in situ with a hydrazine 1 to give a highly
fluorescent product 2. Thus, active and
stable enzymes can be easily identified in
a microtiter plate format.
The publication of
Communications labeled with
this symbol has been
accelerated because of their
topical or highly competitive
nature.
Supporting information for
articles labeled with this symbol
can be found at
www.angewandte.org or
www.interscience.wiley.com.
Service
Keywords
1422
Authors
1423
Events
1426
Vacancies
1339
Preview
1425
Corrigendum
*
In the Communication by J.-M. Zen et al. published in Angew. Chem. Int. Ed. 2003, 5, 577–579, the reduction of [Ru(bpy)3]3+ to
[Ru(bpy)3]2+ in Scheme 1 (as well as in the graphical abstract) should be accompanied by an oxidation of RSCH3 with H2O2 to
RSOCH3. There were also some ambiguities as to which isomer was used. The footnote to Table 1 should read: [a] +: presence,
: absence, [RC6H4SCH3 : R = H, p-COCH3, p-OCH3] = 17 mm of each separately, Entries 1–8 tested with PhSCH3.
1328
2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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Angew. Chem. Int. Ed. 2003, 42, No. 12
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