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P. Fita Dr. N. Urbańska Dr. C. Radzewicz Prof. Dr. J. Waluk Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(19):4851-4856
Reaction rates from polarized spectroscopy : A new method based on ultrafast pump–probe polarization spectroscopy enables the measurement of the ground‐ and excited‐state reaction rates for self‐exchange processes. The technique was used to study double hydrogen transfer in porphycene and its derivatives (see figure).
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Anne Brennführer Helfried Neumann Dr. Matthias Beller Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(23):4114-4133
A CO group richer : (Hetero)arenes are vital intermediates in the manufacture of agrochemicals, dyes, pharmaceuticals, and other industrial products. In the past decades transition‐metal‐catalyzed coupling reactions of aryl halides with all types of nucleophiles have been developed. This Review summarizes recent work in the area of palladium‐catalyzed carbonylation reactions of aryl halides and related compounds (see scheme).
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Lutz F. Tietze Prof. Dr. Tom Kinzel Dr. Thomas Wolfram Dipl.‐Chem. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(25):6199-6210
To methyl or to alkyl? High induced facial selectivities and excellent yields are obtained in the allylation of aliphatic methyl ketones by using a structurally simple phenylbenzyl auxiliary to give the corresponding homoallylic ethers (see scheme). The transferred auxiliary has a very good protecting quality and can easily be removed.
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Suwei Dong Ernest Hamel Dr. Ruoli Bai Dr. David G. Covell Dr. John A. Beutler Dr. John A. Porco Jr. Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(8):1494-1497
A bicycle built for tubulin : The total synthesis of (+)‐chamaecypanone C has been achieved by using a tandem retro‐Diels–Alder/Diels–Alder cascade reaction (see scheme). Initial biological studies demonstrate that (+)‐chamaecypanone C is an inhibitor of tubulin assembly and binds at the colchicine site.
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Xue‐Yi Chen Charles Barnes Dr. Jerry R. Dias Prof. T. C. Sandreczki Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(9):2041-2044
Triethylamine hydroiodide crystals were formed during Sonogashira reactions; after complete reaction the solution retains a characteristic light color (see picture). Very sluggish Sonogashira reactions of electron‐enriched aryl diiodides have been carried out in high yield in an oxygen‐free, two‐chamber reaction system. The formation of triethylamine hydroiodide crystals was monitored to determine the completion of reaction.
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Gérard Cahiez Dr. Laura Foulgoc Alban Moyeux 《Angewandte Chemie (International ed. in English)》2009,48(16):2969-2972
Aryl–alkyl cross‐coupling products are obtained by the iron‐catalyzed oxidative heterocoupling of organozinc reagents under mild conditions. This novel reaction pathway is versatile, allowing for the use of primary and secondary aliphatic diorganozinc reagents as coupling partners as well as tolerating functionalized aryl‐ and alkylzinc reagents.
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Martin B. Duriska Dr. Suzanne M. Neville Dr. Boujemaa Moubaraki Dr. John D. Cashion Assoc. Prof Gregory J. Halder Dr. Karena W. Chapman Dr. Chérif Balde Jean‐François Létard Dr. Keith S. Murray Prof. Cameron J. Kepert Prof. Stuart R. Batten Assoc. Prof. 《Angewandte Chemie (International ed. in English)》2009,48(14):2428-2428
Continuous switching between high‐spin and low‐spin magnetic states can be accomplished by irradiation with red and green laser light, respectively. In their Communication on page 2549 ff., S. R. Batten and co‐workers report a metallo‐supramolecule that undergoes spin crossover (SCO) switching induced by temperature change or light irradiation. The SCO behavior is also dependent on the presence and nature of intercalated solvent molecules within the porous crystal structure.
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Jun Shi Hiroki Shigehisa Dr. Carlos A. Guerrero Ryan A. Shenvi Chuang‐Chuang Li Dr. Phil S. Baran Prof. 《Angewandte Chemie (International ed. in English)》2009,48(24):4328-4331
One stereocenter makes all the difference : The synthesis and biological evaluation of 17‐epi‐cortistatin A is reported from a common intermediate used to procure natural cortistatin A. The synthesis features a unique stereocontrolled Raney‐Ni reduction process that can be employed to reliably produce both α‐ and β‐configured D‐ring aryl steroids. Biological evaluations of these “cortalogs” are reported for the first time.
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Naiwei Wang Dr. Tsutomu Matsumoto Masaharu Ueno Dr. Hiroyuki Miyamura Shū Kobayashi Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(26):4744-4746
Golden capillaries : A gold‐immobilized capillary column reactor allows oxidation of alcohols to carbonyl compounds using molecular oxygen. These capillary columns (see picture) can be used for at least four days without loss of activity.
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Hoi‐Yan Shiu Tak‐Chung Chan Dr. Chi‐Ming Ho Dr. Yungen Liu Dr. Man‐Kin Wong Dr. Chi‐Ming Che Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(15):3839-3850
Enriched cleavage : An efficient chemoselective cysteine modification of unprotected peptides and proteins has been developed by using electron‐deficient alkynes in aqueous media. Interestingly, terminal alkynone‐modified peptides could be converted back into the unmodified peptides by cleavage by adding thiols under mild conditions (see scheme).
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Peter Jutzi Prof. Dr. Kinga Leszczyńska Dr. Beate Neumann Wolfgang W. Schoeller Prof. Dr. Hans‐Georg Stammler Dr. 《Angewandte Chemie (International ed. in English)》2009,48(14):2596-2599
Si takes a rest : A bulky σ‐bound terphenyl substituent and a π‐bound Cp* ligand enable the isolation and full characterization of the first aryl‐substituted, monomeric silicon(II) compound 1 , which can be regarded as the “resting state” of a true silylene containing a σ‐bound Cp* group. The conformation of the aryl group prevents aryl–Si π back‐bonding.
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Anthony J. Zucchero Rebecca A. Shiels Psaras L. McGrier M. Alicia To Christopher W. Jones Prof. Uwe H. F. Bunz Prof. 《化学:亚洲杂志》2009,4(2):262-269
Silica scaffolding : By employing functionalized mesoporous SBA‐15 silica, novel fluorescent cruciform‐silica hybrid materials are generated which preserve the desirable solution properties of cruciforms in the solid state for potential use in sensory schemes.
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Thomas M. Gøgsig Anders T. Lindhardt Dr. Mouloud Dekhane Dr. Julie Grouleff Troels Skrydstrup Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(24):5950-5955
Easy and direct : Regioselective Mizoroki–Heck‐coupling reactions using heteroaromatic tosylates as electrophiles were achieved, thus providing direct and easy access to highly functionalized α‐heteroarylvinyl amides and ethers.
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Jing Tan Xianxiu Xu Dr. Lingjuan Zhang Yifei Li Qun Liu Prof. 《Angewandte Chemie (International ed. in English)》2009,48(16):2868-2872
Up to four adjacent stereocenters can be formed stereoselectively in the construction of a pyrrolizidine unit through a novel organocatalytic reaction that involves treatment of various dienones with ethyl isocyanoacetate (see scheme; DBU=1,8‐diazabicyclo[5.4.0]undec‐7‐ene). Mechanisms for this atom‐economic, one‐pot synthesis have been proposed.